Theorem pm2.46 895

Description: Theorem *2.46 of [WhiteheadRussell] p. 106. (Contributed by NM, 3-Jan-2005.)

Assertion

Ref	Expression
pm2.46	⊢ (¬ (𝜑 ∨ 𝜓) → ¬ 𝜓)

Proof of Theorem pm2.46

Step	Hyp	Ref	Expression
1		olc 881	. 2 ⊢ (𝜓 → (𝜑 ∨ 𝜓))
2	1	con3i 155	1 ⊢ (¬ (𝜑 ∨ 𝜓) → ¬ 𝜓)

Syntax hints:  ¬ wn 3   → wi 4   ∨ wo 860

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 210  df-or 861

This theorem is referenced by:  pm2.48  897  pm2.49  898  rb-ax3  1784  eueq3  3675  soasym  5604  ltnsym  11309  tglineneq  28899  expgt0b  33142  unbdqndv2lem1  37079  oexpreposd  43064  nnfoctbdjlem  47152