Equation form expr-002bf3eb1573e012
Read as: k plus one
Means: k plus one
Incompleteness
Read as: k plus one
Means: k plus one
Read as: A subscript zero function of x and y is the formula y equals the object language constant zero
Means: A subscript zero function of x and y is the formula y equals the object language constant zero
Read as: Q proves that not A of the numeral for n
Means: Q proves that not A of the numeral for n
Read as: A subscript f of z and y is the conjunction of A subscript g of y, z, and the object language constant zero, with the following universal statement: for every w, if w is less than y then not A subscript g of w, z, and the object language constant zero
Means: A subscript f of z and y is the conjunction of A subscript g of y, z, and the object language constant zero, with the following universal statement: for every w, if w is less than y then not A subscript g of w, z, and the object language constant zero
Read as: y subscript n
Means: y subscript n
Read as: the sum of the successor of b and a equals the object language constant zero
Means: the sum of the successor of b and a equals the object language constant zero
Read as: h of the tuple x and y equals beta of h hat of the tuple x and y, and y
Means: h of the tuple x and y equals beta of h hat of the tuple x and y, and y
Read as: the sum of the successor of z and t subscript one equals t subscript two
Means: the sum of the successor of z and t subscript one equals t subscript two
Read as: Provability in Q holds of y by definition if and only if y is a sentence code and there exists x which codes a derivation in Q of the formula with code y
Means: Provability in Q holds of y by definition if and only if y is a sentence code and there exists x which codes a derivation in Q of the formula with code y
Read as: A is the formula there exists x such that B of x
Means: A is the formula there exists x such that B of x
Read as: the successor of the sum of the successor of b and c equals the object language constant zero
Means: the successor of the sum of the successor of b and c equals the object language constant zero
Read as: the multiplication function applied to x subscript zero and x subscript one equals x subscript zero times x subscript one
Means: the multiplication function applied to x subscript zero and x subscript one equals x subscript zero times x subscript one
Read as: s
Means: s
Read as: Q proves that A subscript h of the numeral for n and the numeral for m
Means: Q proves that A subscript h of the numeral for n and the numeral for m
Read as: the successor of the sum of the successor of z and the numeral for n minus m minus one equals the object language constant zero
Means: the successor of the sum of the successor of z and the numeral for n minus m minus one equals the object language constant zero
Read as: n does not equal k
Means: n does not equal k
Read as: a subscript n
Means: a subscript n
Read as: Q proves that for every w, if w is less than the numeral for m then not A subscript g of w, the numeral for n, and the object language constant zero
Means: Q proves that for every w, if w is less than the numeral for m then not A subscript g of w, the numeral for n, and the object language constant zero
Read as: The value of the term t subscript one plus t subscript two in the standard model N equals the value of t subscript one in N plus the value of t subscript two in N. This equals n subscript one plus n subscript two
Means: The value of the term t subscript one plus t subscript two in the standard model N equals the value of t subscript one in N plus the value of t subscript two in N. This equals n subscript one plus n subscript two
Read as: x subscript n
Means: x subscript n
Read as: the successor function
Means: the successor function
Read as: A subscript equality applied to the numerals for n and m, and the numeral for one
Means: A subscript equality applied to the numerals for n and m, and the numeral for one
Read as: n equals m
Means: n equals m
Read as: Q proves A subscript f applied to the numerals for n subscript zero through n subscript k, and the numeral for m, if and only if m equals f of n subscript zero through n subscript k
Means: Q proves A subscript f applied to the numerals for n subscript zero through n subscript k, and the numeral for m, if and only if m equals f of n subscript zero through n subscript k
Read as: p divides one plus the product of i plus one and m
Means: p divides one plus the product of i plus one and m
Read as: h hat of the tuple x and y
Means: h hat of the tuple x and y
Read as: g subscript zero
Means: g subscript zero
Read as: n does not equal m
Means: n does not equal m
Read as: R of n subscript zero through n subscript k, and s
Means: R of n subscript zero through n subscript k, and s
Read as: j equals the maximum of n, y subscript zero plus one, and so on through y subscript n plus one. m equals the least common multiple of the integers one through j
Means: j equals the maximum of n, y subscript zero plus one, and so on through y subscript n plus one. m equals the least common multiple of the integers one through j
Read as: the numeral for k
Means: the numeral for k
Read as: a is less than the numeral for one
Means: a is less than the numeral for one
Read as: h of n equals m
Means: h of n equals m
Read as: x is less than the numeral for k plus one
Means: x is less than the numeral for k plus one
Read as: for every x less than t, not A of x
Means: for every x less than t, not A of x
Read as: A subscript g of x and y
Means: A subscript g of x and y
Read as: m is less than or equal to n
Means: m is less than or equal to n
Read as: Base case: h of the tuple x and zero equals f of the tuple x. Recursion step: h of the tuple x and y plus one equals g of the tuple x, y, and h of the tuple x and y
Means: Base case: h of the tuple x and zero equals f of the tuple x. Recursion step: h of the tuple x and y plus one equals g of the tuple x, y, and h of the tuple x and y
Read as: A subscript Add of x subscript zero, x subscript one, and y is the formula y equals the sum of x subscript zero and x subscript one
Means: A subscript Add of x subscript zero, x subscript one, and y is the formula y equals the sum of x subscript zero and x subscript one
Read as: y subscript i is less than j; j is less than or equal to m; and m is less than x subscript i
Means: y subscript i is less than j; j is less than or equal to m; and m is less than x subscript i
Read as: for all x and y, if their successors are equal, then x equals y
Means: for all x and y, if their successors are equal, then x equals y
Read as: Q proves that for every y, if A subscript f holds of the numeral for n and y, then y equals the numeral for m
Means: Q proves that for every y, if A subscript f holds of the numeral for n and y, then y equals the numeral for m
Read as: the successor of z does not equal the object language constant zero
Means: the successor of z does not equal the object language constant zero
Read as: f of y subscript zero through y subscript k minus one
Means: f of y subscript zero through y subscript k minus one
Read as: the numeral for m plus one
Means: the numeral for m plus one
Read as: A subscript g of x, z, and y
Means: A subscript g of x, z, and y
Read as: the absolute value of i minus k
Means: the absolute value of i minus k
Read as: there exists y such that the sum of the successor of y and a equals the object language constant zero
Means: there exists y such that the sum of the successor of y and a equals the object language constant zero
Read as: omega
Means: omega
Read as: Q proves that the sum of the successor of the numeral for k and t subscript one equals t subscript two
Means: Q proves that the sum of the successor of the numeral for k and t subscript one equals t subscript two
Read as: the standard model N under assignment s satisfies A of x
Means: the standard model N under assignment s satisfies A of x
Read as: n equals zero
Means: n equals zero
Read as: Q proves that the numeral for l equals the numeral for m
Means: Q proves that the numeral for l equals the numeral for m
Read as: the successor function applied to x equals x plus one
Means: the successor function applied to x equals x plus one
Read as: Q proves that for every x, if x is less than the numeral for n plus one, then x equals one of the numerals from zero through n
Means: Q proves that for every x, if x is less than the numeral for n plus one, then x equals one of the numerals from zero through n
Read as: p
Means: p
Read as: c is less than the object language constant zero
Means: c is less than the object language constant zero
Read as: A subscript Add applied to x subscript zero, x subscript one, and y
Means: A subscript Add applied to x subscript zero, x subscript one, and y
Read as: the value of t subscript two in the standard model N is less than or equal to the value of t subscript one in the standard model N
Means: the value of t subscript two in the standard model N is less than or equal to the value of t subscript one in the standard model N
Read as: x subscript k
Means: x subscript k
Read as: the numeral for two
Means: the numeral for two
Read as: Q proves that the sum of the numeral for n and the successor of the numeral for m equals the successor of the numeral for n plus m
Means: Q proves that the sum of the numeral for n and the successor of the numeral for m equals the successor of the numeral for n plus m
Read as: Q proves that A subscript equality applied to the numerals for n and m, and the numeral for zero
Means: Q proves that A subscript equality applied to the numerals for n and m, and the numeral for zero
Read as: the successor of b is less than the numeral for n plus two
Means: the successor of b is less than the numeral for n plus two
Read as: d
Means: d
Read as: the sum of the successor of c and the successor of the numeral for m equals the successor of b
Means: the sum of the successor of c and the successor of the numeral for m equals the successor of b
Read as: Q does not prove that there exists y such that A of y
Means: Q does not prove that there exists y such that A of y
Read as: Q proves that t subscript two equals the numeral for n
Means: Q proves that t subscript two equals the numeral for n
Read as: there exists x less than t such that A of x
Means: there exists x less than t such that A of x
Read as: rem of x and y, the remainder when y is divided by x
Means: rem of x and y, the remainder when y is divided by x
Read as: assignment s sends x to n
Means: assignment s sends x to n
Read as: n
Means: n
Read as: Q proves that the numeral for l does not equal the numeral for m
Means: Q proves that the numeral for l does not equal the numeral for m
Read as: there exists x less than t such that not A of x
Means: there exists x less than t such that not A of x
Read as: f of g of n equals m
Means: f of g of n equals m
Read as: m equals f of n subscript zero through n subscript k
Means: m equals f of n subscript zero through n subscript k
Read as: z subscript zero
Means: z subscript zero
Read as: Q proves that the finite disjunction of A applied to each numeral from zero through k minus one
Means: Q proves that the finite disjunction of A applied to each numeral from zero through k minus one
Read as: n plus one
Means: n plus one
Read as: a is congruent to b modulo c
Means: a is congruent to b modulo c
Read as: the Goedel number of the formula there exists y such that B subscript T holds of the numeral for e, the numeral for n, and y
Means: the Goedel number of the formula there exists y such that B subscript T holds of the numeral for e, the numeral for n, and y
Read as: B subscript T
Means: B subscript T
Read as: Q proves that A subscript f of the numeral for n and the numeral for m
Means: Q proves that A subscript f of the numeral for n and the numeral for m
Read as: the numeral for m
Means: the numeral for m
Read as: the value of the object language constant zero in the standard model N equals zero
Means: the value of the object language constant zero in the standard model N equals zero
Read as: the disjunction of A and B
Means: the disjunction of A and B
Read as: the quantity one plus the product of i plus one and m, minus the quantity one plus the product of k plus one and m, equals the product of i minus k and m
Means: the quantity one plus the product of i plus one and m, minus the quantity one plus the product of k plus one and m, equals the product of i minus k and m
Read as: a equals the successor of b
Means: a equals the successor of b
Read as: a subscript zero
Means: a subscript zero
Read as: A subscript successor function of x and y is the formula y equals the successor of x
Means: A subscript successor function of x and y is the formula y equals the successor of x
Read as: the successor of b is less than the successor of the numeral for n plus one
Means: the successor of b is less than the successor of the numeral for n plus one
Read as: f
Means: f
Read as: the value of t subscript one in the standard model N is less than the value of t subscript two in the standard model N
Means: the value of t subscript one in the standard model N is less than the value of t subscript two in the standard model N
Read as: k is a natural number
Means: k is a natural number
Read as: y subscript i
Means: y subscript i
Read as: f of n subscript zero through n subscript k equals m
Means: f of n subscript zero through n subscript k equals m
Read as: Q proves that the numeral for k equals the sum of the numeral for n and the numeral for m
Means: Q proves that the numeral for k equals the sum of the numeral for n and the numeral for m
Read as: h hat
Means: h hat
Read as: z equals f of y
Means: z equals f of y
Read as: Q proves that the sum of t subscript one and t subscript two equals the sum of the numeral for n subscript one and t subscript two
Means: Q proves that the sum of t subscript one and t subscript two equals the sum of the numeral for n subscript one and t subscript two
Read as: A subscript f of y and z
Means: A subscript f of y and z
Read as: k equals g of n
Means: k equals g of n
Read as: there exists u such that the sum of the successor of u and the successor of b equals the numeral for m plus one
Means: there exists u such that the sum of the successor of u and the successor of b equals the numeral for m plus one
Read as: Q proves that it is not the case that t subscript one is less than t subscript two
Means: Q proves that it is not the case that t subscript one is less than t subscript two
Read as: x
Means: x
Read as: f of z equals the least x such that g of x and z equals zero
Means: f of z equals the least x such that g of x and z equals zero
Read as: the characteristic function of R applied to x subscript zero through x subscript k
Means: the characteristic function of R applied to x subscript zero through x subscript k
Read as: c
Means: c
Read as: A subscript characteristic function of equality, applied to x subscript zero, x subscript one, and y, is the following disjunction. Either x subscript zero equals x subscript one and y equals the numeral for one; or x subscript zero does not equal x subscript one and y equals the numeral for zero
Means: A subscript characteristic function of equality, applied to x subscript zero, x subscript one, and y, is the following disjunction. Either x subscript zero equals x subscript one and y equals the numeral for one; or x subscript zero does not equal x subscript one and y equals the numeral for zero
Read as: not A subscript characteristic function of R, applied to the numerals for n subscript zero through n subscript k, and the numeral for one
Means: not A subscript characteristic function of R, applied to the numerals for n subscript zero through n subscript k, and the numeral for one
Read as: the negation of the bounded existential formula with variable x, bound t, and matrix A of x
Means: the negation of the bounded existential formula with variable x, bound t, and matrix A of x
Read as: f of the tuple x
Means: f of the tuple x
Read as: x subscript zero
Means: x subscript zero
Read as: the object language constant zero is less than a
Means: the object language constant zero is less than a
Read as: d is the Goedel number of a derivation in Q of the formula with Goedel number y
Means: d is the Goedel number of a derivation in Q of the formula with Goedel number y
Read as: if the numeral for n does not equal the numeral for k, then their successors do not equal each other
Means: if the numeral for n does not equal the numeral for k, then their successors do not equal each other
Read as: h of x subscript zero through x subscript l minus one equals f applied to the outputs of g subscript zero through g subscript k minus one, each evaluated on that same input tuple x subscript zero through x subscript l minus one
Means: h of x subscript zero through x subscript l minus one equals f applied to the outputs of g subscript zero through g subscript k minus one, each evaluated on that same input tuple x subscript zero through x subscript l minus one
Read as: b equals one of the numerals from zero through n
Means: b equals one of the numerals from zero through n
Read as: the object language multiplication symbol
Means: the object language multiplication symbol
Read as: for all x and y, the sum of the successor of x and y equals the successor of the sum of x and y
Means: for all x and y, the sum of the successor of x and y equals the successor of the sum of x and y
Read as: Q proves that for every z, if A subscript h holds of the numeral for n and z, then z equals the numeral for m
Means: Q proves that for every z, if A subscript h holds of the numeral for n and z, then z equals the numeral for m
Read as: the quantity i minus k, times m
Means: the quantity i minus k, times m
Read as: g subscript i of x subscript zero through x subscript l minus one
Means: g subscript i of x subscript zero through x subscript l minus one
Read as: h of x equals f of g of x
Means: h of x equals f of g of x
Read as: one plus two times d subscript one
Means: one plus two times d subscript one
Read as: Q proves that the object language product of the numeral for n and the numeral for m equals the numeral for n times m
Means: Q proves that the object language product of the numeral for n and the numeral for m equals the numeral for n times m
Read as: g subscript i
Means: g subscript i
Read as: g of x and z
Means: g of x and z
Read as: for every w, if w is less than b then not A subscript g of w, the numeral for n, and the object language constant zero
Means: for every w, if w is less than b then not A subscript g of w, the numeral for n, and the object language constant zero
Read as: the sum of the successor of c and the successor of b equals the successor of the numeral for m
Means: the sum of the successor of c and the successor of b equals the successor of the numeral for m
Read as: equality
Means: equality
Read as: x is less than the numeral for zero
Means: x is less than the numeral for zero
Read as: the provability relation for Q
Means: the provability relation for Q
Read as: Q proves that the sum of t subscript one and t subscript two equals the numeral for n subscript one plus n subscript two
Means: Q proves that the sum of t subscript one and t subscript two equals the numeral for n subscript one plus n subscript two
Read as: Q proves that not B subscript T applied to the numerals for e, n, and s
Means: Q proves that not B subscript T applied to the numerals for e, n, and s
Read as: the entry beta of d and zero equals f of the tuple x
Means: the entry beta of d and zero equals f of the tuple x
Read as: beta of d and i
Means: beta of d and i
Read as: Q proves that A subscript f applied to the numerals for n subscript zero through n subscript k, and the numeral for m
Means: Q proves that A subscript f applied to the numerals for n subscript zero through n subscript k, and the numeral for m
Read as: there exists x such that both x is less than t and A of x
Means: there exists x such that both x is less than t and A of x
Read as: R of x subscript zero through x subscript k
Means: R of x subscript zero through x subscript k
Read as: for all x and y, the sum of x and y equals the sum of y and x
Means: for all x and y, the sum of x and y equals the sum of y and x
Read as: Q
Means: Q
Read as: A subscript h of x and z
Means: A subscript h of x and z
Read as: the bounded universal formula with variable x, bound t, and matrix A of x
Means: the bounded universal formula with variable x, bound t, and matrix A of x
Read as: x is less than y if and only if there exists z such that the sum of the successor of z and x equals y
Means: x is less than y if and only if there exists z such that the sum of the successor of z and x equals y
Read as: the successor of the object language constant zero
Means: the successor of the object language constant zero
Read as: b
Means: b
Read as: e
Means: e
Read as: Step one. Q proves that the sum of the successor of a and the object language constant zero equals the successor of a, by axiom Q subscript four. Step two. Q proves that the sum of a and that constant zero equals a, by axiom Q subscript four. Step three. Q proves that the successor of the sum of a and that constant zero equals the successor of a, by step two of the successor and fixed numeral addition derivation. Therefore Q proves that the sum of the successor of a and that constant zero equals the successor of the sum of a and that constant zero, by step one of the successor and fixed numeral addition derivation and step three of the successor and fixed numeral addition derivation
Means: Step one. Q proves that the sum of the successor of a and the object language constant zero equals the successor of a, by axiom Q subscript four. Step two. Q proves that the sum of a and that constant zero equals a, by axiom Q subscript four. Step three. Q proves that the successor of the sum of a and that constant zero equals the successor of a, by step two of the successor and fixed numeral addition derivation. Therefore Q proves that the sum of the successor of a and that constant zero equals the successor of the sum of a and that constant zero, by step one of the successor and fixed numeral addition derivation and step three of the successor and fixed numeral addition derivation
Read as: h hat of the tuple x and y equals the least d satisfying both of the following conditions. Beta of d and zero equals f of the tuple x. And for every i less than y, beta of d and i plus one equals g of the tuple x, i, and beta of d and i
Means: h hat of the tuple x and y equals the least d satisfying both of the following conditions. Beta of d and zero equals f of the tuple x. And for every i less than y, beta of d and i plus one equals g of the tuple x, i, and beta of d and i
Read as: the entry beta of d and i plus one equals g of the tuple x, i, and the entry beta of d and i
Means: the entry beta of d and i plus one equals g of the tuple x, i, and the entry beta of d and i
Read as: A subscript f applied to the numerals for n subscript zero through n subscript k, and the entry at position one in the prime power sequence coded by s
Means: A subscript f applied to the numerals for n subscript zero through n subscript k, and the entry at position one in the prime power sequence coded by s
Read as: j is greater than or equal to n
Means: j is greater than or equal to n
Read as: the characteristic function of R applied to n subscript zero through n subscript k equals one
Means: the characteristic function of R applied to n subscript zero through n subscript k equals one
Read as: the second successor of zero does not equal the third successor of zero
Means: the second successor of zero does not equal the third successor of zero
Read as: the existential formula with bound variable x and matrix A of x
Means: the existential formula with bound variable x and matrix A of x
Read as: m equals zero
Means: m equals zero
Read as: f of z
Means: f of z
Read as: the sum of the successor of b and the successor of c equals the object language constant zero
Means: the sum of the successor of b and the successor of c equals the object language constant zero
Read as: y is the Goedel number of a sentence provable in Q
Means: y is the Goedel number of a sentence provable in Q
Read as: the sum of the successor of a and the object language constant zero equals the successor of the sum of a and the object language constant zero
Means: the sum of the successor of a and the object language constant zero equals the successor of the sum of a and the object language constant zero
Read as: not A is the formula not not B
Means: not A is the formula not not B
Read as: the negation of the disjunction of A and B
Means: the negation of the disjunction of A and B
Read as: A of n subscript zero through n subscript k, and m, equals the Goedel number of A subscript f applied to the numerals for n subscript zero through n subscript k, and the numeral for m
Means: A of n subscript zero through n subscript k, and m, equals the Goedel number of A subscript f applied to the numerals for n subscript zero through n subscript k, and the numeral for m
Read as: g of w and z does not equal zero
Means: g of w and z does not equal zero
Read as: The simultaneous congruences are: z is congruent to y subscript zero modulo x subscript zero; z is congruent to y subscript one modulo x subscript one; and so on, through z congruent to y subscript n modulo x subscript n
Means: The simultaneous congruences are: z is congruent to y subscript zero modulo x subscript zero; z is congruent to y subscript one modulo x subscript one; and so on, through z congruent to y subscript n modulo x subscript n
Read as: the sum of the numeral for n and the numeral for m
Means: the sum of the numeral for n and the numeral for m
Read as: Q proves that the sum of the numeral for n and the object language constant zero equals the numeral for n
Means: Q proves that the sum of the numeral for n and the object language constant zero equals the numeral for n
Read as: Q subscript one
Means: Q subscript one
Read as: A subscript f of the numeral for n and b
Means: A subscript f of the numeral for n and b
Read as: A of n subscript zero through n subscript k, and m, equals the result of these nested calls to the substitution coding function Subst. Start with the Goedel number of A subscript f. Substitute the numeral code num of n subscript zero for the variable code of x subscript zero. Continue in order through substitution of num of n subscript k for the variable code of x subscript k. Finally substitute num of m for the variable code of y. Each call takes the current formula code, the replacement numeral code, and the selected variable code, in that order
Means: A of n subscript zero through n subscript k, and m, equals the result of these nested calls to the substitution coding function Subst. Start with the Goedel number of A subscript f. Substitute the numeral code num of n subscript zero for the variable code of x subscript zero. Continue in order through substitution of num of n subscript k for the variable code of x subscript k. Finally substitute num of m for the variable code of y. Each call takes the current formula code, the replacement numeral code, and the selected variable code, in that order
Read as: Q
Means: Q
Read as: Q proves that the numeral for n equals the numeral for m
Means: Q proves that the numeral for n equals the numeral for m
Read as: the n argument projection function with index i
Means: the n argument projection function with index i
Read as: a subscript zero through a subscript n
Means: a subscript zero through a subscript n
Read as: x subscript i
Means: x subscript i
Read as: Q proves that the successor of t subscript one equals the numeral for n subscript one plus one
Means: Q proves that the successor of t subscript one equals the numeral for n subscript one plus one
Read as: the numeral for m
Means: the numeral for m
Read as: the sum of the numeral for n and the numeral for m equals y
Means: the sum of the numeral for n and the numeral for m equals y
Read as: the numeral for zero is the object language constant zero
Means: the numeral for zero is the object language constant zero
Read as: f of n subscript zero through n subscript k equals the entry at position one in the prime power sequence whose code is the least s such that R holds of n subscript zero through n subscript k, and s
Means: f of n subscript zero through n subscript k equals the entry at position one in the prime power sequence whose code is the least s such that R holds of n subscript zero through n subscript k, and s
Read as: the numeral for n equals the numeral for n
Means: the numeral for n equals the numeral for n
Read as: truth
Means: truth
Read as: the sum of the successor of b and the object language constant zero equals the sum of a and the object language constant zero
Means: the sum of the successor of b and the object language constant zero equals the sum of a and the object language constant zero
Read as: x subscript zero through x subscript n
Means: x subscript zero through x subscript n
Read as: If both A holds of the object language constant zero, and for every x, A of x implies A of the successor of x, then A holds of every x
Means: If both A holds of the object language constant zero, and for every x, A of x implies A of the successor of x, then A holds of every x
Read as: Q proves that the numeral for n does not equal the numeral for k
Means: Q proves that the numeral for n does not equal the numeral for k
Read as: A subscript g
Means: A subscript g
Read as: Q subscript five
Means: Q subscript five
Read as: i minus k
Means: i minus k
Read as: for every y, A subscript f holds of the numerals for n subscript zero through n subscript k, and y, if and only if y equals the numeral for m
Means: for every y, A subscript f holds of the numerals for n subscript zero through n subscript k, and y, if and only if y equals the numeral for m
Read as: the characteristic function of equality applied to n and m equals one
Means: the characteristic function of equality applied to n and m equals one
Read as: the characteristic function of R applied to n subscript zero through n subscript k equals zero
Means: the characteristic function of R applied to n subscript zero through n subscript k equals zero
Read as: y equals the successor of x
Means: y equals the successor of x
Read as: a equals the object language constant zero
Means: a equals the object language constant zero
Read as: z
Means: z
Read as: either a equals the object language constant zero, or there exists y such that a is the successor of y
Means: either a equals the object language constant zero, or there exists y such that a is the successor of y
Read as: n is a natural number
Means: n is a natural number
Read as: the standard model N
Means: the standard model N
Read as: f of x subscript zero through x subscript k minus one
Means: f of x subscript zero through x subscript k minus one
Read as: the successor of c
Means: the successor of c
Read as: t subscript two
Means: t subscript two
Read as: m equals f of n
Means: m equals f of n
Read as: the zero function
Means: the zero function
Read as: zero
Means: zero
Read as: A is the formula t subscript one equals t subscript two
Means: A is the formula t subscript one equals t subscript two
Read as: y equals x subscript i
Means: y equals x subscript i
Read as: the successor of the sum of the successor of c and b equals the successor of the numeral for n plus one
Means: the successor of the sum of the successor of c and b equals the successor of the numeral for n plus one
Read as: the n argument projection function with index i, applied to x subscript zero through x subscript n minus one, equals x subscript i
Means: the n argument projection function with index i, applied to x subscript zero through x subscript n minus one, equals x subscript i
Read as: A subscript h
Means: A subscript h
Read as: m
Means: m
Read as: the sum of the successor of b and a equals the successor of the object language constant zero
Means: the sum of the successor of b and a equals the successor of the object language constant zero
Read as: A subscript equality applied to the numerals for n and m, and y
Means: A subscript equality applied to the numerals for n and m, and y
Read as: zero does not equal the successor of the numeral for k
Means: zero does not equal the successor of the numeral for k
Read as: A subscript f, and A subscript g subscript zero through A subscript g subscript k minus one
Means: A subscript f, and A subscript g subscript zero through A subscript g subscript k minus one
Read as: Q proves that t subscript one is less than t subscript two
Means: Q proves that t subscript one is less than t subscript two
Read as: the value of t subscript one in the standard model N equals n subscript one
Means: the value of t subscript one in the standard model N equals n subscript one
Read as: the addition function applied to x subscript zero and x subscript one equals the sum of x subscript zero and x subscript one
Means: the addition function applied to x subscript zero and x subscript one equals the sum of x subscript zero and x subscript one
Read as: A subscript R applied to the numerals for n subscript zero through n subscript k
Means: A subscript R applied to the numerals for n subscript zero through n subscript k
Read as: Q proves that for every y, if A subscript Add holds of the numeral for n, the numeral for m, and y, then y equals the numeral for k
Means: Q proves that for every y, if A subscript Add holds of the numeral for n, the numeral for m, and y, then y equals the numeral for k
Read as: n plus m
Means: n plus m
Read as: Q proves that A
Means: Q proves that A
Read as: the sequence a subscript zero through a subscript n
Means: the sequence a subscript zero through a subscript n
Read as: Q proves that for every y, if A subscript h holds of the numeral for n and y, then y equals the numeral for m
Means: Q proves that for every y, if A subscript h holds of the numeral for n and y, then y equals the numeral for m
Read as: one
Means: one
Read as: z equals f of g of x
Means: z equals f of g of x
Read as: the successor of the numeral for n plus m
Means: the successor of the numeral for n plus m
Read as: one plus the product of n plus one and d subscript one
Means: one plus the product of n plus one and d subscript one
Read as: a subscript i
Means: a subscript i
Read as: A subscript characteristic function of R, applied to x subscript zero through x subscript k, and the numeral for one
Means: A subscript characteristic function of R, applied to x subscript zero through x subscript k, and the numeral for one
Read as: g of x and z equals zero
Means: g of x and z equals zero
Read as: there does not exist y such that the sum of the successor of y and a equals the object language constant zero
Means: there does not exist y such that the sum of the successor of y and a equals the object language constant zero
Read as: the successor of the numeral for m
Means: the successor of the numeral for m
Read as: y equals the object language constant zero
Means: y equals the object language constant zero
Read as: Q proves that t equals the numeral for n
Means: Q proves that t equals the numeral for n
Read as: not A subscript g of b, the numeral for n, and the object language constant zero
Means: not A subscript g of b, the numeral for n, and the object language constant zero
Read as: the numeral for n plus one
Means: the numeral for n plus one
Read as: the numeral for n does not equal the numeral for m
Means: the numeral for n does not equal the numeral for m
Read as: A subscript f applied to y subscript zero through y subscript k minus one, and z
Means: A subscript f applied to y subscript zero through y subscript k minus one, and z
Read as: the successor of the numeral for k
Means: the successor of the numeral for k
Read as: Assume Q proves: for every y, either y is less than the numeral for m, or the numeral for m is less than y, or y equals the numeral for m. We want to show that Q proves: for every y, either y is less than the numeral for m plus one, or that numeral is less than y, or y equals that numeral
Means: Assume Q proves: for every y, either y is less than the numeral for m, or the numeral for m is less than y, or y equals the numeral for m. We want to show that Q proves: for every y, either y is less than the numeral for m plus one, or that numeral is less than y, or y equals that numeral
Read as: either the object language constant zero is less than a, or a is less than that constant, or a equals that constant
Means: either the object language constant zero is less than a, or a is less than that constant, or a equals that constant
Read as: Q proves that A subscript f applied to the numerals for n subscript zero through n subscript k, and the numeral for the value of f at n subscript zero through n subscript k
Means: Q proves that A subscript f applied to the numerals for n subscript zero through n subscript k, and the numeral for the value of f at n subscript zero through n subscript k
Read as: Q proves A subscript g of the numeral for n and the numeral for k, since A subscript g represents g. And Q proves A subscript f of the numeral for k and the numeral for m, since A subscript f represents f. Thus Q proves their conjunction. Consequently Q also proves that there exists y such that both A subscript g of the numeral for n and y, and A subscript f of y and the numeral for m
Means: Q proves A subscript g of the numeral for n and the numeral for k, since A subscript g represents g. And Q proves A subscript f of the numeral for k and the numeral for m, since A subscript f represents f. Thus Q proves their conjunction. Consequently Q also proves that there exists y such that both A subscript g of the numeral for n and y, and A subscript f of y and the numeral for m
Read as: Eight axioms for Q. Q subscript one: for all x and y, if the successor of x equals the successor of y, then x equals y. Q subscript two: for every x, the object language constant zero does not equal the successor of x. Q subscript three: for every x, either x equals the object language constant zero, or there exists y such that x equals the successor of y. Q subscript four: for every x, the sum of x and the object language constant zero equals x. Q subscript five: for all x and y, the sum of x and the successor of y equals the successor of the sum of x and y. Q subscript six: for every x, the object language product of x and the constant zero equals that constant zero. Q subscript seven: for all x and y, the object language product of x and the successor of y equals the sum of the object language product of x and y, and x. Q subscript eight: for all x and y, x is less than y if and only if there exists z such that the sum of the successor of z and x equals y. End of the eight axioms.
Means: Eight axioms for Q. Q subscript one: for all x and y, if the successor of x equals the successor of y, then x equals y. Q subscript two: for every x, the object language constant zero does not equal the successor of x. Q subscript three: for every x, either x equals the object language constant zero, or there exists y such that x equals the successor of y. Q subscript four: for every x, the sum of x and the object language constant zero equals x. Q subscript five: for all x and y, the sum of x and the successor of y equals the successor of the sum of x and y. Q subscript six: for every x, the object language product of x and the constant zero equals that constant zero. Q subscript seven: for all x and y, the object language product of x and the successor of y equals the sum of the object language product of x and y, and x. Q subscript eight: for all x and y, x is less than y if and only if there exists z such that the sum of the successor of z and x equals y. End of the eight axioms.
Read as: z subscript k
Means: z subscript k
Read as: the equality symbol
Means: the equality symbol
Read as: the sum of the successor of the numeral for m and a equals the numeral for m plus one
Means: the sum of the successor of the numeral for m and a equals the numeral for m plus one
Read as: d equals J of d subscript zero and d subscript one
Means: d equals J of d subscript zero and d subscript one
Read as: k equals n plus m
Means: k equals n plus m
Read as: not A subscript g of the numeral for m, the numeral for n, and the object language constant zero
Means: not A subscript g of the numeral for m, the numeral for n, and the object language constant zero
Read as: f of n equals m
Means: f of n equals m
Read as: A applied to x subscript zero through x subscript k, and y
Means: A applied to x subscript zero through x subscript k, and y
Read as: the successor of b is less than the numeral for m plus one
Means: the successor of b is less than the numeral for m plus one
Read as: Q proves that A subscript f applied to the numerals for n subscript zero through n subscript k, and the numeral for l
Means: Q proves that A subscript f applied to the numerals for n subscript zero through n subscript k, and the numeral for l
Read as: there exists z such that the sum of the successor of z and the numeral for m equals b
Means: there exists z such that the sum of the successor of z and the numeral for m equals b
Read as: the numeral for n plus m equals y
Means: the numeral for n plus m equals y
Read as: the standard model N satisfies Q
Means: the standard model N satisfies Q
Read as: A subscript g subscript i applied to x subscript zero through x subscript l minus one, and y
Means: A subscript g subscript i applied to x subscript zero through x subscript l minus one, and y
Read as: the sum of the successor of c and the numeral for m equals b
Means: the sum of the successor of c and the numeral for m equals b
Read as: the zero function applied to x equals zero
Means: the zero function applied to x equals zero
Read as: either a is less than the object language constant zero, or that constant is less than a, or a equals that constant
Means: either a is less than the object language constant zero, or that constant is less than a, or a equals that constant
Read as: Q proves that the finite conjunction of A applied to each numeral from zero through k minus one
Means: Q proves that the finite conjunction of A applied to each numeral from zero through k minus one
Read as: the implication from T to A is provable with no nonlogical premises
Means: the implication from T to A is provable with no nonlogical premises
Read as: m plus one
Means: m plus one
Read as: m equals k plus one
Means: m equals k plus one
Read as: w is less than x
Means: w is less than x
Read as: the numeral for n
Means: the numeral for n
Read as: b is less than the numeral for m
Means: b is less than the numeral for m
Read as: the value of t subscript one in the standard model N does not equal the value of t subscript two in the standard model N
Means: the value of t subscript one in the standard model N does not equal the value of t subscript two in the standard model N
Read as: Q proves that there exists x less than t such that A of x
Means: Q proves that there exists x less than t such that A of x
Read as: A subscript f applied to x subscript zero through x subscript k, and y
Means: A subscript f applied to x subscript zero through x subscript k, and y
Read as: Q proves that the numeral for n does not equal the numeral for m
Means: Q proves that the numeral for n does not equal the numeral for m
Read as: A of x
Means: A of x
Read as: A
Means: A
Read as: k
Means: k
Read as: g of m and n equals zero
Means: g of m and n equals zero
Read as: one plus the product of i plus one and m
Means: one plus the product of i plus one and m
Read as: the successor of the sum of the successor of c and b equals the sum of the successor of c and the successor of b
Means: the successor of the sum of the successor of c and b equals the sum of the successor of c and the successor of b
Read as: the characteristic function of equality applied to n and m equals zero
Means: the characteristic function of equality applied to n and m equals zero
Read as: Q proves that the sum of the numeral for n and the numeral for m plus one equals the numeral for n plus m plus one
Means: Q proves that the sum of the numeral for n and the numeral for m plus one equals the numeral for n plus m plus one
Read as: d subscript one
Means: d subscript one
Read as: d subscript zero
Means: d subscript zero
Read as: Q does not prove that there exists y such that B subscript T holds of the numeral for e, the numeral for n, and y
Means: Q does not prove that there exists y such that B subscript T holds of the numeral for e, the numeral for n, and y
Read as: R holds of n subscript zero through n subscript k, and s, if and only if the entry at position zero in the prime power sequence coded by s is a derivation code in Q for the formula with code A of n subscript zero through n subscript k, and the entry at position one in that sequence
Means: R holds of n subscript zero through n subscript k, and s, if and only if the entry at position zero in the prime power sequence coded by s is a derivation code in Q for the formula with code A of n subscript zero through n subscript k, and the entry at position one in that sequence
Read as: the numerical multiplication operation
Means: the numerical multiplication operation
Read as: Q proves that t subscript two equals the numeral for m
Means: Q proves that t subscript two equals the numeral for m
Read as: the entry at position zero in the prime power sequence coded by s
Means: the entry at position zero in the prime power sequence coded by s
Read as: in the standard model N, t subscript one is less than t subscript two
Means: in the standard model N, t subscript one is less than t subscript two
Read as: b is less than the numeral for n plus one
Means: b is less than the numeral for n plus one
Read as: the value of t subscript one in the standard model N equals the value of t subscript two in the standard model N
Means: the value of t subscript one in the standard model N equals the value of t subscript two in the standard model N
Read as: p divides x subscript k
Means: p divides x subscript k
Read as: the sum of the successor of b and the object language constant zero equals the object language constant zero
Means: the sum of the successor of b and the object language constant zero equals the object language constant zero
Read as: A subscript R applied to the numerals for n subscript zero through n subscript k
Means: A subscript R applied to the numerals for n subscript zero through n subscript k
Read as: p divides m
Means: p divides m
Read as: for every x, if x is less than t then A of x
Means: for every x, if x is less than t then A of x
Read as: A subscript g of b, the numeral for n, and the object language constant zero
Means: A subscript g of b, the numeral for n, and the object language constant zero
Read as: A subscript f of z and y
Means: A subscript f of z and y
Read as: R
Means: R
Read as: m equals zero
Means: m equals zero
Read as: the successor of b equals the object language constant zero
Means: the successor of b equals the object language constant zero
Read as: Q subscript eight
Means: Q subscript eight
Read as: Q proves that t subscript two equals the numeral for n subscript two
Means: Q proves that t subscript two equals the numeral for n subscript two
Read as: the sum of the successor of c and the successor of b equals the successor of the numeral for n plus one
Means: the sum of the successor of c and the successor of b equals the successor of the numeral for n plus one
Read as: a is less than the numeral for m plus one
Means: a is less than the numeral for m plus one
Read as: m equals n
Means: m equals n
Read as: Q proves that the successor of t subscript one equals the successor of the numeral for n subscript one
Means: Q proves that the successor of t subscript one equals the successor of the numeral for n subscript one
Read as: x equals one of the numerals from zero through k
Means: x equals one of the numerals from zero through k
Read as: the numeral for m is less than b
Means: the numeral for m is less than b
Read as: the sum of the successor of b and the object language constant zero equals the successor of b
Means: the sum of the successor of b and the object language constant zero equals the successor of b
Read as: the sum of a and the object language constant zero equals a
Means: the sum of a and the object language constant zero equals a
Read as: n is less than the value of t in the standard model N
Means: n is less than the value of t in the standard model N
Read as: A subscript R applied to x subscript zero through x subscript k
Means: A subscript R applied to x subscript zero through x subscript k
Read as: x and y
Means: x and y
Read as: Q proves that the sum of the numeral for n and the numeral for m equals the numeral for n plus m
Means: Q proves that the sum of the numeral for n and the numeral for m equals the numeral for n plus m
Read as: there exists x such that B of x
Means: there exists x such that B of x
Read as: Q proves that the sum of the numeral for n and the successor of the numeral for m equals the successor of the sum of the numeral for n and the numeral for m
Means: Q proves that the sum of the numeral for n and the successor of the numeral for m equals the successor of the sum of the numeral for n and the numeral for m
Read as: the negation of the conjunction of A and B
Means: the negation of the conjunction of A and B
Read as: Q proves that the sum of the numeral for n and the successor of the numeral for k equals the numeral for m
Means: Q proves that the sum of the numeral for n and the successor of the numeral for k equals the numeral for m
Read as: A subscript f applied to the numerals for n subscript zero through n subscript k, and the numeral for m
Means: A subscript f applied to the numerals for n subscript zero through n subscript k, and the numeral for m
Read as: the numeral for one
Means: the numeral for one
Read as: the value of the successor of t subscript one in the standard model N equals n subscript one plus one
Means: the value of the successor of t subscript one in the standard model N equals n subscript one plus one
Read as: for every x less than the numeral for k plus one, A of x
Means: for every x less than the numeral for k plus one, A of x
Read as: a equals the numeral for m plus one
Means: a equals the numeral for m plus one
Read as: g subscript k minus one
Means: g subscript k minus one
Read as: for every y, if A subscript f holds of the numerals for n subscript zero through n subscript k, and y, then the numeral for l equals y
Means: for every y, if A subscript f holds of the numerals for n subscript zero through n subscript k, and y, then the numeral for l equals y
Read as: both the numeral for n does not equal the numeral for m, and the object language constant zero equals itself
Means: both the numeral for n does not equal the numeral for m, and the object language constant zero equals itself
Read as: Q proves that the numeral for n does not equal the numeral for m
Means: Q proves that the numeral for n does not equal the numeral for m
Read as: h of x and the tuple z
Means: h of x and the tuple z
Read as: Q proves that A of the numeral for n
Means: Q proves that A of the numeral for n
Read as: c divides the difference a minus b
Means: c divides the difference a minus b
Read as: the sum of the successor of c and b equals the numeral for m
Means: the sum of the successor of c and b equals the numeral for m
Read as: there exists z such that the sum of the successor of z and the object language constant zero equals a
Means: there exists z such that the sum of the successor of z and the object language constant zero equals a
Read as: A subscript f applied to x subscript zero through x subscript k minus one, and y
Means: A subscript f applied to x subscript zero through x subscript k minus one, and y
Read as: p divides one plus the product of k plus one and m
Means: p divides one plus the product of k plus one and m
Read as: Sigma one
Means: Sigma one
Read as: a is less than the numeral for n plus two
Means: a is less than the numeral for n plus two
Read as: the second successor of the object language constant zero
Means: the second successor of the object language constant zero
Read as: the partial computable function with index e is defined at n
Means: the partial computable function with index e is defined at n
Read as: There exist y subscript zero through y subscript k minus one such that all of the following hold. A subscript g subscript zero holds of x subscript zero through x subscript l minus one, and y subscript zero. Continue this conjunction through A subscript g subscript k minus one, applied to the same input tuple and y subscript k minus one. Finally A subscript f holds of y subscript zero through y subscript k minus one, and z
Means: There exist y subscript zero through y subscript k minus one such that all of the following hold. A subscript g subscript zero holds of x subscript zero through x subscript l minus one, and y subscript zero. Continue this conjunction through A subscript g subscript k minus one, applied to the same input tuple and y subscript k minus one. Finally A subscript f holds of y subscript zero through y subscript k minus one, and z
Read as: g of e and n
Means: g of e and n
Read as: the value of t in the standard model N equals zero
Means: the value of t in the standard model N equals zero
Read as: Q proves that for every y, either y equals the object language constant zero, or there exists z such that y is the successor of z
Means: Q proves that for every y, either y equals the object language constant zero, or there exists z such that y is the successor of z
Read as: x divides y
Means: x divides y
Read as: for every x, zero is not equal to the successor of x
Means: for every x, zero is not equal to the successor of x
Read as: Q subscript three
Means: Q subscript three
Read as: the successor of the sum of the successor of c and the numeral for m equals the successor of b
Means: the successor of the sum of the successor of c and the numeral for m equals the successor of b
Read as: Q proves that for every y, if A subscript equality holds of the numeral for n, the numeral for m, and y, then y equals the numeral for one
Means: Q proves that for every y, if A subscript equality holds of the numeral for n, the numeral for m, and y, then y equals the numeral for one
Read as: For every y: if both A holds of the object language constant zero, and for every x, A of x implies A of the successor of x, then A holds of every x. The occurrences of y as an additional parameter of A are suppressed in the displayed notation
Means: For every y: if both A holds of the object language constant zero, and for every x, A of x implies A of the successor of x, then A holds of every x. The occurrences of y as an additional parameter of A are suppressed in the displayed notation
Read as: y subscript i is less than x subscript i
Means: y subscript i is less than x subscript i
Read as: Q proves that the object language constant zero equals the numeral for zero
Means: Q proves that the object language constant zero equals the numeral for zero
Read as: Q proves that not both A and B
Means: Q proves that not both A and B
Read as: f of x subscript zero through x subscript k
Means: f of x subscript zero through x subscript k
Read as: R of n subscript zero through n subscript k
Means: R of n subscript zero through n subscript k
Read as: y
Means: y
Read as: g of x
Means: g of x
Read as: the negation of the bounded universal formula with variable x, bound t, and matrix A of x
Means: the negation of the bounded universal formula with variable x, bound t, and matrix A of x
Read as: y equals the object language constant zero
Means: y equals the object language constant zero
Read as: Q subscript two
Means: Q subscript two
Read as: plus
Means: plus
Read as: T
Means: T
Read as: y equals the numeral for zero
Means: y equals the numeral for zero
Read as: y equals the sum of x subscript zero and x subscript one
Means: y equals the sum of x subscript zero and x subscript one
Read as: the sum of the successor of z and the numeral for n equals the numeral for m
Means: the sum of the successor of z and the numeral for n equals the numeral for m
Read as: for every x, x is not equal to its successor
Means: for every x, x is not equal to its successor
Read as: We seek a proof in Q of the conjunction of A subscript g of the numeral for m, the numeral for n, and the object language constant zero, with the statement that every w less than the numeral for m fails to satisfy A subscript g of w, the numeral for n, and that constant zero. Since A subscript g of x, z, and y represents g of x and z, and g of m and n equals zero if f of n equals m, Q proves the first conjunct. If f of n equals m, then for every k less than m, g of k and n is not zero. So Q proves not A subscript g of the numeral for k, the numeral for n, and that constant zero. We obtain the final displayed claim: Q proves that for every w, if w is less than the numeral for m then not A subscript g of w, the numeral for n, and that constant zero
Means: We seek a proof in Q of the conjunction of A subscript g of the numeral for m, the numeral for n, and the object language constant zero, with the statement that every w less than the numeral for m fails to satisfy A subscript g of w, the numeral for n, and that constant zero. Since A subscript g of x, z, and y represents g of x and z, and g of m and n equals zero if f of n equals m, Q proves the first conjunct. If f of n equals m, then for every k less than m, g of k and n is not zero. So Q proves not A subscript g of the numeral for k, the numeral for n, and that constant zero. We obtain the final displayed claim: Q proves that for every w, if w is less than the numeral for m then not A subscript g of w, the numeral for n, and that constant zero
Read as: there exists y such that the sum of the successor of y and a equals the successor of the object language constant zero
Means: there exists y such that the sum of the successor of y and a equals the successor of the object language constant zero
Read as: the sum of the successor of b and c equals the object language constant zero
Means: the sum of the successor of b and c equals the object language constant zero
Read as: Kleene T of e, n, and s
Means: Kleene T of e, n, and s
Read as: Q proves that B
Means: Q proves that B
Read as: x subscript zero equals one plus m. x subscript one equals one plus two times m. x subscript two equals one plus three times m. Continue in this pattern through x subscript n, which equals one plus the product of n plus one and m
Means: x subscript zero equals one plus m. x subscript one equals one plus two times m. x subscript two equals one plus three times m. Continue in this pattern through x subscript n, which equals one plus the product of n plus one and m
Read as: the successor of b equals the successor of the numeral for m
Means: the successor of b equals the successor of the numeral for m
Read as: either b is less than the numeral for m, or the numeral for m is less than b, or b equals the numeral for m
Means: either b is less than the numeral for m, or the numeral for m is less than b, or b equals the numeral for m
Read as: Q proves that the sum of the numeral for n subscript one and the numeral for n subscript two equals the numeral for n subscript one plus n subscript two
Means: Q proves that the sum of the numeral for n subscript one and the numeral for n subscript two equals the numeral for n subscript one plus n subscript two
Read as: a equals one of the numerals from one through n plus one
Means: a equals one of the numerals from one through n plus one
Read as: h
Means: h
Read as: Q proves that the sum of t subscript one and t subscript two equals the sum of the numeral for n subscript one and the numeral for n subscript two
Means: Q proves that the sum of t subscript one and t subscript two equals the sum of the numeral for n subscript one and the numeral for n subscript two
Read as: a equals one of the numerals from zero through n plus one
Means: a equals one of the numerals from zero through n plus one
Read as: Q proves that not the disjunction of A and B
Means: Q proves that not the disjunction of A and B
Read as: the sequence y subscript zero through y subscript n
Means: the sequence y subscript zero through y subscript n
Read as: the successor of the numeral for n
Means: the successor of the numeral for n
Read as: Q proves that t subscript one equals the numeral for n
Means: Q proves that t subscript one equals the numeral for n
Read as: the numeral coding function num
Means: the numeral coding function num
Read as: m equals the value of t subscript two in the standard model N
Means: m equals the value of t subscript two in the standard model N
Read as: Delta zero
Means: Delta zero
Read as: A is the formula for every x, B of x
Means: A is the formula for every x, B of x
Read as: d subscript zero is congruent to a subscript i modulo one plus the product of i plus one and d subscript one
Means: d subscript zero is congruent to a subscript i modulo one plus the product of i plus one and d subscript one
Read as: n subscript zero
Means: n subscript zero
Read as: Q proves that both A and B
Means: Q proves that both A and B
Read as: the standard model N does not satisfy that t subscript one is less than t subscript two
Means: the standard model N does not satisfy that t subscript one is less than t subscript two
Read as: m equals k plus one
Means: m equals k plus one
Read as: the numeral for zero
Means: the numeral for zero
Read as: Q proves that t subscript one equals t subscript two
Means: Q proves that t subscript one equals t subscript two
Read as: the successor of the numeral for m is the numeral for m plus one
Means: the successor of the numeral for m is the numeral for m plus one
Read as: a subscript i equals the remainder when d subscript zero is divided by one plus the product of i plus one and d subscript one
Means: a subscript i equals the remainder when d subscript zero is divided by one plus the product of i plus one and d subscript one
Read as: the addition function
Means: the addition function
Read as: m does not equal f of n subscript zero through n subscript k
Means: m does not equal f of n subscript zero through n subscript k
Read as: Q proves that for every x less than the numeral for k plus one, A of x
Means: Q proves that for every x less than the numeral for k plus one, A of x
Read as: Step five. Q proves that the sum of the successor of a and the successor of the numeral for n equals the successor of the sum of the successor of a and the numeral for n, by axiom Q subscript five. Step six, attributed in the source to the induction hypothesis. Q proves that the sum of the successor of a and the successor of the numeral for n equals the successor of the sum of a and the successor of the numeral for n. Final source line. Q proves that the successor of the sum of the successor of a and the numeral for n equals the successor of the sum of a and the successor of the numeral for n, by step five of the successor and fixed numeral addition derivation and step six of the successor and fixed numeral addition derivation
Means: Step five. Q proves that the sum of the successor of a and the successor of the numeral for n equals the successor of the sum of the successor of a and the numeral for n, by axiom Q subscript five. Step six, attributed in the source to the induction hypothesis. Q proves that the sum of the successor of a and the successor of the numeral for n equals the successor of the sum of a and the successor of the numeral for n. Final source line. Q proves that the successor of the sum of the successor of a and the numeral for n equals the successor of the sum of a and the successor of the numeral for n, by step five of the successor and fixed numeral addition derivation and step six of the successor and fixed numeral addition derivation
Read as: for every x less than t, A of x
Means: for every x less than t, A of x
Read as: if the successor of the numeral for n equals the successor of the numeral for k, then the numeral for n equals the numeral for k
Means: if the successor of the numeral for n equals the successor of the numeral for k, then the numeral for n equals the numeral for k
Read as: the standard model N satisfies A of the numeral for n
Means: the standard model N satisfies A of the numeral for n
Read as: Q proves that A subscript g of the numeral for m, the numeral for n, and the object language constant zero
Means: Q proves that A subscript g of the numeral for m, the numeral for n, and the object language constant zero
Read as: the numeral for one is the successor of the object language constant zero
Means: the numeral for one is the successor of the object language constant zero
Read as: the object language constant zero
Means: the object language constant zero
Read as: Q proves: for every y, if A subscript g holds of the numeral for n and y, then y equals the numeral for k; since A subscript g represents g. And Q proves: for every z, if A subscript f holds of the numeral for k and z, then z equals the numeral for m; since A subscript f represents f. Using logic, Q also proves: for every z, if there exists y such that both A subscript g of the numeral for n and y, and A subscript f of y and z, then z equals the numeral for m
Means: Q proves: for every y, if A subscript g holds of the numeral for n and y, then y equals the numeral for k; since A subscript g represents g. And Q proves: for every z, if A subscript f holds of the numeral for k and z, then z equals the numeral for m; since A subscript f represents f. Using logic, Q also proves: for every z, if there exists y such that both A subscript g of the numeral for n and y, and A subscript f of y and z, then z equals the numeral for m
Read as: t subscript one
Means: t subscript one
Read as: the sum of the successor of b and the successor of c equals the successor of the object language constant zero
Means: the sum of the successor of b and the successor of c equals the successor of the object language constant zero
Read as: Q proves that t subscript one does not equal t subscript two
Means: Q proves that t subscript one does not equal t subscript two
Read as: Q proves that both the numeral for n equals the numeral for m, and the numeral for one equals itself
Means: Q proves that both the numeral for n equals the numeral for m, and the numeral for one equals itself
Read as: m is less than n
Means: m is less than n
Read as: d subscript one equals the least common multiple of the integers one through j
Means: d subscript one equals the least common multiple of the integers one through j
Read as: Pi one
Means: Pi one
Read as: the object language product of the numeral for m and the numeral for n
Means: the object language product of the numeral for m and the numeral for n
Read as: A subscript Mult of x subscript zero, x subscript one, and y is the formula y equals the object language product of x subscript zero and x subscript one
Means: A subscript Mult of x subscript zero, x subscript one, and y is the formula y equals the object language product of x subscript zero and x subscript one
Read as: Q proves that B subscript T applied to the numerals for e, n, and s
Means: Q proves that B subscript T applied to the numerals for e, n, and s
Read as: A subscript characteristic function of R, applied to the numerals for n subscript zero through n subscript k, and the numeral for one
Means: A subscript characteristic function of R, applied to the numerals for n subscript zero through n subscript k, and the numeral for one
Read as: the successor of the numeral for n subscript one equals the successor of the numeral for n subscript one
Means: the successor of the numeral for n subscript one equals the successor of the numeral for n subscript one
Read as: not A
Means: not A
Read as: Q proves that A subscript Add applied to the numeral for n, the numeral for m, and the numeral for k
Means: Q proves that A subscript Add applied to the numeral for n, the numeral for m, and the numeral for k
Read as: Q proves that the sum of the numeral for n and the numeral for m equals the numeral for n plus m
Means: Q proves that the sum of the numeral for n and the numeral for m equals the numeral for n plus m
Read as: K of z equals the least x less than or equal to z such that there exists y less than or equal to z with z equal to J of x and y. L of z equals the least y less than or equal to z such that there exists x less than or equal to z with z equal to J of x and y
Means: K of z equals the least x less than or equal to z such that there exists y less than or equal to z with z equal to J of x and y. L of z equals the least y less than or equal to z such that there exists x less than or equal to z with z equal to J of x and y
Read as: Q proves that there exists x such that A of x
Means: Q proves that there exists x such that A of x
Read as: s equals the prime power code of the ordered pair consisting of the Goedel number of delta and the number f of n subscript zero through n subscript k
Means: s equals the prime power code of the ordered pair consisting of the Goedel number of delta and the number f of n subscript zero through n subscript k
Read as: R of x subscript zero through x subscript k
Means: R of x subscript zero through x subscript k
Read as: Q proves that for every y, either y is less than the numeral for m, or the numeral for m is less than y, or y equals the numeral for m
Means: Q proves that for every y, either y is less than the numeral for m, or the numeral for m is less than y, or y equals the numeral for m
Read as: the value of t in the standard model N equals k plus one
Means: the value of t in the standard model N equals k plus one
Read as: A subscript R applied to x subscript zero through x subscript k
Means: A subscript R applied to x subscript zero through x subscript k
Read as: j equals the maximum of n, a subscript zero plus one, and so on through a subscript n plus one
Means: j equals the maximum of n, a subscript zero plus one, and so on through a subscript n plus one
Read as: the entry at position one in the prime power sequence coded by s
Means: the entry at position one in the prime power sequence coded by s
Read as: a
Means: a
Read as: n plus one does not equal k plus one
Means: n plus one does not equal k plus one
Read as: the numeral for m plus one is less than a
Means: the numeral for m plus one is less than a
Read as: A subscript f of z and y is the conjunction of A subscript g of y, z, and the object language constant zero, with the following universal statement: for every w, if w is less than y then not A subscript g of w, z, and the object language constant zero
Means: A subscript f of z and y is the conjunction of A subscript g of y, z, and the object language constant zero, with the following universal statement: for every w, if w is less than y then not A subscript g of w, z, and the object language constant zero
Read as: Q proves that the sum of the successor of a and the numeral for n equals the successor of the sum of a and the numeral for n
Means: Q proves that the sum of the successor of a and the numeral for n equals the successor of the sum of a and the numeral for n
Read as: for every y, if A subscript f holds of the numerals for n subscript zero through n subscript k, and y, then the numeral for m equals y
Means: for every y, if A subscript f holds of the numerals for n subscript zero through n subscript k, and y, then the numeral for m equals y
Read as: g
Means: g
Read as: g of the tuple x, y, and z
Means: g of the tuple x, y, and z
Read as: A of x and y
Means: A of x and y
Read as: h of e and n equals one if g of e and n is the Goedel number of a sentence provable in Q, and equals zero otherwise
Means: h of e and n equals one if g of e and n is the Goedel number of a sentence provable in Q, and equals zero otherwise
Read as: n subscript k
Means: n subscript k
Read as: Q proves that the sum of the successor of a and the numeral for n equals the successor of the sum of a and the numeral for n
Means: Q proves that the sum of the successor of a and the numeral for n equals the successor of the sum of a and the numeral for n
Read as: B
Means: B
Read as: k equals the value of t in the standard model N
Means: k equals the value of t in the standard model N
Read as: R of n subscript zero through n subscript k
Means: R of n subscript zero through n subscript k
Read as: if a is less than the numeral for one, then a equals the object language constant zero
Means: if a is less than the numeral for one, then a equals the object language constant zero
Read as: Beta of d and i equals beta star of d subscript zero, d subscript one, and i. This equals the remainder when d subscript zero is divided by one plus the product of i plus one and d subscript one. This equals a subscript i
Means: Beta of d and i equals beta star of d subscript zero, d subscript one, and i. This equals the remainder when d subscript zero is divided by one plus the product of i plus one and d subscript one. This equals a subscript i
Read as: Q proves that the numeral for n is less than the numeral for k plus one
Means: Q proves that the numeral for n is less than the numeral for k plus one
Read as: J of x and y equals one half of the product of x plus y and x plus y plus one, plus x
Means: J of x and y equals one half of the product of x plus y and x plus y plus one, plus x
Read as: delta
Means: delta
Read as: T
Means: T
Read as: The characteristic function of equality applied to x subscript zero and x subscript one has two cases: one if x subscript zero equals x subscript one; zero otherwise
Means: The characteristic function of equality applied to x subscript zero and x subscript one has two cases: one if x subscript zero equals x subscript one; zero otherwise
Read as: the addition function applied to n and m equals k
Means: the addition function applied to n and m equals k
Read as: the sum of the successor of c and b equals the numeral for n plus one
Means: the sum of the successor of c and b equals the numeral for n plus one
Read as: the sum of the successor of z and the numeral for n minus m equals the object language constant zero
Means: the sum of the successor of z and the numeral for n minus m equals the object language constant zero
Read as: Q subscript four
Means: Q subscript four
Read as: the numeral for n plus m
Means: the numeral for n plus m
Read as: the entry beta of d and i in the beta coding
Means: the entry beta of d and i in the beta coding
Read as: beta of d and i equals a subscript i
Means: beta of d and i equals a subscript i
Read as: x is less than y
Means: x is less than y
Read as: two
Means: two
Read as: A of the numeral for n
Means: A of the numeral for n
Read as: y equals g of x
Means: y equals g of x
Read as: the sum of x subscript zero and x subscript one equals y
Means: the sum of x subscript zero and x subscript one equals y
Read as: Q proves that A or B
Means: Q proves that A or B
Read as: the sum of the successor of b and the object language constant zero equals a
Means: the sum of the successor of b and the object language constant zero equals a
Read as: p divides x subscript i
Means: p divides x subscript i
Read as: i is less than or equal to n
Means: i is less than or equal to n
Read as: P A
Means: P A
Read as: h of x subscript zero through x subscript l minus one equals f applied to the outputs of g subscript zero through g subscript k minus one, each evaluated on that same input tuple x subscript zero through x subscript l minus one
Means: h of x subscript zero through x subscript l minus one equals f applied to the outputs of g subscript zero through g subscript k minus one, each evaluated on that same input tuple x subscript zero through x subscript l minus one
Read as: less than
Means: less than
Read as: A subscript f applied to the numerals for n subscript zero through n subscript k, and the numeral for the entry at position one in the prime power sequence coded by s
Means: A subscript f applied to the numerals for n subscript zero through n subscript k, and the numeral for the entry at position one in the prime power sequence coded by s
Read as: a equals the successor of c
Means: a equals the successor of c
Read as: Beta star of d subscript zero, d subscript one, and i equals the remainder when d subscript zero is divided by one plus the product of i plus one and d subscript one. Beta of d and i equals beta star of K of d, L of d, and i
Means: Beta star of d subscript zero, d subscript one, and i equals the remainder when d subscript zero is divided by one plus the product of i plus one and d subscript one. Beta of d and i equals beta star of K of d, L of d, and i
Read as: y subscript zero
Means: y subscript zero
Read as: the multiplication function
Means: the multiplication function
Read as: the value of t in the standard model N equals n
Means: the value of t in the standard model N equals n
Read as: i
Means: i
Read as: A subscript characteristic function of R, applied to x subscript zero through x subscript k, and y
Means: A subscript characteristic function of R, applied to x subscript zero through x subscript k, and y
Read as: the characteristic function of equality
Means: the characteristic function of equality
Read as: f of x subscript zero through x subscript k
Means: f of x subscript zero through x subscript k
Read as: n plus k plus one equals m
Means: n plus k plus one equals m
Read as: the numeral for zero does not equal the numeral for one
Means: the numeral for zero does not equal the numeral for one
Read as: the set of formulas A such that Q proves A
Means: the set of formulas A such that Q proves A
Read as: l equals f of n subscript zero through n subscript k
Means: l equals f of n subscript zero through n subscript k
Read as: not B
Means: not B
Read as: either the numeral for n equals the numeral for m and y equals the numeral for one; or the numeral for n does not equal the numeral for m and y equals the numeral for zero
Means: either the numeral for n equals the numeral for m and y equals the numeral for one; or the numeral for n does not equal the numeral for m and y equals the numeral for zero
Read as: t
Means: t
Read as: n equals the value of t subscript one in the standard model N
Means: n equals the value of t subscript one in the standard model N
Read as: t subscript one is less than t subscript two
Means: t subscript one is less than t subscript two
Read as: h of x equals z
Means: h of x equals z
Read as: y equals the numeral for one
Means: y equals the numeral for one
Read as: T
Means: T
Read as: the sum of the successor of c and the numeral for m plus one equals a
Means: the sum of the successor of c and the numeral for m plus one equals a
Read as: one plus d subscript one
Means: one plus d subscript one
Read as: Q proves that A holds of every numeral from zero through k, as a finite conjunction
Means: Q proves that A holds of every numeral from zero through k, as a finite conjunction
Read as: The sum of the numeral for n and the numeral for m equals the numeral for the number n plus m. And for every y, if that sum equals y, then y equals the numeral for n plus m
Means: The sum of the numeral for n and the numeral for m equals the numeral for the number n plus m. And for every y, if that sum equals y, then y equals the numeral for n plus m
Read as: the successor of the sum of the successor of b and c equals the successor of the object language constant zero
Means: the successor of the sum of the successor of b and c equals the successor of the object language constant zero
Read as: the characteristic function of R
Means: the characteristic function of R
Read as: Q proves that the numeral for n does not equal the numeral for m
Means: Q proves that the numeral for n does not equal the numeral for m
Read as: there exists z such that the sum of the successor of z and b equals the numeral for m
Means: there exists z such that the sum of the successor of z and b equals the numeral for m
Read as: the numeral for n plus m plus one
Means: the numeral for n plus m plus one
Read as: Q proves that t subscript one equals the numeral for n subscript one
Means: Q proves that t subscript one equals the numeral for n subscript one
Read as: Q proves that for every x less than t, A of x
Means: Q proves that for every x less than t, A of x
Read as: A subscript projection function with arity n and index i, applied to x subscript zero through x subscript n minus one and y, is the formula y equals x subscript i
Means: A subscript projection function with arity n and index i, applied to x subscript zero through x subscript n minus one and y, is the formula y equals x subscript i
Read as: the successor of x subscript zero equals y
Means: the successor of x subscript zero equals y
Read as: the value of t subscript two in the standard model N equals n subscript two
Means: the value of t subscript two in the standard model N equals n subscript two
Read as: i is less than y
Means: i is less than y
Read as: Q subscript two
Means: Q subscript two
Read as: Q proves that for every x, it is not the case that x is less than the object language constant zero
Means: Q proves that for every x, it is not the case that x is less than the object language constant zero
Read as: n is less than or equal to k
Means: n is less than or equal to k
Read as: Q proves that there exists y such that B subscript T holds of the numeral for e, the numeral for n, and y
Means: Q proves that there exists y such that B subscript T holds of the numeral for e, the numeral for n, and y
Read as: A is the formula t subscript one is less than t subscript two
Means: A is the formula t subscript one is less than t subscript two
Read as: Q proves that not A
Means: Q proves that not A
Read as: the successor of b equals one of the successors of the numerals from zero through n
Means: the successor of b equals one of the successors of the numerals from zero through n
Read as: the successor of b does not equal the object language constant zero
Means: the successor of b does not equal the object language constant zero
Read as: the sequence consisting of h of the tuple x and zero, h of the tuple x and one, and so on through h of the tuple x and y
Means: the sequence consisting of h of the tuple x and zero, h of the tuple x and one, and so on through h of the tuple x and y
Read as: the numeral for k
Means: the numeral for k
Read as: beta
Means: beta
Read as: for every y, if A subscript characteristic function of R holds of the numerals for n subscript zero through n subscript k, and y, then y equals the numeral for zero
Means: for every y, if A subscript characteristic function of R holds of the numerals for n subscript zero through n subscript k, and y, then y equals the numeral for zero
Read as: the existential formula with bound variable y and matrix consisting of A subscript g of x and y, conjoined with A subscript f of y and z
Means: the existential formula with bound variable y and matrix consisting of A subscript g of x and y, conjoined with A subscript f of y and z
Read as: b equals the numeral for m
Means: b equals the numeral for m
Read as: the object language constant zero followed by the displayed sequence of successor marks
Means: the object language constant zero followed by the displayed sequence of successor marks
Read as: m times n
Means: m times n
Read as: Q proves that there exists z such that the sum of the successor of z and t subscript one equals t subscript two
Means: Q proves that there exists z such that the sum of the successor of z and t subscript one equals t subscript two
Read as: either the numeral for n equals itself and y equals the numeral for one; or the numeral for n does not equal itself and y equals the numeral for zero
Means: either the numeral for n equals itself and y equals the numeral for one; or the numeral for n does not equal itself and y equals the numeral for zero
Read as: it is not the case that a is less than the object language constant zero
Means: it is not the case that a is less than the object language constant zero
Read as: not A subscript R applied to the numerals for n subscript zero through n subscript k
Means: not A subscript R applied to the numerals for n subscript zero through n subscript k
Read as: the successor of the sum of the successor of c and b equals the successor of the numeral for m
Means: the successor of the sum of the successor of c and b equals the successor of the numeral for m
Read as: the sum of the successor of a and the successor of the numeral for n equals the successor of the sum of a and the successor of the numeral for n
Means: the sum of the successor of a and the successor of the numeral for n equals the successor of the sum of a and the successor of the numeral for n
Read as: the substitution coding function Subst
Means: the substitution coding function Subst
Read as: Three definitions without primitive recursion. Not of x is defined to be the characteristic function of equality applied to x and zero. The bounded minimum of x less than or equal to z such that R of x and y is defined to be the least x such that either R of x and y or x equals z. The bounded existential statement that there is x less than or equal to z such that R of x and y holds is defined to mean that R holds of that bounded minimum and y. End of the three definitions
Means: Three definitions without primitive recursion. Not of x is defined to be the characteristic function of equality applied to x and zero. The bounded minimum of x less than or equal to z such that R of x and y is defined to be the least x such that either R of x and y or x equals z. The bounded existential statement that there is x less than or equal to z such that R of x and y holds is defined to mean that R holds of that bounded minimum and y. End of the three definitions
Read as: the successor of the numeral for n does not equal the successor of the numeral for k
Means: the successor of the numeral for n does not equal the successor of the numeral for k
Read as: Q proves that not B
Means: Q proves that not B
Read as: the conjunction of A and B
Means: the conjunction of A and B
The eight universally quantified axioms govern successor injectivity, zero not being a successor, every nonzero object being a successor, recursive addition and multiplication, and less than. The associated expression reads every axiom and its label in order. There is no induction axiom here.
A formula with input variables and one output variable represents a function when, for each actual input tuple and output value, Q proves the formula on the corresponding numerals and proves that any output satisfying it equals that output numeral. Both clauses are required; the universal uniqueness clause is inside Q, while the choice of numerical inputs is metatheoretic.
The theorem has two directions. The chapter first computes representable functions by searching through coded proofs, then represents all general recursive functions using basic arithmetic functions, composition, and regular minimization. The theorem is stated here and proved by the subsequent sections.
For a function represented in Q, the instance of its representing formula on input and output numerals is provable exactly when that output is the actual function value. The source proof combines representability, uniqueness, provability of inequality of distinct numerals, and consistency of Q from its standard model.
The proof first describes a search for a derivation of a numeral instance of the representing formula. It then makes the search numerical using substitution codes, the primitive recursive proof relation, and regular minimization of codes of proof and output pairs. A proof exists for every input, and the preceding lemma ensures that its output is correct.
Start with the Goedel number of the representing formula. Substitute the appropriate numeral code for each input variable in order, then the output numeral code for the output variable. The display is a nested functional definition, not a derivation tree. The associated speech preserves the distinction between each numerical input, its numeral, and that numeral code.
There is a function beta such that every finite sequence can be decoded from some natural number d: beta of d and i returns the entry at position i. Beta is definable using basic functions, composition, and regular minimization, without primitive recursion. This coding is explicitly different from the earlier prime power coding. The lemma asserts existence of a suitable code, not an algorithm constructing that code within the restricted resources.
Two natural numbers are relatively prime when their greatest common divisor is one. The definition concerns common divisors; it does not require that either number itself be prime.
The definition says that a and b are congruent modulo c when c divides their difference, equivalently when they have the same remainder on division by c. The modular parameter and the direction of division are retained.
Given pairwise relatively prime moduli x subscript zero through x subscript n and arbitrary residues y subscript zero through y subscript n, there exists a number z satisfying all the displayed congruences simultaneously. The source also identifies this as the theorem traditionally called the Chinese Remainder Theorem.
Every row uses the same unknown z. Row i says that z is congruent to y subscript i modulo x subscript i, for indices zero through n. The rows are simultaneous conditions, not successive transformations of z.
j is the maximum of n and one greater than each proposed residue. m is the least common multiple of the integers from one through j. These choices are used to construct moduli larger than their residues and pairwise relatively prime.
The modulus with index i is one plus the product of i plus one and m. The display gives the first three members and the final member. Its continuation preserves both the index shift by one and the added one outside the product.
Three displayed definitions express the numerical Boolean not function, a bounded minimum with endpoint fallback, and a bounded existential relation. The last definition tests R at the bounded minimum. The endpoint z ensures termination of the unbounded search used inside the bounded minimum.
K searches for the first coordinate of a pair coded by z; L searches for the second. Each search and its witnessing quantifier is bounded by z. Both tests use the same pairing function J with its argument order x then y.
Beta star takes a residue code, a modulus spacing parameter, and an index, and returns the remainder modulo one plus the product of the index plus one and the spacing parameter. Beta first extracts the two coordinates of d using K and L. The first argument of rem is the divisor, not the dividend.
The three equal quantities are beta of d and i, beta star of the two coordinates and i, and the appropriate remainder, which equals a subscript i. Sunzi theorem and the previously selected bounds supply the final equality.
The source asks the reader to define less than, divisibility, and rem without primitive recursion. The permitted resources are zero, successor, addition, multiplication, the characteristic function of equality, projections, bounded minimization, and bounded quantification. No solution is supplied here.
The base value at last argument zero is f of the parameter tuple. The value at last argument y plus one is g of the parameter tuple, y, and the previous value h at y. The parameter tuple is unchanged in both equations.
A function defined by primitive recursion from f and g can instead be defined using those functions, zero, successor, projections, addition, multiplication, the characteristic function of equality, composition, and regular minimization. The proof searches for a beta code of a finite sequence satisfying the recursion and then decodes its last entry.
The first requirement states the correct sum of two numerals. The second universally quantifies the output variable and says any output equal to that sum equals the numeral of the numerical sum. These are the value and uniqueness conditions for representability.
The zero function maps every input to zero. Its representing formula says that the output variable equals the object language constant zero. The input variable need not occur in this formula.
The successor function maps x to x plus one. Its representing formula says that the output variable equals the successor term on the input variable.
The projection function with arity n and index i returns input coordinate i. Its representing formula states equality of the output variable with that coordinate. The indexing runs from zero to n minus one.
Prove that the three displayed equality formulas represent zero, successor, and the indicated projection, respectively. The proof is left to the reader; no solution is added.
The numerical function returns one for equal inputs and zero otherwise. The representing formula is a disjunction: equal input terms together with output numeral one, or unequal input terms together with output numeral zero. The proof separates the equal and unequal cases and verifies uniqueness in each.
For any two distinct natural numbers, Q proves that their numerals are unequal. The proof is by external induction on one of the numbers, using the successor axioms. It does not assert that Q internally proves a universally quantified inequality principle by induction.
The numerical addition function is represented by equality between the output variable and the object language sum of the two input variables. The following numerical evaluation lemma supplies the value condition, and equality reasoning supplies uniqueness.
Q proves that the object language sum of the numeral for n and the numeral for m equals the numeral for the number n plus m. The proof uses external induction on m, with the zero and successor axioms for addition.
The numerical multiplication function is represented by equality between the output variable and the object language product of the input variables. The proof is marked Exercise in the source and remains unsolved.
Q proves that the object language product of the numerals for n and m equals the numeral for their numerical product. The proof is marked Exercise in the source and is not filled in.
Prove the preceding lemma that Q evaluates products of numerals. The lemma reference is retained, and the source exercise remains unsolved.
Use the numeral multiplication lemma to prove representability of multiplication. Both source references are retained; no new proof is supplied.
For the unary composition h of x equal to f of g of x, whenever h of n equals m, Q proves the proposed representing formula on the numerals for n and m. The proof uses the actual intermediate value k equal to g of n as an existential witness.
Q proves the two representing instances for g and f, then their conjunction, then existentially quantifies the intermediate value. Interleaved source explanations identify which representing formula justifies each initial instance. The displayed steps form a linear derivation.
When h of n equals m, Q proves that every output z satisfying the proposed formula for h equals the numeral for m. The proof applies the uniqueness properties of g and f in sequence.
The first universal statement forces the intermediate variable y to equal the numeral for k. The second forces z to equal the numeral for m. Logic then yields the universal uniqueness statement for the existentially composed formula. Quantifier scopes remain attached to their own conclusions.
For a function f of k inputs and inner functions each of l inputs, existentially bind k intermediate variables. Conjoin every representing formula for the inner functions at the shared input tuple with the representing formula for f at those intermediate values and the output. The proof is marked Exercise and remains unsolved.
There is one existential intermediate variable for each inner function. All inner representing formulas and the outer representing formula belong within the scope of all these quantifiers. The displayed ellipsis abbreviates the intervening conjunctions in index order.
Give the detailed proof of representability for general composition, using the preceding unary arguments as a guide. The source repeats the reference to the uniqueness proposition; that source reference defect is disclosed rather than silently changed. No solution is supplied.
For any constant a and natural number n, Q proves that the sum of the successor of a and the numeral for n equals the successor of the sum of a and that numeral. The parentheses are essential: the successor on the right applies to the whole sum. The source inductive derivation has a disclosed misidentified step and is preserved without a replacement proof.
Two instances of the addition zero axiom identify the two sums. Applying successor to one equality and combining equalities gives the target base case. Four displayed lines retain their step labels and dependencies.
The source presents step five from the addition successor axiom, step six attributed to induction, and a final equality attributed to both steps. The line labeled step six is already the desired successor case rather than the induction hypothesis. The source lines and this caveat are preserved; they are not treated as an independently verified proof.
The lemma universally negates being less than the object language constant zero. The source proof expands the definition of less than, separates the zero and successor cases, and derives contradictions with the zero and successor axioms.
For every natural number n, Q proves that anything less than the numeral for n plus one equals one of the numerals zero through n. The external induction establishes a finite disjunction inside Q for each chosen bound.
For every natural number m, Q proves that each y is less than the numeral for m, greater than it, or equal to it. This is a separate provability claim for each numeral, proved by external induction; it is not stated as unrestricted internal trichotomy for two arbitrary variables.
The first displayed universal trichotomy is against the numeral for m. The second, introduced as the goal, is against the numeral for m plus one. Each has the same three alternatives in the same order.
Given the representing formula for a regular function g, the formula for its least zero requires g to have value zero at the proposed output and not to have value zero at any smaller number. The universal bounded condition ensures leastness. The surrounding hypothesis of regularity ensures the numerical function is total.
The derivation combines the provable zero instance at the actual minimum with the negations of all smaller numeral instances. The finite numeral bound lemmas then yield the universal statement excluding every smaller object. Source explanations between rows are part of the linear reading, not omitted captions.
Using general recursive functions as the precise model of computation, replace primitive recursion with the established simulation, represent each basic function, and apply closure under composition and regular minimization. The accompanying discussion distinguishes representability from the strength of a theory in proving arbitrary sentences.
A formula represents a relation when Q proves its numeral instance whenever the relation holds, and proves the negation of that instance whenever the relation does not hold. Both positive and negative instances are required.
The forward direction searches in parallel for a proof of the positive or negative instance. The backward direction represents the computable characteristic function and fixes its output argument to numeral one. Its unique output zero in the false case gives the required negative instance.
Show that representability of R implies representability of its characteristic function. The source leaves this direction as an exercise, and no proof is added.
The provability relation restricts y to sentence codes and asserts existence of a derivation code in Q. The theorem says this relation is not recursive. The proof reduces halting to whether a sentence asserting a Kleene T witness is provable, using the standard model of Q to exclude false existential conclusions.
Because Q has finitely many axioms, provability from Q can be reduced to logical provability of an implication whose antecedent is the conjunction of those axioms. A decision procedure for first order logic would therefore decide Q, contradicting the preceding theorem.
A bounded existential requires both x less than its bound and A of x. A bounded universal says that x less than the bound implies A of x. Their compact bounded quantifier notations preserve these different connectives. The usual restriction that the bound not depend on the quantified variable is not stated in the source, and this omission is disclosed.
Delta zero formulas are built from atomic formulas by propositional connectives and bounded quantification. In the displayed definitions a Sigma one formula has an existential quantifier before a Delta zero formula, while a Pi one formula has a universal quantifier before a Delta zero formula.
For a closed arithmetic term whose value in the standard model is n, Q proves its equality with the numeral for n. The proof uses structural induction on terms, the equality rules, and the previously established numeral arithmetic facts. The multiplication case is explicitly left for the following exercise.
Give the detailed multiplication case of the closed term evaluation lemma. The source reference and the multiplication symbol are retained, and no solution is added.
Four clauses cover equal standard values, unequal standard values, strict less than, and failure of strict less than. They conclude provability in Q of the corresponding equality, inequality, order statement, or negated order statement. The source proof contains a numeral index typo and incorrect contradiction axiom references; these are disclosed without claiming the printed steps are correct.
If the closed bound has standard value k, a bounded universal is provable exactly when the conjunction of its numeral instances from zero through k minus one is provable. The existential counterpart uses their disjunction. The source proof treats the universal case and leaves the existential case to an exercise. Its zero bound paragraph misnames the empty conjunction as a disjunction; the mismatch is disclosed.
Give the detailed existential case of the bounded quantifier equivalence lemma. The exercise remains unsolved.
Every Delta zero sentence true in the standard model is provable in Q. The source proof proceeds by formula complexity, separates positive and negated connective cases, reduces bounded quantifiers to finite combinations, and handles atomic negations and double negation. It leaves the detailed existential case for the following exercise.
Give the detailed existential case of the Delta zero completeness lemma. No solution is supplied in the source or added by this edition.
Every Sigma one sentence true in the standard model is provable in Q. Choose its standard numerical witness, substitute the corresponding numeral into the Delta zero matrix, apply Delta zero completeness, and introduce the existential quantifier. The source satisfaction statement explicitly uses assignment s for the free variable before numeral substitution.
the soundness corollary that satisfiable theories are consistent, for axiomatic derivations
the soundness corollary that satisfiable theories are consistent, for sequent calculus
the soundness corollary that satisfiable theories are consistent, for natural deduction
the soundness corollary that satisfiable theories are consistent, for tableaux
the lemma equating provable representing instances with correct function values
the lemma equating provable representing instances with correct function values
the proposition that substitution coding is primitive recursive
the first observation, that the chosen moduli are relatively prime
the second observation, that each residue is smaller than its modulus
the first observation, that the chosen moduli are relatively prime
the second observation, that each residue is smaller than its modulus
the proposition representing the characteristic function of equality
the proposition giving the uniqueness clause for unary composition
the proposition giving the uniqueness clause for unary composition
step two of the successor and fixed numeral addition derivation
step one of the successor and fixed numeral addition derivation
step three of the successor and fixed numeral addition derivation
step five of the successor and fixed numeral addition derivation
step six of the successor and fixed numeral addition derivation
the lemma simulating primitive recursion by regular minimization
the proposition representing the characteristic function of equality
the theorem that function representability in Q is equivalent to computability