Expression 1
Conventional reading: Ax sub zero
Meaning here: Ax sub zero is the named set containing every propositional axiom instance generated by the fourteen displayed schemes.
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Axiomatic Deduction
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All 146 stable expression records, 44 formal objects, five derivations, five unsolved exercises, and 57 resolved references are indexed here.
Conventional reading: Ax sub zero
Meaning here: Ax sub zero is the named set containing every propositional axiom instance generated by the fourteen displayed schemes.
Conventional reading: A sub k
Meaning here: A sub k is a second earlier formula used to justify step A sub i.
Conventional reading: the complete formula A is axiomatically derivable from the premise set containing not not A
Meaning here: The statement is read 'the complete formula A is axiomatically derivable from the premise set containing not not A'. It asserts or denies the existence of a finite axiomatic derivation with the displayed premise set and conclusion.
Conventional reading: open parenthesis E implies open parenthesis D implies E close parenthesis close parenthesis implies open parenthesis open parenthesis not D or E close parenthesis implies open parenthesis D implies E close parenthesis close parenthesis
Meaning here: The complete propositional formula is read 'open parenthesis E implies open parenthesis D implies E close parenthesis close parenthesis implies open parenthesis open parenthesis not D or E close parenthesis implies open parenthesis D implies E close parenthesis close parenthesis'. Spoken parentheses and connective names preserve its printed logical scope.
Conventional reading: the complete formula not A implies open parenthesis A implies falsum close parenthesis is derivable with no premises
Meaning here: The statement is read 'the complete formula not A implies open parenthesis A implies falsum close parenthesis is derivable with no premises'. It asserts or denies the existence of a finite axiomatic derivation with the displayed premise set and conclusion.
Conventional reading: the complete formula open parenthesis not A implies falsum close parenthesis implies not not A is axiomatically derivable from premise set Gamma
Meaning here: The statement is read 'the complete formula open parenthesis not A implies falsum close parenthesis implies not not A is axiomatically derivable from premise set Gamma'. It asserts or denies the existence of a finite axiomatic derivation with the displayed premise set and conclusion.
The source form is preserved; the reader projection is separately disclosed.
Conventional reading: the complete formula open parenthesis A implies B close parenthesis implies open parenthesis open parenthesis B implies C close parenthesis implies open parenthesis A implies C close parenthesis close parenthesis is derivable with no premises
Meaning here: The statement is read 'the complete formula open parenthesis A implies B close parenthesis implies open parenthesis open parenthesis B implies C close parenthesis implies open parenthesis A implies C close parenthesis close parenthesis is derivable with no premises'. It asserts or denies the existence of a finite axiomatic derivation with the displayed premise set and conclusion.
Conventional reading: B sub l equals B
Meaning here: The equation is read 'B sub l equals B'. It identifies the indexed derivation formula with the named final formula.
Conventional reading: n
Meaning here: n is the terminal index of the finite derivation.
Conventional reading: Gamma equals the set containing A implies B comma B implies C
Meaning here: Gamma is defined as the two-premise set containing the conditional from A to B and the conditional from B to C.
Conventional reading: B implies A sub i
Meaning here: The complete propositional formula is read 'B implies A sub i'. Spoken parentheses and connective names preserve its printed logical scope.
Conventional reading: the complete formula falsum is axiomatically derivable from premise set Gamma
Meaning here: The statement is read 'the complete formula falsum is axiomatically derivable from premise set Gamma'. It asserts or denies the existence of a finite axiomatic derivation with the displayed premise set and conclusion.
Conventional reading: D implies B
Meaning here: The complete propositional formula is read 'D implies B'. Spoken parentheses and connective names preserve its printed logical scope.
Conventional reading: the complete formula B is axiomatically derivable from premise A
Meaning here: The statement is read 'the complete formula B is axiomatically derivable from premise A'. It asserts or denies the existence of a finite axiomatic derivation with the displayed premise set and conclusion.
Conventional reading: valuation v
Meaning here: Fraktur v denotes an arbitrary propositional valuation assigning a truth value to every sentence letter.
Conventional reading: A implies B
Meaning here: The complete propositional formula is read 'A implies B'. Spoken parentheses and connective names preserve its printed logical scope.
Conventional reading: B sub i equals A
Meaning here: The equation is read 'B sub i equals A'. It identifies the indexed derivation formula with the named final formula.
Conventional reading: the complete formula not not A is axiomatically derivable from premise set Gamma
Meaning here: The statement is read 'the complete formula not not A is axiomatically derivable from premise set Gamma'. It asserts or denies the existence of a finite axiomatic derivation with the displayed premise set and conclusion.
Conventional reading: open parenthesis D implies open parenthesis D implies D close parenthesis close parenthesis implies open parenthesis D implies D close parenthesis
Meaning here: The complete propositional formula is read 'open parenthesis D implies open parenthesis D implies D close parenthesis close parenthesis implies open parenthesis D implies D close parenthesis'. Spoken parentheses and connective names preserve its printed logical scope.
Conventional reading: A is syntactically identical to falsum
Meaning here: The expression is read 'A is syntactically identical to falsum'. It states syntactic identity of the two complete formulas, not merely semantic equivalence.
Conventional reading: B belongs to Gamma
Meaning here: The expression is read 'B belongs to Gamma'. This states that the displayed formula belongs to the displayed premise set.
Conventional reading: B belongs to Gamma union the set containing A
Meaning here: The expression is read 'B belongs to Gamma union the set containing A'. This states that the displayed formula belongs to the displayed premise set.
Conventional reading: not open parenthesis A or B close parenthesis implies not A
Meaning here: The complete propositional formula is read 'not open parenthesis A or B close parenthesis implies not A'. Spoken parentheses and connective names preserve its printed logical scope.
Conventional reading: open parenthesis open parenthesis A and B close parenthesis implies C close parenthesis implies open parenthesis A implies open parenthesis B implies C close parenthesis close parenthesis
Meaning here: The complete propositional formula is read 'open parenthesis open parenthesis A and B close parenthesis implies C close parenthesis implies open parenthesis A implies open parenthesis B implies C close parenthesis close parenthesis'. Spoken parentheses and connective names preserve its printed logical scope.
Conventional reading: the complete formula A implies C is axiomatically derivable from premise set Gamma
Meaning here: The statement is read 'the complete formula A implies C is axiomatically derivable from premise set Gamma'. It asserts or denies the existence of a finite axiomatic derivation with the displayed premise set and conclusion.
Conventional reading: the complete formula not B is axiomatically derivable from the union of Gamma and the singleton set containing not A
Meaning here: The statement is read 'the complete formula not B is axiomatically derivable from the union of Gamma and the singleton set containing not A'. It asserts or denies the existence of a finite axiomatic derivation with the displayed premise set and conclusion.
Conventional reading: the complete formula B is axiomatically derivable from the displayed premises the set containing A comma not A
Meaning here: The statement is read 'the complete formula B is axiomatically derivable from the displayed premises the set containing A comma not A'. It asserts or denies the existence of a finite axiomatic derivation with the displayed premise set and conclusion.
Conventional reading: derivation A sub one through A sub k, whose last formula is A; followed by derivation B sub one through B sub l, whose last formula is B
Meaning here: The displayed text concatenates a derivation ending in A with a derivation ending in B, preserving both indexed endpoints.
Conventional reading: D implies D
Meaning here: The complete propositional formula is read 'D implies D'. Spoken parentheses and connective names preserve its printed logical scope.
Conventional reading: valuation v does not satisfy falsum
Meaning here: The valuation statement is read 'valuation v does not satisfy falsum'. It states exactly whether v makes the complete displayed propositional formula true.
Conventional reading: B belongs to the set containing A
Meaning here: The expression is read 'B belongs to the set containing A'. This states that the displayed formula belongs to the displayed premise set.
Conventional reading: the complete formula falsum is not axiomatically derivable from premise set Gamma
Meaning here: The statement is read 'the complete formula falsum is not axiomatically derivable from premise set Gamma'. It asserts or denies the existence of a finite axiomatic derivation with the displayed premise set and conclusion.
Conventional reading: the complete formula B is axiomatically derivable from the union of the singleton set containing A and Delta
Meaning here: The statement is read 'the complete formula B is axiomatically derivable from the union of the singleton set containing A and Delta'. It asserts or denies the existence of a finite axiomatic derivation with the displayed premise set and conclusion.
Conventional reading: the complete formula A is axiomatically derivable from the union of Gamma and the singleton set containing B
Meaning here: The statement is read 'the complete formula A is axiomatically derivable from the union of Gamma and the singleton set containing B'. It asserts or denies the existence of a finite axiomatic derivation with the displayed premise set and conclusion.
Conventional reading: the complete formula not A implies falsum is axiomatically derivable from premise set Gamma
Meaning here: The statement is read 'the complete formula not A implies falsum is axiomatically derivable from premise set Gamma'. It asserts or denies the existence of a finite axiomatic derivation with the displayed premise set and conclusion.
Conventional reading: A sub i
Meaning here: A sub i names the derivation step whose correctness is being defined.
Conventional reading: Gamma
Meaning here: Gamma is the set of premise formulas from which axiomatic derivability is considered.
Conventional reading: axiomatic derivability
Meaning here: The turnstile denotes the axiomatic derivability relation defined by a finite derivation using axiom instances and modus ponens.
Conventional reading: the complete formula A implies B is axiomatically derivable from the union of Gamma and the singleton set containing A
Meaning here: The statement is read 'the complete formula A implies B is axiomatically derivable from the union of Gamma and the singleton set containing A'. It asserts or denies the existence of a finite axiomatic derivation with the displayed premise set and conclusion.
Conventional reading: Gamma is a subset of Delta
Meaning here: The expression is read 'Gamma is a subset of Delta'. This states inclusion between the two displayed premise sets.
Conventional reading: D implies open parenthesis B implies D close parenthesis
Meaning here: The complete propositional formula is read 'D implies open parenthesis B implies D close parenthesis'. Spoken parentheses and connective names preserve its printed logical scope.
Conventional reading: the complete formula open parenthesis A or B close parenthesis implies falsum is axiomatically derivable from the displayed premises the set containing not A comma not B
Meaning here: The statement is read 'the complete formula open parenthesis A or B close parenthesis implies falsum is axiomatically derivable from the displayed premises the set containing not A comma not B'. It asserts or denies the existence of a finite axiomatic derivation with the displayed premise set and conclusion.
Conventional reading: E
Meaning here: E is the arbitrary complete propositional formula used in this worked derivation.
Conventional reading: the complete formula B is axiomatically derivable from the union of premise sets Gamma and Delta
Meaning here: The statement is read 'the complete formula B is axiomatically derivable from the union of premise sets Gamma and Delta'. It asserts or denies the existence of a finite axiomatic derivation with the displayed premise set and conclusion.
Conventional reading: open parenthesis D implies open parenthesis open parenthesis D implies D close parenthesis implies D close parenthesis close parenthesis implies continued on the next display line
Meaning here: The complete propositional formula is read 'open parenthesis D implies open parenthesis open parenthesis D implies D close parenthesis implies D close parenthesis close parenthesis implies continued on the next display line'. Spoken parentheses and connective names preserve its printed logical scope.
Conventional reading: A sub i
Meaning here: A sub i is the formula at derivation step i.
Conventional reading: valuation v satisfies A
Meaning here: The valuation statement is read 'valuation v satisfies A'. It states exactly whether v makes the complete displayed propositional formula true.
Conventional reading: the complete formula B is axiomatically derivable from the displayed premises the set containing A comma A implies B
Meaning here: The statement is read 'the complete formula B is axiomatically derivable from the displayed premises the set containing A comma A implies B'. It asserts or denies the existence of a finite axiomatic derivation with the displayed premise set and conclusion.
Conventional reading: open parenthesis open parenthesis D implies open parenthesis D implies D close parenthesis close parenthesis implies open parenthesis D implies D close parenthesis close parenthesis
Meaning here: The complete propositional formula is read 'open parenthesis open parenthesis D implies open parenthesis D implies D close parenthesis close parenthesis implies open parenthesis D implies D close parenthesis close parenthesis'. Spoken parentheses and connective names preserve its printed logical scope.
Conventional reading: E implies open parenthesis D implies E close parenthesis
Meaning here: The complete propositional formula is read 'E implies open parenthesis D implies E close parenthesis'. Spoken parentheses and connective names preserve its printed logical scope.
Conventional reading: one
Meaning here: One is the exact derivation length or lower endpoint identified by each bound source packet.
Conventional reading: D implies open parenthesis D implies D close parenthesis
Meaning here: The complete propositional formula is read 'D implies open parenthesis D implies D close parenthesis'. Spoken parentheses and connective names preserve its printed logical scope.
Conventional reading: the complete formula not A is axiomatically derivable from premise set Gamma
Meaning here: The statement is read 'the complete formula not A is axiomatically derivable from premise set Gamma'. It asserts or denies the existence of a finite axiomatic derivation with the displayed premise set and conclusion.
Conventional reading: B sub i equals A
Meaning here: The equation is read 'B sub i equals A'. It identifies the indexed derivation formula with the named final formula.
Conventional reading: fourteen axiom schemes in source order. Conjunction elimination left: open parenthesis A and B close parenthesis implies A. Conjunction elimination right: open parenthesis A and B close parenthesis implies B. Conjunction introduction: A implies open parenthesis B implies open parenthesis A and B close parenthesis close parenthesis. Disjunction introduction left: A implies open parenthesis A or B close parenthesis. Disjunction introduction right: A implies open parenthesis B or A close parenthesis. Disjunction elimination: open parenthesis A implies C close parenthesis implies open parenthesis open parenthesis B implies C close parenthesis implies open parenthesis open parenthesis A or B close parenthesis implies C close parenthesis close parenthesis. Conditional scheme one: A implies open parenthesis B implies A close parenthesis. Conditional scheme two: open parenthesis A implies open parenthesis B implies C close parenthesis close parenthesis implies open parenthesis open parenthesis A implies B close parenthesis implies open parenthesis A implies C close parenthesis close parenthesis. Negation scheme one: open parenthesis A implies B close parenthesis implies open parenthesis open parenthesis A implies not B close parenthesis implies not A close parenthesis. Negation scheme two: not A implies open parenthesis A implies B close parenthesis. Truth scheme: verum. Falsity scheme one: falsum implies A. Falsity scheme two: open parenthesis A implies falsum close parenthesis implies not A. Double negation elimination: not not A implies A.
Meaning here: This is the complete ordered list of fourteen propositional axiom schemes, with every connective scope and source label preserved.
Conventional reading: A sub j
Meaning here: A sub j is an earlier formula used to justify step A sub i.
Conventional reading: from Gamma derive the conditional whose antecedent is the conditional from A to the conditional from C to B, and whose consequent is the conditional whose antecedent is the conditional from A to C and whose consequent is the conditional from A to B
Meaning here: The statement is read 'from Gamma derive the conditional whose antecedent is the conditional from A to the conditional from C to B, and whose consequent is the conditional whose antecedent is the conditional from A to C and whose consequent is the conditional from A to B'. It asserts or denies the existence of a finite axiomatic derivation with the displayed premise set and conclusion.
Conventional reading: the complete formula B is axiomatically derivable from the displayed premises A sub one comma through the omitted intermediate entries comma A sub n
Meaning here: The statement is read 'the complete formula B is axiomatically derivable from the displayed premises A sub one comma through the omitted intermediate entries comma A sub n'. It asserts or denies the existence of a finite axiomatic derivation with the displayed premise set and conclusion.
Conventional reading: the complete formula falsum is axiomatically derivable from the union of Gamma and the singleton set containing A
Meaning here: The statement is read 'the complete formula falsum is axiomatically derivable from the union of Gamma and the singleton set containing A'. It asserts or denies the existence of a finite axiomatic derivation with the displayed premise set and conclusion.
Conventional reading: the complete formula A implies B is axiomatically derivable from premise B
Meaning here: The statement is read 'the complete formula A implies B is axiomatically derivable from premise B'. It asserts or denies the existence of a finite axiomatic derivation with the displayed premise set and conclusion.
Conventional reading: the three formulas A or B, not A, and not B
Meaning here: The complete propositional formula is read 'the three formulas A or B, not A, and not B'. Spoken parentheses and connective names preserve its printed logical scope.
Conventional reading: the complete formula A implies B is axiomatically derivable from premise set Gamma
Meaning here: The statement is read 'the complete formula A implies B is axiomatically derivable from premise set Gamma'. It asserts or denies the existence of a finite axiomatic derivation with the displayed premise set and conclusion.
Conventional reading: A
Meaning here: A is the arbitrary complete propositional formula used in this exact source statement.
Conventional reading: the complete formula B is axiomatically derivable from the union of Gamma and the singleton set containing A
Meaning here: The statement is read 'the complete formula B is axiomatically derivable from the union of Gamma and the singleton set containing A'. It asserts or denies the existence of a finite axiomatic derivation with the displayed premise set and conclusion.
Conventional reading: the complete formula A or B is axiomatically derivable from premise B
Meaning here: The statement is read 'the complete formula A or B is axiomatically derivable from premise B'. It asserts or denies the existence of a finite axiomatic derivation with the displayed premise set and conclusion.
Conventional reading: A is syntactically identical to A sub n
Meaning here: The expression is read 'A is syntactically identical to A sub n'. It states syntactic identity of the two complete formulas, not merely semantic equivalence.
Conventional reading: B implies A
Meaning here: The complete propositional formula is read 'B implies A'. Spoken parentheses and connective names preserve its printed logical scope.
Conventional reading: the complete formula not B implies open parenthesis B implies falsum close parenthesis is derivable with no premises
Meaning here: The statement is read 'the complete formula not B implies open parenthesis B implies falsum close parenthesis is derivable with no premises'. It asserts or denies the existence of a finite axiomatic derivation with the displayed premise set and conclusion.
Conventional reading: open parenthesis not D implies open parenthesis D implies E close parenthesis close parenthesis implies open parenthesis open parenthesis E implies open parenthesis D implies E close parenthesis close parenthesis implies open parenthesis open parenthesis not D or E close parenthesis implies open parenthesis D implies E close parenthesis close parenthesis close parenthesis
Meaning here: The complete propositional formula is read 'open parenthesis not D implies open parenthesis D implies E close parenthesis close parenthesis implies open parenthesis open parenthesis E implies open parenthesis D implies E close parenthesis close parenthesis implies open parenthesis open parenthesis not D or E close parenthesis implies open parenthesis D implies E close parenthesis close parenthesis close parenthesis'. Spoken parentheses and connective names preserve its printed logical scope.
Conventional reading: the complete formula C is axiomatically derivable from the union of Gamma and the singleton set containing A
Meaning here: The statement is read 'the complete formula C is axiomatically derivable from the union of Gamma and the singleton set containing A'. It asserts or denies the existence of a finite axiomatic derivation with the displayed premise set and conclusion.
Conventional reading: open parenthesis D implies D close parenthesis
Meaning here: The complete propositional formula is read 'open parenthesis D implies D close parenthesis'. Spoken parentheses and connective names preserve its printed logical scope.
Conventional reading: the complete formula B implies falsum is axiomatically derivable from the premise set containing not B
Meaning here: The statement is read 'the complete formula B implies falsum is axiomatically derivable from the premise set containing not B'. It asserts or denies the existence of a finite axiomatic derivation with the displayed premise set and conclusion.
Conventional reading: the set containing A union Delta
Meaning here: The expression is read 'the set containing A union Delta'. This forms the union of the displayed premise sets.
Conventional reading: the complete formula A sub i is axiomatically derivable from premise set Gamma
Meaning here: The statement is read 'the complete formula A sub i is axiomatically derivable from premise set Gamma'. It asserts or denies the existence of a finite axiomatic derivation with the displayed premise set and conclusion.
Conventional reading: open parenthesis not D implies open parenthesis D implies E close parenthesis close parenthesis implies continued on the next display line
Meaning here: The complete propositional formula is read 'open parenthesis not D implies open parenthesis D implies E close parenthesis close parenthesis implies continued on the next display line'. Spoken parentheses and connective names preserve its printed logical scope.
Conventional reading: the complete formula B is axiomatically derivable from the displayed premises A comma A implies B
Meaning here: The statement is read 'the complete formula B is axiomatically derivable from the displayed premises A comma A implies B'. It asserts or denies the existence of a finite axiomatic derivation with the displayed premise set and conclusion.
Conventional reading: the complete formula B is semantically entailed by premise set Gamma
Meaning here: The statement is read 'the complete formula B is semantically entailed by premise set Gamma'. Every propositional valuation satisfying every formula in Gamma also satisfies the complete displayed conclusion.
Conventional reading: A implies A
Meaning here: The complete propositional formula is read 'A implies A'. Spoken parentheses and connective names preserve its printed logical scope.
Conventional reading: not D
Meaning here: The complete propositional formula is read 'not D'. Spoken parentheses and connective names preserve its printed logical scope.
Conventional reading: the complete formula not A implies open parenthesis A implies falsum close parenthesis is axiomatically derivable from premise set Gamma
Meaning here: The statement is read 'the complete formula not A implies open parenthesis A implies falsum close parenthesis is axiomatically derivable from premise set Gamma'. It asserts or denies the existence of a finite axiomatic derivation with the displayed premise set and conclusion.
Conventional reading: the complete formula not A is axiomatically derivable from the union of Gamma and the singleton set containing not A
Meaning here: The statement is read 'the complete formula not A is axiomatically derivable from the union of Gamma and the singleton set containing not A'. It asserts or denies the existence of a finite axiomatic derivation with the displayed premise set and conclusion.
Conventional reading: C
Meaning here: C is the arbitrary complete propositional formula used in this exact source statement.
Conventional reading: not A belongs to Gamma
Meaning here: The expression is read 'not A belongs to Gamma'. This states that the displayed formula belongs to the displayed premise set.
Conventional reading: Gamma union the set containing not A
Meaning here: The expression is read 'Gamma union the set containing not A'. This forms the union of the displayed premise sets.
Conventional reading: D implies E
Meaning here: The complete propositional formula is read 'D implies E'. Spoken parentheses and connective names preserve its printed logical scope.
Conventional reading: A sub i belongs to Gamma
Meaning here: The expression is read 'A sub i belongs to Gamma'. This states that the displayed formula belongs to the displayed premise set.
Conventional reading: the complete formula not not A implies A is axiomatically derivable from premise set Gamma
Meaning here: The statement is read 'the complete formula not not A implies A is axiomatically derivable from premise set Gamma'. It asserts or denies the existence of a finite axiomatic derivation with the displayed premise set and conclusion.
Conventional reading: Gamma sub zero is a subset of Gamma
Meaning here: The expression is read 'Gamma sub zero is a subset of Gamma'. This states inclusion between the two displayed premise sets.
Conventional reading: A implies C
Meaning here: The complete propositional formula is read 'A implies C'. Spoken parentheses and connective names preserve its printed logical scope.
Conventional reading: open parenthesis B implies C close parenthesis implies open parenthesis A implies open parenthesis B implies C close parenthesis close parenthesis
Meaning here: The complete propositional formula is read 'open parenthesis B implies C close parenthesis implies open parenthesis A implies open parenthesis B implies C close parenthesis close parenthesis'. Spoken parentheses and connective names preserve its printed logical scope.
Conventional reading: the complete formula B is axiomatically derivable from premise set Gamma
Meaning here: The statement is read 'the complete formula B is axiomatically derivable from premise set Gamma'. It asserts or denies the existence of a finite axiomatic derivation with the displayed premise set and conclusion.
Conventional reading: open parenthesis A implies open parenthesis B implies C close parenthesis close parenthesis implies open parenthesis open parenthesis A implies B close parenthesis implies open parenthesis A implies C close parenthesis close parenthesis
Meaning here: The complete propositional formula is read 'open parenthesis A implies open parenthesis B implies C close parenthesis close parenthesis implies open parenthesis open parenthesis A implies B close parenthesis implies open parenthesis A implies C close parenthesis close parenthesis'. Spoken parentheses and connective names preserve its printed logical scope.
Conventional reading: the complete formula A is axiomatically derivable from the union of Gamma and the singleton set containing not A
Meaning here: The statement is read 'the complete formula A is axiomatically derivable from the union of Gamma and the singleton set containing not A'. It asserts or denies the existence of a finite axiomatic derivation with the displayed premise set and conclusion.
Conventional reading: the complete formula A is semantically entailed by premise set Gamma
Meaning here: The statement is read 'the complete formula A is semantically entailed by premise set Gamma'. Every propositional valuation satisfying every formula in Gamma also satisfies the complete displayed conclusion.
Conventional reading: D implies open parenthesis open parenthesis D implies D close parenthesis implies D close parenthesis
Meaning here: The complete propositional formula is read 'D implies open parenthesis open parenthesis D implies D close parenthesis implies D close parenthesis'. Spoken parentheses and connective names preserve its printed logical scope.
Conventional reading: open parenthesis open parenthesis A implies B close parenthesis implies open parenthesis A implies C close parenthesis close parenthesis
Meaning here: The complete propositional formula is read 'open parenthesis open parenthesis A implies B close parenthesis implies open parenthesis A implies C close parenthesis close parenthesis'. Spoken parentheses and connective names preserve its printed logical scope.
Conventional reading: biconditional connective
Meaning here: The term 'biconditional connective' names the displayed propositional connective.
Conventional reading: the complete formula A and B is axiomatically derivable from the displayed premises A comma B
Meaning here: The statement is read 'the complete formula A and B is axiomatically derivable from the displayed premises A comma B'. It asserts or denies the existence of a finite axiomatic derivation with the displayed premise set and conclusion.
Conventional reading: the complete formula A implies falsum is axiomatically derivable from the premise set containing not A
Meaning here: The statement is read 'the complete formula A implies falsum is axiomatically derivable from the premise set containing not A'. It asserts or denies the existence of a finite axiomatic derivation with the displayed premise set and conclusion.
Conventional reading: the complete formula C implies B is axiomatically derivable from the union of Gamma and the singleton set containing A
Meaning here: The statement is read 'the complete formula C implies B is axiomatically derivable from the union of Gamma and the singleton set containing A'. It asserts or denies the existence of a finite axiomatic derivation with the displayed premise set and conclusion.
Conventional reading: C implies B
Meaning here: The complete propositional formula is read 'C implies B'. Spoken parentheses and connective names preserve its printed logical scope.
Conventional reading: the complete formula A is axiomatically derivable from the union of Gamma and the singleton set containing B
Meaning here: The statement is read 'the complete formula A is axiomatically derivable from the union of Gamma and the singleton set containing B'. It asserts or denies the existence of a finite axiomatic derivation with the displayed premise set and conclusion.
The source form is preserved; the reader projection is separately disclosed.
Conventional reading: B belongs to Gamma union the set containing A
Meaning here: The expression is read 'B belongs to Gamma union the set containing A'. This states that the displayed formula belongs to the displayed premise set.
Conventional reading: A belongs to Gamma
Meaning here: The expression is read 'A belongs to Gamma'. This states that the displayed formula belongs to the displayed premise set.
Conventional reading: open parenthesis A implies open parenthesis B implies C close parenthesis close parenthesis implies continued on the next display line
Meaning here: The complete propositional formula is read 'open parenthesis A implies open parenthesis B implies C close parenthesis close parenthesis implies continued on the next display line'. Spoken parentheses and connective names preserve its printed logical scope.
Conventional reading: the complete formula B implies open parenthesis A implies B close parenthesis is axiomatically derivable from premise set Gamma
Meaning here: The statement is read 'the complete formula B implies open parenthesis A implies B close parenthesis is axiomatically derivable from premise set Gamma'. It asserts or denies the existence of a finite axiomatic derivation with the displayed premise set and conclusion.
Conventional reading: the complete formula falsum is axiomatically derivable from the union of Gamma and the singleton set containing not A
Meaning here: The statement is read 'the complete formula falsum is axiomatically derivable from the union of Gamma and the singleton set containing not A'. It asserts or denies the existence of a finite axiomatic derivation with the displayed premise set and conclusion.
Conventional reading: the complete formula A is not derivable with no premises
Meaning here: The statement is read 'the complete formula A is not derivable with no premises'. It asserts or denies the existence of a finite axiomatic derivation with the displayed premise set and conclusion.
Conventional reading: the complete formula A is derivable with no premises
Meaning here: The statement is read 'the complete formula A is derivable with no premises'. It asserts or denies the existence of a finite axiomatic derivation with the displayed premise set and conclusion.
Conventional reading: the complete formula A is axiomatically derivable from the union of Gamma and the singleton set containing A
Meaning here: The statement is read 'the complete formula A is axiomatically derivable from the union of Gamma and the singleton set containing A'. It asserts or denies the existence of a finite axiomatic derivation with the displayed premise set and conclusion.
Conventional reading: the complete formula A implies B is axiomatically derivable from premise not A
Meaning here: The statement is read 'the complete formula A implies B is axiomatically derivable from premise not A'. It asserts or denies the existence of a finite axiomatic derivation with the displayed premise set and conclusion.
Conventional reading: the complete formula A is axiomatically derivable from premise set Gamma
Meaning here: The statement is read 'the complete formula A is axiomatically derivable from premise set Gamma'. It asserts or denies the existence of a finite axiomatic derivation with the displayed premise set and conclusion.
Conventional reading: the complete formula A is axiomatically derivable from premise set Gamma sub zero
Meaning here: The statement is read 'the complete formula A is axiomatically derivable from premise set Gamma sub zero'. It asserts or denies the existence of a finite axiomatic derivation with the displayed premise set and conclusion.
Conventional reading: falsum
Meaning here: Falsum is the always-false propositional constant used to define inconsistency and negation.
Conventional reading: the complete formula A is axiomatically derivable from premise A and B
Meaning here: The statement is read 'the complete formula A is axiomatically derivable from premise A and B'. It asserts or denies the existence of a finite axiomatic derivation with the displayed premise set and conclusion.
Conventional reading: Gamma sub zero
Meaning here: Gamma sub zero is the finite subset of Gamma selected by compactness.
Conventional reading: conditional connective
Meaning here: The term 'conditional connective' names the displayed propositional connective.
Conventional reading: B
Meaning here: B is the arbitrary complete propositional formula used in this exact source statement.
Conventional reading: the complete formula not not A is axiomatically derivable from premise set Gamma
Meaning here: The statement is read 'the complete formula not not A is axiomatically derivable from premise set Gamma'. It asserts or denies the existence of a finite axiomatic derivation with the displayed premise set and conclusion.
Conventional reading: A implies open parenthesis B implies C close parenthesis
Meaning here: The complete propositional formula is read 'A implies open parenthesis B implies C close parenthesis'. Spoken parentheses and connective names preserve its printed logical scope.
Conventional reading: the complete formula A is axiomatically derivable from premise set Delta
Meaning here: The statement is read 'the complete formula A is axiomatically derivable from premise set Delta'. It asserts or denies the existence of a finite axiomatic derivation with the displayed premise set and conclusion.
Conventional reading: the complete formula A or B is axiomatically derivable from premise A
Meaning here: The statement is read 'the complete formula A or B is axiomatically derivable from premise A'. It asserts or denies the existence of a finite axiomatic derivation with the displayed premise set and conclusion.
Conventional reading: the complete formula B implies C is axiomatically derivable from premise set Gamma
Meaning here: The statement is read 'the complete formula B implies C is axiomatically derivable from premise set Gamma'. It asserts or denies the existence of a finite axiomatic derivation with the displayed premise set and conclusion.
Conventional reading: B implies C
Meaning here: The complete propositional formula is read 'B implies C'. Spoken parentheses and connective names preserve its printed logical scope.
Conventional reading: open parenthesis not D or E close parenthesis implies open parenthesis D implies E close parenthesis
Meaning here: The complete propositional formula is read 'open parenthesis not D or E close parenthesis implies open parenthesis D implies E close parenthesis'. Spoken parentheses and connective names preserve its printed logical scope.
Conventional reading: not D implies open parenthesis D implies E close parenthesis
Meaning here: The complete propositional formula is read 'not D implies open parenthesis D implies E close parenthesis'. Spoken parentheses and connective names preserve its printed logical scope.
Conventional reading: i is less than or equal to n
Meaning here: The condition i is less than or equal to n ranges the current step index i over the positions one through n in the finite derivation.
Conventional reading: k is less than i
Meaning here: The index condition is read 'k is less than i'. It requires every cited justification step to occur earlier than the step it supports, within the finite range ending at n.
Conventional reading: A sub n
Meaning here: A sub n is the last formula of the finite derivation under discussion.
Conventional reading: i
Meaning here: i is the index ranging over the displayed finite family of formulas.
Conventional reading: A sub one
Meaning here: A sub one is the first formula of the finite axiomatic derivation.
Conventional reading: open parenthesis open parenthesis E implies open parenthesis D implies E close parenthesis close parenthesis implies open parenthesis open parenthesis not D or E close parenthesis implies open parenthesis D implies E close parenthesis close parenthesis close parenthesis
Meaning here: The complete propositional formula is read 'open parenthesis open parenthesis E implies open parenthesis D implies E close parenthesis close parenthesis implies open parenthesis open parenthesis not D or E close parenthesis implies open parenthesis D implies E close parenthesis close parenthesis close parenthesis'. Spoken parentheses and connective names preserve its printed logical scope.
Conventional reading: B is syntactically identical to A
Meaning here: The expression is read 'B is syntactically identical to A'. It states syntactic identity of the two complete formulas, not merely semantic equivalence.
Conventional reading: Gamma union the set containing A
Meaning here: The expression is read 'Gamma union the set containing A'. This forms the union of the displayed premise sets.
Conventional reading: A sub k equals A
Meaning here: The equation is read 'A sub k equals A'. It identifies the indexed derivation formula with the named final formula.
Conventional reading: j is less than i
Meaning here: The index condition is read 'j is less than i'. It requires every cited justification step to occur earlier than the step it supports, within the finite range ending at n.
Conventional reading: language L
Meaning here: Calligraphic L denotes the propositional language whose formulas occur in these derivations.
Conventional reading: Delta
Meaning here: Delta is the comparison set of premise formulas in monotonicity or transitivity.
Conventional reading: the complete formula B is axiomatically derivable from premise A and B
Meaning here: The statement is read 'the complete formula B is axiomatically derivable from premise A and B'. It asserts or denies the existence of a finite axiomatic derivation with the displayed premise set and conclusion.
Conventional reading: open parenthesis A and B close parenthesis implies open parenthesis B and A close parenthesis
Meaning here: The complete propositional formula is read 'open parenthesis A and B close parenthesis implies open parenthesis B and A close parenthesis'. Spoken parentheses and connective names preserve its printed logical scope.
Conventional reading: D
Meaning here: D is the arbitrary complete propositional formula used in this worked derivation.
Conventional reading: the complete formula B implies A is semantically entailed by premise set Gamma
Meaning here: The statement is read 'the complete formula B implies A is semantically entailed by premise set Gamma'. Every propositional valuation satisfying every formula in Gamma also satisfies the complete displayed conclusion.
Conventional reading: the complete formula falsum is axiomatically derivable from the displayed premises the set containing A or B comma not A comma not B
Meaning here: The statement is read 'the complete formula falsum is axiomatically derivable from the displayed premises the set containing A or B comma not A comma not B'. It asserts or denies the existence of a finite axiomatic derivation with the displayed premise set and conclusion.
Conventional reading: Gamma union Delta
Meaning here: The expression is read 'Gamma union Delta'. This forms the union of the displayed premise sets.
Conventional reading: B sub one
Meaning here: B sub one is the first formula in the cited derivation of B.
Conventional reading: two statements: from Gamma derive the conditional from A to the conditional from C to B; and from Gamma derive the conditional from A to C
Meaning here: The statement is read 'two statements: from Gamma derive the conditional from A to the conditional from C to B; and from Gamma derive the conditional from A to C'. It asserts or denies the existence of a finite axiomatic derivation with the displayed premise set and conclusion.
The derivation uses three named propositional axiom schemes and two applications of modus ponens. A long formula on line two is split across two printed rows and is preserved as two ordered source segments.
Words-only linearization: Five-line derivation from not D or E to D implies E. The derivation uses three named propositional axiom schemes and two applications of modus ponens. A long formula on line two is split across two printed rows and is preserved as two ordered source segments. Line one: not D implies open parenthesis D implies E close parenthesis. Justification: the second negation axiom scheme. Line two is printed in two formula segments. Segment one: open parenthesis not D implies open parenthesis D implies E close parenthesis close parenthesis implies continued on the next display line. Segment two: open parenthesis open parenthesis E implies open parenthesis D implies E close parenthesis close parenthesis implies open parenthesis open parenthesis not D or E close parenthesis implies open parenthesis D implies E close parenthesis close parenthesis close parenthesis. Justification: the third disjunction axiom scheme. Line three: open parenthesis E implies open parenthesis D implies E close parenthesis close parenthesis implies open parenthesis open parenthesis not D or E close parenthesis implies open parenthesis D implies E close parenthesis close parenthesis. Justification: modus ponens from lines one and two. Line four: E implies open parenthesis D implies E close parenthesis. Justification: the first conditional axiom scheme. Line five: open parenthesis not D or E close parenthesis implies open parenthesis D implies E close parenthesis. Justification: modus ponens from lines three and four. Resolved reference one: Reference to the second negation axiom scheme. Resolved reference two: Reference to the third disjunction axiom scheme. Resolved reference three: Reference to the first conditional axiom scheme.
The derivation uses three conditional-axiom instances and two applications of modus ponens. Its second line is preserved as two ordered printed formula segments.
Words-only linearization: Five-line derivation of D implies D. The derivation uses three conditional-axiom instances and two applications of modus ponens. Its second line is preserved as two ordered printed formula segments. Line one: D implies open parenthesis open parenthesis D implies D close parenthesis implies D close parenthesis. Justification: the first conditional axiom scheme. Line two is printed in two formula segments. Segment one: open parenthesis D implies open parenthesis open parenthesis D implies D close parenthesis implies D close parenthesis close parenthesis implies continued on the next display line. Segment two: open parenthesis open parenthesis D implies open parenthesis D implies D close parenthesis close parenthesis implies open parenthesis D implies D close parenthesis close parenthesis. Justification: the second conditional axiom scheme. Line three: open parenthesis D implies open parenthesis D implies D close parenthesis close parenthesis implies open parenthesis D implies D close parenthesis. Justification: modus ponens from lines one and two. Line four: D implies open parenthesis D implies D close parenthesis. Justification: the first conditional axiom scheme. Line five: D implies D. Justification: modus ponens from lines three and four. Resolved reference one: Reference to the first conditional axiom scheme. Resolved reference two: Reference to the second conditional axiom scheme. Resolved reference three: Reference to the first conditional axiom scheme.
The seven-line derivation begins with two hypotheses, adds instances of the two conditional axiom schemes, and applies modus ponens three times. Its fifth line spans two printed formula segments.
Words-only linearization: Seven-line derivation chaining A implies B and B implies C. The seven-line derivation begins with two hypotheses, adds instances of the two conditional axiom schemes, and applies modus ponens three times. Its fifth line spans two printed formula segments. Line one: A implies B. Justification: hypothesis. Line two: B implies C. Justification: hypothesis. Line three: open parenthesis B implies C close parenthesis implies open parenthesis A implies open parenthesis B implies C close parenthesis close parenthesis. Justification: the first conditional axiom scheme. Line four: A implies open parenthesis B implies C close parenthesis. Justification: modus ponens from lines two and three. Line five is printed in two formula segments. Segment one: open parenthesis A implies open parenthesis B implies C close parenthesis close parenthesis implies continued on the next display line. Segment two: open parenthesis open parenthesis A implies B close parenthesis implies open parenthesis A implies C close parenthesis close parenthesis. Justification: the second conditional axiom scheme. Line six: open parenthesis open parenthesis A implies B close parenthesis implies open parenthesis A implies C close parenthesis close parenthesis. Justification: modus ponens from lines four and five. Line seven: A implies C. Justification: modus ponens from lines one and six. Resolved reference one: Reference to the first conditional axiom scheme. Resolved reference two: Reference to the second conditional axiom scheme.
The derivation takes A and the conditional from A to B as hypotheses, then obtains B by modus ponens.
Words-only linearization: Three-line derivation by modus ponens. The derivation takes A and the conditional from A to B as hypotheses, then obtains B by modus ponens. Line one: A. Justification: hypothesis. Line two: A implies B. Justification: hypothesis. Line three: B. Justification: modus ponens from lines one and two.
The derivation takes A and the conditional from A to B as hypotheses and obtains B by modus ponens.
Words-only linearization: Three-line conditional-elimination derivation. The derivation takes A and the conditional from A to B as hypotheses and obtains B by modus ponens. Line one: A. Justification: hypothesis. Line two: A implies B. Justification: hypothesis. Line three: B. Justification: modus ponens from lines one and two.