src/FOL/IFOL.thy
author lcp
Tue, 05 Oct 1993 15:32:29 +0100
changeset 26 5aa9c39b480d
parent 0 a5a9c433f639
child 35 d71f96f1780e
permissions -rw-r--r--
ordinal: DEFINITION of < and le to replace : and <= on ordinals! Many changes epsilon,arith: many changes ordinal/succ_mem_succI/E: deleted; use succ_leI/E nat/nat_0_in_succ: deleted; use nat_0_le univ/Vset_rankI: deleted; use VsetI

IFOL = Pure + 

classes term < logic

default term

types o 0

arities o :: logic

consts	
    Trueprop	::	"o => prop"		("(_)" [0] 5)
    True,False	::	"o"
  (*Connectives*)
    "="		::	"['a,'a] => o"		(infixl 50)
    Not		::	"o => o"		("~ _" [40] 40)
    "&"		::	"[o,o] => o"		(infixr 35)
    "|"		::	"[o,o] => o"		(infixr 30)
    "-->"	::	"[o,o] => o"		(infixr 25)
    "<->"	::	"[o,o] => o"		(infixr 25)
  (*Quantifiers*)
    All		::	"('a => o) => o"	(binder "ALL " 10)
    Ex		::	"('a => o) => o"	(binder "EX " 10)
    Ex1		::	"('a => o) => o"	(binder "EX! " 10)

rules

  (*Equality*)

refl		"a=a"
subst		"[| a=b;  P(a) |] ==> P(b)"

  (*Propositional logic*)

conjI		"[| P;  Q |] ==> P&Q"
conjunct1	"P&Q ==> P"
conjunct2	"P&Q ==> Q"

disjI1		"P ==> P|Q"
disjI2		"Q ==> P|Q"
disjE		"[| P|Q;  P ==> R;  Q ==> R |] ==> R"

impI		"(P ==> Q) ==> P-->Q"
mp		"[| P-->Q;  P |] ==> Q"

FalseE		"False ==> P"

  (*Definitions*)

True_def	"True == False-->False"
not_def		"~P == P-->False"
iff_def		"P<->Q == (P-->Q) & (Q-->P)"

  (*Unique existence*)
ex1_def		"EX! x. P(x) == EX x. P(x) & (ALL y. P(y) --> y=x)"

  (*Quantifiers*)

allI		"(!!x. P(x)) ==> (ALL x.P(x))"
spec		"(ALL x.P(x)) ==> P(x)"

exI		"P(x) ==> (EX x.P(x))"
exE		"[| EX x.P(x);  !!x. P(x) ==> R |] ==> R"

  (* Reflection *)

eq_reflection  "(x=y)   ==> (x==y)"
iff_reflection "(P<->Q) ==> (P==Q)"

end