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Metamath Proof Explorer


Theorem iden2

Description: Virtual deduction identity rule. simpr in conjunction form Virtual Deduction notation. (Contributed by Alan Sare, 5-Sep-2016) (Proof modification is discouraged.) (New usage is discouraged.)

Ref Expression
Assertion iden2 φ ψ ψ

Proof

Step Hyp Ref Expression
1 simpr φ ψ ψ
2 dfvd2an φ ψ ψ φ ψ ψ
3 1 2 mpbir φ ψ ψ