Theorem TTIid 14114

Description: A -> identity.

Assertion

Ref	Expression
TTIid	|- (( T. -> T. ) <-> T. )

Proof of Theorem TTIid

Step	Hyp	Ref	Expression
1		tru 1264	. . 3 |- T.
2	1	a1i 8	. 2 |- ( T. -> T. )
3	2, 1	2th 786	1 |- (( T. -> T. ) <-> T. )

Syntax hints:   -> wi 3   <-> wb 163   T. wtru 1260

This theorem was proved from axioms:  ax-1 4  ax-2 5  ax-3 6  ax-mp 7

This theorem depends on definitions:  df-bi 164  df-tru 1262

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