Hackstaff calls this system P+ (P sub plus), not to be confused with Church's P+
[Hilbert and Bernays, 1934, p68-71, plus table on p66]
[Hilbert und Ackermann, 1959, p39]
Note that this is (by inspection), the system ICI plus the Hilbert Axioms (above) for the individual operators other than implication. (Hackstaff specificly acknowledges the axioms from Hilbert) -JH
PPL + appropriate axioms for NOT gives standard PC. [Hackstaff, 1966, p95]
PPL + appropriate axioms for NOT gives Intuitionist PC. [Hackstaff, 1966, p223]
PPL + appropriate axioms for NOT gives Fitch Calculus. [Hackstaff, 1966, p223]
PPL + appropriate axioms for NOT gives Johansson Minimal Calculus [Hackstaff, 1966, p229]
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This page was last modified on August 11th, 2006