Theorem 19.21bbi 2181

Description: Inference removing two universal quantifiers. Version of 19.21bi 2180 with two quantifiers. (Contributed by NM, 20-Apr-1994.)

Hypothesis

Ref	Expression
19.21bbi.1	⊢ (𝜑 → ∀𝑥∀𝑦𝜓)

Assertion

Ref	Expression
19.21bbi	⊢ (𝜑 → 𝜓)

Proof of Theorem 19.21bbi

Step	Hyp	Ref	Expression
1		19.21bbi.1	. . 3 ⊢ (𝜑 → ∀𝑥∀𝑦𝜓)
2	1	19.21bi 2180	. 2 ⊢ (𝜑 → ∀𝑦𝜓)
3	2	19.21bi 2180	1 ⊢ (𝜑 → 𝜓)

Syntax hints:   → wi 4  ∀wal 1528

This theorem was proved from axioms:  ax-mp 5  ax-1 6  ax-2 7  ax-3 8  ax-gen 1789  ax-4 1803  ax-5 1904  ax-6 1963  ax-7 2008  ax-12 2169

This theorem depends on definitions:  df-bi 209  df-ex 1774

This theorem is referenced by:  2mo  2727  pocl  5474  funun  6393  fununi  6422  trclfvcotr  14361  acycgrcycl  32387  pm14.24  40754