Theorem pm2.07 385

Description: Theorem *2.07 of [WhiteheadRussell] p. 101. (Contributed by NM, 3-Jan-2005.)

Assertion

Ref	Expression
pm2.07	⊢ (φ → (φ ∨ φ))

Proof of Theorem pm2.07

Step	Hyp	Ref	Expression
1		olc 373	1 ⊢ (φ → (φ ∨ φ))

Syntax hints:   → wi 4   ∨ wo 357

This theorem was proved from axioms:  ax-mp 5  ax-1 6  ax-2 7  ax-3 8

This theorem depends on definitions:  df-bi 177  df-or 359

This theorem is referenced by:  oridm  500