Theorem axc16g-o 39741

Description: A generalization of Axiom ax-c16 39699. Version of axc16g 2298 using ax-c11 39694. (Contributed by NM, 15-May-1993.) (Proof shortened by Andrew Salmon, 25-May-2011.) (Proof modification is discouraged.) (New usage is discouraged.)

Assertion

Ref	Expression
axc16g-o	⊢ (∀𝑥 𝑥 = 𝑦 → (𝜑 → ∀𝑧𝜑))

Distinct variable group:   𝑥,𝑦

Allowed substitution hints:   𝜑(𝑥, 𝑦, 𝑧)

Proof of Theorem axc16g-o

Step	Hyp	Ref	Expression
1		aev-o 39738	. 2 ⊢ (∀𝑥 𝑥 = 𝑦 → ∀𝑧 𝑧 = 𝑥)
2		ax-c16 39699	. 2 ⊢ (∀𝑥 𝑥 = 𝑦 → (𝜑 → ∀𝑥𝜑))
3		biidd 265	. . . 4 ⊢ (∀𝑧 𝑧 = 𝑥 → (𝜑 ↔ 𝜑))
4	3	dral1-o 39711	. . 3 ⊢ (∀𝑧 𝑧 = 𝑥 → (∀𝑧𝜑 ↔ ∀𝑥𝜑))
5	4	biimprd 251	. 2 ⊢ (∀𝑧 𝑧 = 𝑥 → (∀𝑥𝜑 → ∀𝑧𝜑))
6	1, 2, 5	sylsyld 62	1 ⊢ (∀𝑥 𝑥 = 𝑦 → (𝜑 → ∀𝑧𝜑))

This proof depends on syntax axioms:   → wi 4  ∀wal 1568

This proof depends on axioms:  ax-mp 5  ax-1 6  ax-2 7  ax-3 8  ax-gen 1828  ax-4 1842  ax-5 1943  ax-6 2000  ax-7 2041  ax-11 2195  ax-c5 39690  ax-c4 39691  ax-c7 39692  ax-c10 39693  ax-c11 39694  ax-c9 39697  ax-c16 39699

This proof depends on definitions:  df-bi 210  df-an 402  df-ex 1813

This theorem is used by:  ax12inda2  39754