Theorem idd 11

Description: Principle of identity with antecedent.

Assertion

Ref	Expression
idd	⊢ (φ → (ψ → ψ))

Proof of Theorem idd

Step	Hyp	Ref	Expression
1		id 9	. 2 ⊢ (ψ → ψ)
2	1	a1i 7	1 ⊢ (φ → (ψ → ψ))

Syntax hints:   → wi 2

This theorem is referenced by:  anim1d 432  anim2d 433  orim1d 437  orim2d 438  dedlema 569  a16g 933  r19.36av 1299  r19.44av 1305  r19.45av 1306  elnnz 4572

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

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