diff options
Diffstat (limited to 'PL.v')
| -rw-r--r-- | PL.v | 246 |
1 files changed, 151 insertions, 95 deletions
@@ -1,39 +1,95 @@ Require Import Unicode.Utf8. +Require Import Classical_Prop. +Require Import ClassicalFacts. +Require Import PropExtensionality. Module No1. Import Unicode.Utf8. +Import ClassicalFacts. +Import Classical_Prop. +Import PropExtensionality. + (*We first give the axioms of Principia for the propositional calculus in *1.*) -Axiom Impl1_01 : ∀ P Q : Prop, - (P → Q) = (¬P ∨ Q). +Theorem Impl1_01 : ∀ P Q : Prop, + (P → Q) = (¬P ∨ Q). +Proof. intros P Q. + apply propositional_extensionality. + split. + apply imply_to_or. + apply or_to_imply. +Qed. (*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.*) -Axiom MP1_1 : ∀ P Q : Prop, +Theorem MP1_1 : ∀ P Q : Prop, (P → Q) → P → Q. (*Modus ponens*) - +Proof. intros P Q. + intros iff_refl. + apply iff_refl. +Qed. (*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, +Theorem Taut1_2 : ∀ P : Prop, P ∨ P → P. (*Tautology*) +Proof. intros P. + apply imply_and_or. + apply iff_refl. +Qed. -Axiom Add1_3 : ∀ P Q : Prop, +Theorem Add1_3 : ∀ P Q : Prop, Q → P ∨ Q. (*Addition*) +Proof. intros P Q. + apply or_intror. +Qed. -Axiom Perm1_4 : ∀ P Q : Prop, +Theorem Perm1_4 : ∀ P Q : Prop, P ∨ Q → Q ∨ P. (*Permutation*) +Proof. intros P Q. + apply or_comm. +Qed. -Axiom Assoc1_5 : ∀ P Q R : Prop, +Theorem Assoc1_5 : ∀ P Q R : Prop, P ∨ (Q ∨ R) → Q ∨ (P ∨ R). (*Association*) +Proof. intros P Q R. + specialize or_assoc with P Q R. + intros or_assoc1. + replace (P∨Q∨R) with ((P∨Q)∨R). + specialize or_comm with P Q. + intros or_comm1. + replace (P∨Q) with (Q∨P). + specialize or_assoc with Q P R. + intros or_assoc2. + replace ((Q∨P)∨R) with (Q∨P∨R). + apply iff_refl. + apply propositional_extensionality. + apply iff_sym. + apply or_assoc2. + apply propositional_extensionality. + apply or_comm. + apply propositional_extensionality. + apply or_assoc. +Qed. -Axiom Sum1_6: ∀ P Q R : Prop, +Theorem Sum1_6 : ∀ P Q R : Prop, (Q → R) → (P ∨ Q → P ∨ R). (*Summation*) - +Proof. intros P Q R. + specialize imply_and_or2 with Q R P. + intros imply_and_or2a. + replace (P∨Q) with (Q∨P). + replace (P∨R) with (R∨P). + apply imply_and_or2a. + apply propositional_extensionality. + apply or_comm. + apply propositional_extensionality. + apply or_comm. +Qed. + (*These are all the propositional axioms of Principia.*) End No1. @@ -637,7 +693,7 @@ Proof. intros P Q. MP Syll2_06a Perm1_4a. Syll n2_55a Syll2_06a Sa. apply Sa. - Qed. +Qed. Theorem n2_6 : ∀ P Q : Prop, (¬P→Q) → ((P → Q) → Q). @@ -1547,7 +1603,7 @@ Theorem n4_12 : ∀ P Q : Prop, rewrite <- Equiv4_01 in H. rewrite <- Equiv4_01 in H. apply H. - Qed. +Qed. Theorem n4_13 : ∀ P : Prop, P ↔ ¬¬P. @@ -1563,7 +1619,7 @@ Theorem n4_13 : ∀ P : Prop, Equiv H. apply H. apply Equiv4_01. - Qed. +Qed. Theorem n4_14 : ∀ P Q R : Prop, ((P ∧ Q) → R) ↔ ((P ∧ ¬R) → ¬Q). @@ -1631,7 +1687,7 @@ Theorem n4_15 : ∀ P Q R : Prop, apply Equiv4_01. apply EqBi. apply n4_13a. - Qed. +Qed. Theorem n4_2 : ∀ P : Prop, P ↔ P. @@ -1645,7 +1701,7 @@ Theorem n4_2 : ∀ P : Prop, Equiv n3_2a. apply n3_2a. apply Equiv4_01. - Qed. +Qed. Theorem n4_21 : ∀ P Q : Prop, (P ↔ Q) ↔ (Q ↔ P). @@ -1789,9 +1845,9 @@ Theorem n4_31 : ∀ P Q : Prop, apply Equiv4_01. Qed. - Theorem n4_32 : ∀ P Q R : Prop, +Theorem n4_32 : ∀ P Q R : Prop, ((P ∧ Q) ∧ R) ↔ (P ∧ (Q ∧ R)). - Proof. intros P Q R. + Proof. intros P Q R. specialize n4_15 with P Q R. intros n4_15a. specialize Transp4_1 with P (¬(Q ∧ R)). @@ -1828,7 +1884,7 @@ Qed. specialize n4_13 with (Q ∧ R). intros n4_13a. apply n4_13a. - Qed. +Qed. (*Note that the actual proof uses n4_12, but that transposition involves transforming a biconditional into a conditional. This theorem @@ -1850,10 +1906,10 @@ Theorem n4_33 : ∀ P Q R : Prop, Equiv H. apply H. apply Equiv4_01. - Qed. +Qed. Axiom Abb4_34 : ∀ P Q R : Prop, - P ∧ Q ∧ R = ((P ∧ Q) ∧ R). + (P ∧ Q ∧ R) = ((P ∧ Q) ∧ R). (*This axiom ensures left association of brackets. Coq's default is right association. But Principia proves associativity of logical product as n4_32. @@ -1882,7 +1938,7 @@ Proof. intros P Q R. apply n3_47a. apply Equiv4_01. apply Equiv4_01. - Qed. +Qed. Theorem n4_37 : ∀ P Q R : Prop, (P ↔ Q) → ((P ∨ R) ↔ (Q ∨ R)). @@ -1915,7 +1971,7 @@ Proof. intros P Q R. apply n4_31b. apply Equiv4_01. apply Equiv4_01. - Qed. +Qed. Theorem n4_38 : ∀ P Q R S : Prop, ((P ↔ R) ∧ (Q ↔ S)) → ((P ∧ Q) ↔ (R ∧ S)). @@ -1986,7 +2042,7 @@ Proof. intros P Q R S. reflexivity. apply EqBi. apply n4_32a. - Qed. +Qed. Theorem n4_39 : ∀ P Q R S : Prop, ((P ↔ R) ∧ (Q ↔ S)) → ((P ∨ Q) ↔ (R ∨ S)). @@ -2057,7 +2113,7 @@ Proof. intros P Q R S. apply EqBi. apply n4_32a. apply Equiv4_01. - Qed. +Qed. Theorem n4_4 : ∀ P Q R : Prop, (P ∧ (Q ∨ R)) ↔ ((P∧ Q) ∨ (P ∧ R)). @@ -2266,7 +2322,7 @@ Theorem n4_44 : ∀ P Q : Prop, Equiv H. apply H. apply Equiv4_01. - Qed. +Qed. Theorem n4_45 : ∀ P Q : Prop, P ↔ (P ∧ (P ∨ Q)). @@ -2303,7 +2359,7 @@ Theorem n4_5 : ∀ P Q : Prop, replace (¬(¬P ∨ ¬Q)) with (P ∧ Q). apply n4_2a. apply Prod3_01. - Qed. +Qed. Theorem n4_51 : ∀ P Q : Prop, ¬(P ∧ Q) ↔ (¬P ∨ ¬Q). @@ -2327,7 +2383,7 @@ Theorem n4_51 : ∀ P Q : Prop, apply n4_21b. apply EqBi. apply EqBi. - Qed. +Qed. Theorem n4_52 : ∀ P Q : Prop, (P ∧ ¬Q) ↔ ¬(¬P ∨ Q). @@ -2340,7 +2396,7 @@ Theorem n4_52 : ∀ P Q : Prop, intros n4_13a. apply EqBi. apply n4_13a. - Qed. +Qed. Theorem n4_53 : ∀ P Q : Prop, ¬(P ∧ ¬Q) ↔ (¬P ∨ Q). @@ -2362,7 +2418,7 @@ Theorem n4_53 : ∀ P Q : Prop, apply n4_21a. apply EqBi. apply EqBi. - Qed. +Qed. Theorem n4_54 : ∀ P Q : Prop, (¬P ∧ Q) ↔ ¬(P ∨ ¬Q). @@ -2375,7 +2431,7 @@ Theorem n4_54 : ∀ P Q : Prop, apply n4_5a. apply EqBi. apply n4_13a. - Qed. +Qed. Theorem n4_55 : ∀ P Q : Prop, ¬(¬P ∧ Q) ↔ (P ∨ ¬Q). @@ -2402,7 +2458,7 @@ Theorem n4_55 : ∀ P Q : Prop, (¬P∧Q↔¬(P∨¬Q)). intros n4_21b. apply n4_21. - Qed. +Qed. Theorem n4_56 : ∀ P Q : Prop, (¬P ∧ ¬Q) ↔ ¬(P ∨ Q). @@ -2415,7 +2471,7 @@ Theorem n4_56 : ∀ P Q : Prop, specialize n4_13 with Q. intros n4_13a. apply n4_13a. - Qed. +Qed. Theorem n4_57 : ∀ P Q : Prop, ¬(¬P ∧ ¬Q) ↔ (P ∨ Q). @@ -2442,7 +2498,7 @@ Theorem n4_57 : ∀ P Q : Prop, (P ∨ Q ↔ ¬(¬P ∧ ¬Q)) (¬P ∧ ¬Q ↔ ¬(P ∨ Q)). intros n4_21b. apply n4_21b. - Qed. +Qed. Theorem n4_6 : ∀ P Q : Prop, (P → Q) ↔ (¬P ∨ Q). @@ -2451,7 +2507,7 @@ Theorem n4_6 : ∀ P Q : Prop, intros n4_2a. rewrite Impl1_01. apply n4_2a. - Qed. +Qed. Theorem n4_61 : ∀ P Q : Prop, ¬(P → Q) ↔ (P ∧ ¬Q). @@ -2477,7 +2533,7 @@ Theorem n4_61 : ∀ P Q : Prop, ((P→Q)↔(¬P∨Q)). intros n4_21a. apply n4_21a. - Qed. +Qed. Theorem n4_62 : ∀ P Q : Prop, (P → ¬Q) ↔ (¬P ∨ ¬Q). @@ -2485,7 +2541,7 @@ Theorem n4_62 : ∀ P Q : Prop, specialize n4_6 with P (¬Q). intros n4_6a. apply n4_6a. - Qed. +Qed. Theorem n4_63 : ∀ P Q : Prop, ¬(P → ¬Q) ↔ (P ∧ Q). @@ -2511,7 +2567,7 @@ Theorem n4_63 : ∀ P Q : Prop, apply n4_21a. apply EqBi. apply n4_5a. - Qed. +Qed. Theorem n4_64 : ∀ P Q : Prop, (¬P → Q) ↔ (P ∨ Q). @@ -2527,7 +2583,7 @@ Theorem n4_64 : ∀ P Q : Prop, Equiv H. apply H. apply Equiv4_01. - Qed. +Qed. Theorem n4_65 : ∀ P Q : Prop, ¬(¬P → Q) ↔ (¬P ∧ ¬Q). @@ -2553,7 +2609,7 @@ Theorem n4_65 : ∀ P Q : Prop, ((¬P → Q)↔(P ∨ Q)). intros n4_21a. apply n4_21a. - Qed. +Qed. Theorem n4_66 : ∀ P Q : Prop, (¬P → ¬Q) ↔ (P ∨ ¬Q). @@ -2561,7 +2617,7 @@ Theorem n4_66 : ∀ P Q : Prop, specialize n4_64 with P (¬Q). intros n4_64a. apply n4_64a. - Qed. +Qed. Theorem n4_67 : ∀ P Q : Prop, ¬(¬P → ¬Q) ↔ (¬P ∧ Q). @@ -2587,7 +2643,7 @@ Theorem n4_67 : ∀ P Q : Prop, ((¬P → ¬Q)↔(P ∨ ¬Q)). intros n4_21a. apply n4_21a. - Qed. +Qed. (*Return to this proof.*) (*We did get one half of the ↔.*) @@ -2616,7 +2672,7 @@ Theorem n4_7 : ∀ P Q : Prop, Equiv H. apply H. apply Equiv4_01. - Qed. +Qed. Theorem n4_71 : ∀ P Q : Prop, (P → Q) ↔ (P ↔ (P ∧ Q)). @@ -2651,7 +2707,7 @@ Theorem n4_71 : ∀ P Q : Prop, apply Equiv4_01. apply Equiv4_01. apply Equiv4_01. - Qed. +Qed. Theorem n4_72 : ∀ P Q : Prop, (P → Q) ↔ (Q ↔ (P ∨ Q)). @@ -2705,7 +2761,7 @@ Theorem n4_72 : ∀ P Q : Prop, specialize n4_21 with (Q ∨ P) (¬(¬Q ∧ ¬P)). intros n4_21b. apply n4_21b. - Qed. +Qed. Theorem n4_73 : ∀ P Q : Prop, Q → (P ↔ (P ∧ Q)). @@ -2723,7 +2779,7 @@ Theorem n4_73 : ∀ P Q : Prop, Syll Simp2_02a Simp3_26a Sa. apply Sa. apply Equiv4_01. - Qed. +Qed. Theorem n4_74 : ∀ P Q : Prop, ¬P → (Q ↔ (P ∨ Q)). @@ -2742,7 +2798,7 @@ Theorem n4_74 : ∀ P Q : Prop, specialize n4_21 with (Q↔(P ∨ Q)) (P → Q). intros n4_21a. apply n4_21a. - Qed. +Qed. Theorem n4_76 : ∀ P Q R : Prop, ((P → Q) ∧ (P → R)) ↔ (P → (Q ∧ R)). @@ -2762,7 +2818,7 @@ Theorem n4_76 : ∀ P Q R : Prop, apply Impl1_01. apply Impl1_01. apply Impl1_01. - Qed. +Qed. Theorem n4_77 : ∀ P Q R : Prop, ((Q → P) ∧ (R → P)) ↔ ((Q ∨ R) → P). @@ -2796,7 +2852,7 @@ Theorem n4_77 : ∀ P Q R : Prop, Equiv H. apply H. apply Equiv4_01. - Qed. +Qed. Theorem n4_78 : ∀ P Q R : Prop, ((P → Q) ∨ (P → R)) ↔ (P → (Q ∨ R)). @@ -2859,7 +2915,7 @@ Theorem n4_78 : ∀ P Q R : Prop, rewrite <- Impl1_01. rewrite <- Impl1_01. reflexivity. - Qed. +Qed. Theorem n4_79 : ∀ P Q R : Prop, ((Q → P) ∨ (R → P)) ↔ ((Q ∧ R) → P). @@ -2933,7 +2989,7 @@ Theorem n4_79 : ∀ P Q R : Prop, rewrite <- Prod3_01 in n4_22b. apply n4_22b. apply Equiv4_01. - Qed. +Qed. Theorem n4_8 : ∀ P : Prop, (P → ¬P) ↔ ¬P. @@ -2949,7 +3005,7 @@ Theorem n4_8 : ∀ P : Prop, Equiv H. apply H. apply Equiv4_01. - Qed. +Qed. Theorem n4_81 : ∀ P : Prop, (¬P → P) ↔ P. @@ -2965,7 +3021,7 @@ Theorem n4_81 : ∀ P : Prop, Equiv H. apply H. apply Equiv4_01. - Qed. +Qed. Theorem n4_82 : ∀ P Q : Prop, ((P → Q) ∧ (P → ¬Q)) ↔ ¬P. @@ -2995,7 +3051,7 @@ Theorem n4_82 : ∀ P Q : Prop, Equiv H. apply H. apply Equiv4_01. - Qed. +Qed. Theorem n4_83 : ∀ P Q : Prop, ((P → Q) ∧ (¬P → Q)) ↔ Q. @@ -3025,7 +3081,7 @@ Theorem n4_83 : ∀ P Q : Prop, Equiv H. apply H. apply Equiv4_01. - Qed. +Qed. Theorem n4_84 : ∀ P Q R : Prop, (P ↔ Q) → ((P → R) ↔ (Q → R)). @@ -3055,7 +3111,7 @@ Theorem n4_84 : ∀ P Q R : Prop, apply n4_21a. apply Equiv4_01. apply Equiv4_01. - Qed. +Qed. Theorem n4_85 : ∀ P Q R : Prop, (P ↔ Q) → ((R → P) ↔ (R → Q)). @@ -3111,7 +3167,7 @@ Theorem n4_86 : ∀ P Q R : Prop, specialize n4_21 with P Q. intros n4_21a. apply n4_21a. - Qed. +Qed. Theorem n4_87 : ∀ P Q R : Prop, (((P ∧ Q) → R) ↔ (P → Q → R)) ↔ @@ -3167,7 +3223,7 @@ Theorem n4_87 : ∀ P Q R : Prop, apply Equiv4_01. apply Equiv4_01. apply Equiv4_01. - Qed. +Qed. End No4. @@ -3205,7 +3261,7 @@ Theorem n5_1 : ∀ P Q : Prop, reflexivity. apply EqBi. apply n4_76a. - Qed. +Qed. Theorem n5_11 : ∀ P Q : Prop, (P → Q) ∨ (¬P → Q). @@ -3216,7 +3272,7 @@ Theorem n5_11 : ∀ P Q : Prop, intros n2_54a. MP n2_54a n2_5a. apply n2_54a. - Qed. +Qed. (*The proof sketch cites n2_51, but this may be a misprint.*) @@ -3229,7 +3285,7 @@ Theorem n5_12 : ∀ P Q : Prop, intros n2_54a. MP n2_54a n2_5a. apply n2_54a. - Qed. +Qed. (*The proof sketch cites n2_52, but this may be a misprint.*) @@ -3248,7 +3304,7 @@ Theorem n5_13 : ∀ P Q : Prop, apply n4_13a. rewrite <- Impl1_01. reflexivity. - Qed. +Qed. Theorem n5_14 : ∀ P Q R : Prop, (P → Q) ∨ (Q → R). @@ -3271,7 +3327,7 @@ Theorem n5_14 : ∀ P Q R : Prop, apply n4_13a. rewrite <- Impl1_01. reflexivity. - Qed. +Qed. Theorem n5_15 : ∀ P Q : Prop, (P ↔ Q) ∨ (P ↔ ¬Q). @@ -3357,7 +3413,7 @@ Theorem n5_15 : ∀ P Q : Prop, apply n4_12a. apply Equiv4_01. apply Equiv4_01. - Qed. +Qed. Theorem n5_16 : ∀ P Q : Prop, ¬((P ↔ Q) ∧ (P ↔ ¬Q)). @@ -3466,7 +3522,7 @@ Theorem n5_16 : ∀ P Q : Prop, specialize n4_32 with (P→Q) (P→¬Q) (Q→P). intros n4_32a. apply n4_32a. - Qed. +Qed. Theorem n5_17 : ∀ P Q : Prop, ((P ∨ Q) ∧ ¬(P ∧ Q)) ↔ (P ↔ ¬Q). @@ -3525,7 +3581,7 @@ Theorem n5_17 : ∀ P Q : Prop, apply n4_31a. apply EqBi. apply n4_21a. - Qed. +Qed. Theorem n5_18 : ∀ P Q : Prop, (P ↔ Q) ↔ ¬(P ↔ ¬Q). @@ -3545,7 +3601,7 @@ Theorem n5_18 : ∀ P Q : Prop, apply H. apply EqBi. apply n5_17a. - Qed. +Qed. Theorem n5_19 : ∀ P : Prop, ¬(P ↔ ¬P). @@ -3558,7 +3614,7 @@ Theorem n5_19 : ∀ P : Prop, apply n4_2a. apply EqBi. apply n5_18a. - Qed. +Qed. Theorem n5_21 : ∀ P Q : Prop, (¬P ∧ ¬Q) → (P ↔ Q). @@ -3571,7 +3627,7 @@ Theorem n5_21 : ∀ P Q : Prop, apply n5_1a. apply EqBi. apply Transp4_11a. - Qed. +Qed. Theorem n5_22 : ∀ P Q : Prop, ¬(P ↔ Q) ↔ ((P ∧ ¬Q) ∨ (Q ∧ ¬P)). @@ -3598,7 +3654,7 @@ Theorem n5_22 : ∀ P Q : Prop, apply Equiv4_01. apply EqBi. apply n4_51a. - Qed. +Qed. Theorem n5_23 : ∀ P Q : Prop, (P ↔ Q) ↔ ((P ∧ Q) ∨ (¬P ∧ ¬Q)). @@ -3626,9 +3682,9 @@ Theorem n5_23 : ∀ P Q : Prop, specialize n4_13 with Q. intros n4_13a. apply n4_13a. - Qed. +Qed. (*The proof sketch in Principia offers n4_36. - This seems to be a misprint. We used n4_3.*) + This seems to be a misprint. We used n4_3.*) Theorem n5_24 : ∀ P Q : Prop, ¬((P ∧ Q) ∨ (¬P ∧ ¬Q)) ↔ ((P ∧ ¬Q) ∨ (Q ∧ ¬P)). @@ -3654,7 +3710,7 @@ Theorem n5_24 : ∀ P Q : Prop, intros Transp4_11a. apply EqBi. apply Transp4_11a. (*Not cited*) - Qed. +Qed. Theorem n5_25 : ∀ P Q : Prop, (P ∨ Q) ↔ ((P → Q) → Q). @@ -3670,7 +3726,7 @@ Theorem n5_25 : ∀ P Q : Prop, Equiv H. apply H. apply Equiv4_01. - Qed. +Qed. Theorem n5_3 : ∀ P Q R : Prop, ((P ∧ Q) → R) ↔ ((P ∧ Q) → (P ∧ R)). @@ -3698,7 +3754,7 @@ Theorem n5_3 : ∀ P Q R : Prop, Equiv H. apply H. apply Equiv4_01. - Qed. +Qed. Theorem n5_31 : ∀ P Q R : Prop, (R ∧ (P → Q)) → (P → (Q ∧ R)). @@ -3719,7 +3775,7 @@ Theorem n5_31 : ∀ P Q R : Prop, intros Imp3_31a. (*Not cited*) MP Imp3_31a Sb. apply Imp3_31a. - Qed. +Qed. Theorem n5_32 : ∀ P Q R : Prop, (P → (Q ↔ R)) ↔ ((P ∧ Q) ↔ (P ∧ R)). @@ -3779,7 +3835,7 @@ Theorem n5_32 : ∀ P Q R : Prop, apply H. apply Equiv4_01. apply Equiv4_01. - Qed. +Qed. Theorem n5_33 : ∀ P Q R : Prop, (P ∧ (Q → R)) ↔ (P ∧ ((P ∧ Q) → R)). @@ -3811,7 +3867,7 @@ Theorem n5_33 : ∀ P Q R : Prop, intros n4_3a. apply n4_3a. (*Not cited*) apply Equiv4_01. - Qed. +Qed. Theorem n5_35 : ∀ P Q R : Prop, ((P → Q) ∧ (P → R)) → (P → (Q ↔ R)). @@ -3825,7 +3881,7 @@ Theorem n5_35 : ∀ P Q R : Prop, MP Syll2_05a n5_1a. Syll Comp3_43a Syll2_05a Sa. apply Sa. - Qed. +Qed. Theorem n5_36 : ∀ P Q : Prop, (P ∧ (P ↔ Q)) ↔ (Q ∧ (P ↔ Q)). @@ -3852,7 +3908,7 @@ Theorem n5_36 : ∀ P Q : Prop, reflexivity. apply EqBi. apply n5_32a. - Qed. +Qed. (*The proof sketch cites Ass3_35 and n4_38, but the sketch was indecipherable.*) @@ -3870,7 +3926,7 @@ Theorem n5_4 : ∀ P Q : Prop, Equiv H. apply H. apply Equiv4_01. - Qed. +Qed. Theorem n5_41 : ∀ P Q R : Prop, ((P → Q) → (P → R)) ↔ (P → Q → R). @@ -3886,7 +3942,7 @@ Theorem n5_41 : ∀ P Q R : Prop, Equiv H. apply H. apply Equiv4_01. - Qed. +Qed. Theorem n5_42 : ∀ P Q R : Prop, (P → Q → R) ↔ (P → Q → P ∧ R). @@ -3925,7 +3981,7 @@ Theorem n5_42 : ∀ P Q R : Prop, apply EqBi. apply H. apply Equiv4_01. - Qed. +Qed. Theorem n5_44 : ∀ P Q R : Prop, (P→Q) → ((P → R) ↔ (P → (Q ∧ R))). @@ -3992,7 +4048,7 @@ Theorem n5_44 : ∀ P Q R : Prop, apply EqBi. apply n4_21a. apply Equiv4_01. - Qed. +Qed. Theorem n5_5 : ∀ P Q : Prop, P → ((P → Q) ↔ Q). @@ -4027,7 +4083,7 @@ Theorem n5_5 : ∀ P Q : Prop, specialize n4_24 with P. intros n4_24a. (*Not cited*) apply n4_24a. - Qed. +Qed. Theorem n5_501 : ∀ P Q : Prop, P → (Q ↔ (P ↔ Q)). @@ -4075,7 +4131,7 @@ Theorem n5_501 : ∀ P Q : Prop, specialize n4_32 with P (P→Q) (Q→P). intros n4_32a. (*Not cited*) apply n4_32a. - Qed. +Qed. Theorem n5_53 : ∀ P Q R S : Prop, (((P ∨ Q) ∨ R) → S) ↔ (((P → S) ∧ (Q → S)) ∧ (R → S)). @@ -4098,7 +4154,7 @@ Theorem n5_53 : ∀ P Q R S : Prop, apply n4_21a. (*Not cited*) apply EqBi. apply n4_77b. - Qed. +Qed. Theorem n5_54 : ∀ P Q : Prop, ((P ∧ Q) ↔ P) ∨ ((P ∧ Q) ↔ Q). @@ -4162,7 +4218,7 @@ Theorem n5_54 : ∀ P Q : Prop, specialize n4_3 with P Q. intros n4_3a. (*Not cited*) apply n4_3a. - Qed. +Qed. Theorem n5_55 : ∀ P Q : Prop, ((P ∨ Q) ↔ P) ∨ ((P ∨ Q) ↔ Q). @@ -4231,7 +4287,7 @@ Theorem n5_55 : ∀ P Q : Prop, specialize n4_31 with P (P ∧ Q). intros n4_31d. (*Not cited*) apply n4_31d. - Qed. +Qed. Theorem n5_6 : ∀ P Q R : Prop, ((P ∧ ¬Q) → R) ↔ (P → (Q ∨ R)). @@ -4271,7 +4327,7 @@ Theorem n5_6 : ∀ P Q R : Prop, apply n4_64a. apply Equiv4_01. apply Equiv4_01. - Qed. +Qed. Theorem n5_61 : ∀ P Q : Prop, ((P ∨ Q) ∧ ¬Q) ↔ (P ∧ ¬Q). @@ -4309,7 +4365,7 @@ Theorem n5_61 : ∀ P Q : Prop, reflexivity. apply EqBi. apply n5_32a. - Qed. +Qed. Theorem n5_62 : ∀ P Q : Prop, ((P ∧ Q) ∨ ¬Q) ↔ (P ∨ ¬Q). @@ -4344,7 +4400,7 @@ Theorem n5_62 : ∀ P Q : Prop, reflexivity. rewrite <- Impl1_01. reflexivity. - Qed. +Qed. Theorem n5_63 : ∀ P Q : Prop, (P ∨ Q) ↔ (P ∨ (¬P ∧ Q)). @@ -4378,7 +4434,7 @@ Theorem n5_63 : ∀ P Q : Prop, specialize n4_13 with P. intros n4_13a. (*Not cited*) apply n4_13a. - Qed. +Qed. Theorem n5_7 : ∀ P Q R : Prop, ((P ∨ R) ↔ (Q ∨ R)) ↔ (R ∨ (P ↔ Q)). @@ -4582,7 +4638,7 @@ Theorem n5_71 : ∀ P Q R : Prop, intros n4_31b. (*Not cited*) apply n4_31b. apply Equiv4_01. - Qed. +Qed. Theorem n5_74 : ∀ P Q R : Prop, (P → (Q ↔ R)) ↔ ((P → Q) ↔ (P → R)). @@ -4621,7 +4677,7 @@ Theorem n5_74 : ∀ P Q R : Prop, apply n4_76a. apply Equiv4_01. apply Equiv4_01. - Qed. +Qed. Theorem n5_75 : ∀ P Q R : Prop, ((R → ¬Q) ∧ (P ↔ Q ∨ R)) → ((P ∧ ¬Q) ↔ R). @@ -4695,6 +4751,6 @@ Theorem n5_75 : ∀ P Q R : Prop, apply Equiv4_01. apply Equiv4_01. apply Equiv4_01. - Qed. +Qed. End No5.
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