From 610ac0e2ef212636ce5dabd108c3ba2e2b14fc49 Mon Sep 17 00:00:00 2001 From: Landon D. C. Elkind Date: Wed, 3 Feb 2021 16:05:11 -0700 Subject: Delete No1.v --- No1.v | 30 ------------------------------ 1 file changed, 30 deletions(-) delete mode 100644 No1.v diff --git a/No1.v b/No1.v deleted file mode 100644 index 6652c03..0000000 --- a/No1.v +++ /dev/null @@ -1,30 +0,0 @@ -Require Import Unicode.Utf8. - -Module No1. - -Import Unicode.Utf8. (*We first give the axioms of Principia for the propositional calculus in *1.*) - -Axiom MP1_1 : ∀ P Q : Prop, - (P → Q) → P → Q. (*Modus ponens*) - - (**1.11 ommitted: it is MP for propositions containing variables. Likewise, ommitted the well-formedness rules 1.7, 1.71, 1.72*) - -Axiom Taut1_2 : ∀ P : Prop, - P ∨ P→ P. (*Tautology*) - -Axiom Add1_3 : ∀ P Q : Prop, - Q → P ∨ Q. (*Addition*) - -Axiom Perm1_4 : ∀ P Q : Prop, - P ∨ Q → Q ∨ P. (*Permutation*) - -Axiom Assoc1_5 : ∀ P Q R : Prop, - P ∨ (Q ∨ R) → Q ∨ (P ∨ R). - -Axiom Sum1_6: ∀ P Q R : Prop, - (Q → R) → (P ∨ Q → P ∨ R). (*These are all the propositional axioms of Principia Mathematica.*) - -Axiom Impl1_01 : ∀ P Q : Prop, - (P → Q) = (~P ∨ Q). (*This is a definition in Principia: there → is a defined sign and ∨, ~ are primitive ones. So we will use this axiom to switch between disjunction and implication.*) - -End No1. \ No newline at end of file -- cgit v1.2.3