# HG changeset patch # User wenzelm # Date 1149716664 -7200 # Node ID ecf1b1b5576db87fa0964a4f2226a386dca59f70 # Parent 0d7564c798d04c04516765b088acc4b396cd9824 removed obsolete ML files; diff -r 0d7564c798d0 -r ecf1b1b5576d src/FOL/ex/int.ML --- a/src/FOL/ex/int.ML Wed Jun 07 23:34:37 2006 +0200 +++ /dev/null Thu Jan 01 00:00:00 1970 +0000 @@ -1,478 +0,0 @@ -(* Title: FOL/ex/int.ML - ID: $Id$ - Author: Lawrence C Paulson, Cambridge University Computer Laboratory - Copyright 1991 University of Cambridge - -Intuitionistic First-Order Logic. - -Single-step commands: -by (IntPr.step_tac 1); -by (biresolve_tac safe_brls 1); -by (biresolve_tac haz_brls 1); -by (assume_tac 1); -by (IntPr.safe_tac 1); -by (IntPr.mp_tac 1); -by (IntPr.fast_tac 1); -*) - - -(*Metatheorem (for PROPOSITIONAL formulae...): - P is classically provable iff ~~P is intuitionistically provable. - Therefore ~P is classically provable iff it is intuitionistically provable. - -Proof: Let Q be the conjuction of the propositions A|~A, one for each atom A -in P. Now ~~Q is intuitionistically provable because ~~(A|~A) is and because -~~ distributes over &. If P is provable classically, then clearly Q-->P is -provable intuitionistically, so ~~(Q-->P) is also provable intuitionistically. -The latter is intuitionistically equivalent to ~~Q-->~~P, hence to ~~P, since -~~Q is intuitionistically provable. Finally, if P is a negation then ~~P is -intuitionstically equivalent to P. [Andy Pitts] *) - -Goal "~~(P&Q) <-> ~~P & ~~Q"; -by (IntPr.fast_tac 1); -qed ""; - -Goal "~~ ((~P --> Q) --> (~P --> ~Q) --> P)"; -by (IntPr.fast_tac 1); -qed ""; - -(* ~~ does NOT distribute over | *) - -Goal "~~(P-->Q) <-> (~~P --> ~~Q)"; -by (IntPr.fast_tac 1); -qed ""; - -Goal "~~~P <-> ~P"; -by (IntPr.fast_tac 1); -qed ""; - -Goal "~~((P --> Q | R) --> (P-->Q) | (P-->R))"; -by (IntPr.fast_tac 1); -qed ""; - -Goal "(P<->Q) <-> (Q<->P)"; -by (IntPr.fast_tac 1); -qed ""; - -Goal "((P --> (Q | (Q-->R))) --> R) --> R"; -by (IntPr.fast_tac 1); -qed ""; - -Goal "(((G-->A) --> J) --> D --> E) --> (((H-->B)-->I)-->C-->J) \ -\ --> (A-->H) --> F --> G --> (((C-->B)-->I)-->D)-->(A-->C) \ -\ --> (((F-->A)-->B) --> I) --> E"; -by (IntPr.fast_tac 1); -qed ""; - - -writeln"Lemmas for the propositional double-negation translation"; - -Goal "P --> ~~P"; -by (IntPr.fast_tac 1); -qed ""; - -Goal "~~(~~P --> P)"; -by (IntPr.fast_tac 1); -qed ""; - -Goal "~~P & ~~(P --> Q) --> ~~Q"; -by (IntPr.fast_tac 1); -qed ""; - - -writeln"The following are classically but not constructively valid."; - -(*The attempt to prove them terminates quickly!*) -Goal "((P-->Q) --> P) --> P"; -by (IntPr.fast_tac 1) handle ERROR _ => writeln"Failed, as expected"; -(*Check that subgoals remain: proof failed.*) -getgoal 1; - -Goal "(P&Q-->R) --> (P-->R) | (Q-->R)"; -by (IntPr.fast_tac 1) handle ERROR _ => writeln"Failed, as expected"; -getgoal 1; - - -writeln"de Bruijn formulae"; - -(*de Bruijn formula with three predicates*) -Goal "((P<->Q) --> P&Q&R) & \ -\ ((Q<->R) --> P&Q&R) & \ -\ ((R<->P) --> P&Q&R) --> P&Q&R"; -by (IntPr.fast_tac 1); -qed ""; - - -(*de Bruijn formula with five predicates*) -Goal "((P<->Q) --> P&Q&R&S&T) & \ -\ ((Q<->R) --> P&Q&R&S&T) & \ -\ ((R<->S) --> P&Q&R&S&T) & \ -\ ((S<->T) --> P&Q&R&S&T) & \ -\ ((T<->P) --> P&Q&R&S&T) --> P&Q&R&S&T"; -by (IntPr.fast_tac 1); -qed ""; - - -(*** Problems from of Sahlin, Franzen and Haridi, - An Intuitionistic Predicate Logic Theorem Prover. - J. Logic and Comp. 2 (5), October 1992, 619-656. -***) - -(*Problem 1.1*) -Goal "(ALL x. EX y. ALL z. p(x) & q(y) & r(z)) <-> \ -\ (ALL z. EX y. ALL x. p(x) & q(y) & r(z))"; -(* -by (IntPr.best_dup_tac 1); (*65 seconds on a Pentium III! Is it worth it?*) -*) - -(*Problem 3.1*) -Goal "~ (EX x. ALL y. mem(y,x) <-> ~ mem(x,x))"; -by (IntPr.fast_tac 1); -qed ""; - -(*Problem 4.1: hopeless!*) -Goal "(ALL x. p(x) --> p(h(x)) | p(g(x))) & (EX x. p(x)) & (ALL x. ~p(h(x))) \ -\ --> (EX x. p(g(g(g(g(g(x)))))))"; - - -writeln"Intuitionistic FOL: propositional problems based on Pelletier."; - -writeln"Problem ~~1"; -Goal "~~((P-->Q) <-> (~Q --> ~P))"; -by (IntPr.fast_tac 1); -qed ""; - - -writeln"Problem ~~2"; -Goal "~~(~~P <-> P)"; -by (IntPr.fast_tac 1); -qed ""; -(*1 secs*) - - -writeln"Problem 3"; -Goal "~(P-->Q) --> (Q-->P)"; -by (IntPr.fast_tac 1); -qed ""; - -writeln"Problem ~~4"; -Goal "~~((~P-->Q) <-> (~Q --> P))"; -by (IntPr.fast_tac 1); -qed ""; -(*9 secs*) - -writeln"Problem ~~5"; -Goal "~~((P|Q-->P|R) --> P|(Q-->R))"; -by (IntPr.fast_tac 1); -qed ""; -(*10 secs*) - - -writeln"Problem ~~6"; -Goal "~~(P | ~P)"; -by (IntPr.fast_tac 1); -qed ""; - -writeln"Problem ~~7"; -Goal "~~(P | ~~~P)"; -by (IntPr.fast_tac 1); -qed ""; - -writeln"Problem ~~8. Peirce's law"; -Goal "~~(((P-->Q) --> P) --> P)"; -by (IntPr.fast_tac 1); -qed ""; - -writeln"Problem 9"; -Goal "((P|Q) & (~P|Q) & (P| ~Q)) --> ~ (~P | ~Q)"; -by (IntPr.fast_tac 1); -qed ""; -(*9 secs*) - - -writeln"Problem 10"; -Goal "(Q-->R) --> (R-->P&Q) --> (P-->(Q|R)) --> (P<->Q)"; -by (IntPr.fast_tac 1); -qed ""; - -writeln"11. Proved in each direction (incorrectly, says Pelletier!!) "; -Goal "P<->P"; -by (IntPr.fast_tac 1); - -writeln"Problem ~~12. Dijkstra's law "; -Goal "~~(((P <-> Q) <-> R) <-> (P <-> (Q <-> R)))"; -by (IntPr.fast_tac 1); -qed ""; - -Goal "((P <-> Q) <-> R) --> ~~(P <-> (Q <-> R))"; -by (IntPr.fast_tac 1); -qed ""; - -writeln"Problem 13. Distributive law"; -Goal "P | (Q & R) <-> (P | Q) & (P | R)"; -by (IntPr.fast_tac 1); -qed ""; - -writeln"Problem ~~14"; -Goal "~~((P <-> Q) <-> ((Q | ~P) & (~Q|P)))"; -by (IntPr.fast_tac 1); -qed ""; - -writeln"Problem ~~15"; -Goal "~~((P --> Q) <-> (~P | Q))"; -by (IntPr.fast_tac 1); -qed ""; - -writeln"Problem ~~16"; -Goal "~~((P-->Q) | (Q-->P))"; -by (IntPr.fast_tac 1); -qed ""; - -writeln"Problem ~~17"; -Goal - "~~(((P & (Q-->R))-->S) <-> ((~P | Q | S) & (~P | ~R | S)))"; -by (IntPr.fast_tac 1); -qed ""; - -(*Dijkstra's "Golden Rule"*) -Goal "(P&Q) <-> P <-> Q <-> (P|Q)"; -by (IntPr.fast_tac 1); -qed ""; - - -writeln"****Examples with quantifiers****"; - - -writeln"The converse is classical in the following implications..."; - -Goal "(EX x. P(x)-->Q) --> (ALL x. P(x)) --> Q"; -by (IntPr.fast_tac 1); -qed ""; - -Goal "((ALL x. P(x))-->Q) --> ~ (ALL x. P(x) & ~Q)"; -by (IntPr.fast_tac 1); -qed ""; - -Goal "((ALL x. ~P(x))-->Q) --> ~ (ALL x. ~ (P(x)|Q))"; -by (IntPr.fast_tac 1); -qed ""; - -Goal "(ALL x. P(x)) | Q --> (ALL x. P(x) | Q)"; -by (IntPr.fast_tac 1); -qed ""; - -Goal "(EX x. P --> Q(x)) --> (P --> (EX x. Q(x)))"; -by (IntPr.fast_tac 1); -qed ""; - - - - -writeln"The following are not constructively valid!"; -(*The attempt to prove them terminates quickly!*) - -Goal "((ALL x. P(x))-->Q) --> (EX x. P(x)-->Q)"; -by (IntPr.fast_tac 1) handle ERROR _ => writeln"Failed, as expected"; -getgoal 1; - -Goal "(P --> (EX x. Q(x))) --> (EX x. P-->Q(x))"; -by (IntPr.fast_tac 1) handle ERROR _ => writeln"Failed, as expected"; -getgoal 1; - -Goal "(ALL x. P(x) | Q) --> ((ALL x. P(x)) | Q)"; -by (IntPr.fast_tac 1) handle ERROR _ => writeln"Failed, as expected"; -getgoal 1; - -Goal "(ALL x. ~~P(x)) --> ~~(ALL x. P(x))"; -by (IntPr.fast_tac 1) handle ERROR _ => writeln"Failed, as expected"; -getgoal 1; - -(*Classically but not intuitionistically valid. Proved by a bug in 1986!*) -Goal "EX x. Q(x) --> (ALL x. Q(x))"; -by (IntPr.fast_tac 1) handle ERROR _ => writeln"Failed, as expected"; -getgoal 1; - - -writeln"Hard examples with quantifiers"; - -(*The ones that have not been proved are not known to be valid! - Some will require quantifier duplication -- not currently available*) - -writeln"Problem ~~18"; -Goal "~~(EX y. ALL x. P(y)-->P(x))"; -(*NOT PROVED*) - -writeln"Problem ~~19"; -Goal "~~(EX x. ALL y z. (P(y)-->Q(z)) --> (P(x)-->Q(x)))"; -(*NOT PROVED*) - -writeln"Problem 20"; -Goal "(ALL x y. EX z. ALL w. (P(x)&Q(y)-->R(z)&S(w))) \ -\ --> (EX x y. P(x) & Q(y)) --> (EX z. R(z))"; -by (IntPr.fast_tac 1); -qed ""; - -writeln"Problem 21"; -Goal "(EX x. P-->Q(x)) & (EX x. Q(x)-->P) --> ~~(EX x. P<->Q(x))"; -(*NOT PROVED; needs quantifier duplication*) - -writeln"Problem 22"; -Goal "(ALL x. P <-> Q(x)) --> (P <-> (ALL x. Q(x)))"; -by (IntPr.fast_tac 1); -qed ""; - -writeln"Problem ~~23"; -Goal "~~ ((ALL x. P | Q(x)) <-> (P | (ALL x. Q(x))))"; -by (IntPr.fast_tac 1); -qed ""; - -writeln"Problem 24"; -Goal "~(EX x. S(x)&Q(x)) & (ALL x. P(x) --> Q(x)|R(x)) & \ -\ (~(EX x. P(x)) --> (EX x. Q(x))) & (ALL x. Q(x)|R(x) --> S(x)) \ -\ --> ~~(EX x. P(x)&R(x))"; -(*Not clear why fast_tac, best_tac, ASTAR and ITER_DEEPEN all take forever*) -by IntPr.safe_tac; -by (etac impE 1); -by (IntPr.fast_tac 1); -by (IntPr.fast_tac 1); -qed ""; - -writeln"Problem 25"; -Goal "(EX x. P(x)) & \ -\ (ALL x. L(x) --> ~ (M(x) & R(x))) & \ -\ (ALL x. P(x) --> (M(x) & L(x))) & \ -\ ((ALL x. P(x)-->Q(x)) | (EX x. P(x)&R(x))) \ -\ --> (EX x. Q(x)&P(x))"; -by (IntPr.fast_tac 1); -qed ""; - -writeln"Problem ~~26"; -Goal "(~~(EX x. p(x)) <-> ~~(EX x. q(x))) & \ -\ (ALL x. ALL y. p(x) & q(y) --> (r(x) <-> s(y))) \ -\ --> ((ALL x. p(x)-->r(x)) <-> (ALL x. q(x)-->s(x)))"; -(*NOT PROVED*) - -writeln"Problem 27"; -Goal "(EX x. P(x) & ~Q(x)) & \ -\ (ALL x. P(x) --> R(x)) & \ -\ (ALL x. M(x) & L(x) --> P(x)) & \ -\ ((EX x. R(x) & ~ Q(x)) --> (ALL x. L(x) --> ~ R(x))) \ -\ --> (ALL x. M(x) --> ~L(x))"; -by (IntPr.fast_tac 1); (*21 secs*) -qed ""; - -writeln"Problem ~~28. AMENDED"; -Goal "(ALL x. P(x) --> (ALL x. Q(x))) & \ -\ (~~(ALL x. Q(x)|R(x)) --> (EX x. Q(x)&S(x))) & \ -\ (~~(EX x. S(x)) --> (ALL x. L(x) --> M(x))) \ -\ --> (ALL x. P(x) & L(x) --> M(x))"; -by (IntPr.fast_tac 1); (*48 secs*) -qed ""; - -writeln"Problem 29. Essentially the same as Principia Mathematica *11.71"; -Goal "(EX x. P(x)) & (EX y. Q(y)) \ -\ --> ((ALL x. P(x)-->R(x)) & (ALL y. Q(y)-->S(y)) <-> \ -\ (ALL x y. P(x) & Q(y) --> R(x) & S(y)))"; -by (IntPr.fast_tac 1); -qed ""; - -writeln"Problem ~~30"; -Goal "(ALL x. (P(x) | Q(x)) --> ~ R(x)) & \ -\ (ALL x. (Q(x) --> ~ S(x)) --> P(x) & R(x)) \ -\ --> (ALL x. ~~S(x))"; -by (IntPr.fast_tac 1); -qed ""; - -writeln"Problem 31"; -Goal "~(EX x. P(x) & (Q(x) | R(x))) & \ -\ (EX x. L(x) & P(x)) & \ -\ (ALL x. ~ R(x) --> M(x)) \ -\ --> (EX x. L(x) & M(x))"; -by (IntPr.fast_tac 1); -qed ""; - -writeln"Problem 32"; -Goal "(ALL x. P(x) & (Q(x)|R(x))-->S(x)) & \ -\ (ALL x. S(x) & R(x) --> L(x)) & \ -\ (ALL x. M(x) --> R(x)) \ -\ --> (ALL x. P(x) & M(x) --> L(x))"; -by (IntPr.fast_tac 1); -qed ""; - -writeln"Problem ~~33"; -Goal "(ALL x. ~~(P(a) & (P(x)-->P(b))-->P(c))) <-> \ -\ (ALL x. ~~((~P(a) | P(x) | P(c)) & (~P(a) | ~P(b) | P(c))))"; -by (IntPr.best_tac 1); (*1.67s*) -qed ""; - - -writeln"Problem 36"; -Goal - "(ALL x. EX y. J(x,y)) & \ -\ (ALL x. EX y. G(x,y)) & \ -\ (ALL x y. J(x,y) | G(x,y) --> (ALL z. J(y,z) | G(y,z) --> H(x,z))) \ -\ --> (ALL x. EX y. H(x,y))"; -by (IntPr.fast_tac 1); (*5 secs*) -qed ""; - -writeln"Problem 37"; -Goal - "(ALL z. EX w. ALL x. EX y. \ -\ ~~(P(x,z)-->P(y,w)) & P(y,z) & (P(y,w) --> (EX u. Q(u,w)))) & \ -\ (ALL x z. ~P(x,z) --> (EX y. Q(y,z))) & \ -\ (~~(EX x y. Q(x,y)) --> (ALL x. R(x,x))) \ -\ --> ~~(ALL x. EX y. R(x,y))"; -(*NOT PROVED*) - -writeln"Problem 39"; -Goal "~ (EX x. ALL y. F(y,x) <-> ~F(y,y))"; -by (IntPr.fast_tac 1); -qed ""; - -writeln"Problem 40. AMENDED"; -Goal "(EX y. ALL x. F(x,y) <-> F(x,x)) --> \ -\ ~(ALL x. EX y. ALL z. F(z,y) <-> ~ F(z,x))"; -by (IntPr.fast_tac 1); -qed ""; - -writeln"Problem 44"; -Goal "(ALL x. f(x) --> \ -\ (EX y. g(y) & h(x,y) & (EX y. g(y) & ~ h(x,y)))) & \ -\ (EX x. j(x) & (ALL y. g(y) --> h(x,y))) \ -\ --> (EX x. j(x) & ~f(x))"; -by (IntPr.fast_tac 1); -qed ""; - -writeln"Problem 48"; -Goal "(a=b | c=d) & (a=c | b=d) --> a=d | b=c"; -by (IntPr.fast_tac 1); -qed ""; - -writeln"Problem 51"; -Goal "(EX z w. ALL x y. P(x,y) <-> (x=z & y=w)) --> \ -\ (EX z. ALL x. EX w. (ALL y. P(x,y) <-> y=w) <-> x=z)"; -by (IntPr.fast_tac 1); -qed ""; - -writeln"Problem 52"; -(*Almost the same as 51. *) -Goal "(EX z w. ALL x y. P(x,y) <-> (x=z & y=w)) --> \ -\ (EX w. ALL y. EX z. (ALL x. P(x,y) <-> x=z) <-> y=w)"; -by (IntPr.fast_tac 1); -qed ""; - -writeln"Problem 56"; -Goal "(ALL x. (EX y. P(y) & x=f(y)) --> P(x)) <-> (ALL x. P(x) --> P(f(x)))"; -by (IntPr.fast_tac 1); -qed ""; - -writeln"Problem 57"; -Goal "P(f(a,b), f(b,c)) & P(f(b,c), f(a,c)) & \ -\ (ALL x y z. P(x,y) & P(y,z) --> P(x,z)) --> P(f(a,b), f(a,c))"; -by (IntPr.fast_tac 1); -qed ""; - -writeln"Problem 60"; -Goal "ALL x. P(x,f(x)) <-> (EX y. (ALL z. P(z,y) --> P(z,f(x))) & P(x,y))"; -by (IntPr.fast_tac 1); -qed ""; diff -r 0d7564c798d0 -r ecf1b1b5576d src/FOL/ex/int.thy --- a/src/FOL/ex/int.thy Wed Jun 07 23:34:37 2006 +0200 +++ /dev/null Thu Jan 01 00:00:00 1970 +0000 @@ -1,11 +0,0 @@ -(* Title: FOL/ex/int.thy - ID: $Id$ - Author: Lawrence C Paulson, Cambridge University Computer Laboratory - Copyright 1991 University of Cambridge - -Intuitionistic First-Order Logic. -*) - -theory int imports IFOL begin - -end