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Theorem idi 1
Description: (Note: This inference rule and the next one, a1ii 2, will normally never appear in a completed proof. They can be ignored if you are using this database to assist learning logic; please start with the statement wn 3 instead.)

This inference says "if φ is true then φ is true". This inference requires no axioms for its proof, and is useful as a copy-paste mechanism during proof development in mmj2. It is normally not referenced in the final version of a proof, since it is always redundant. You can remove this using the metamath-exe (Metamath program) Proof Assistant using the "MM-PA> MINIMIZEWITH *" command. This is the inference associated with id 19, hence its name. (Contributed by Alan Sare, 31-Dec-2011.) (Proof modification is discouraged.) (New usage is discouraged.)

Ref Expression
idi.1 φ
Ref Expression
idi φ

Proof of Theorem idi
StepHypRef Expression
1 idi.1 1 φ
Colors of variables: wff setvar class
This theorem is referenced by: (None)
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