Theorem nfsabg 2753

Description: Bound-variable hypothesis builder for a class abstraction. Usage of this theorem is discouraged because it depends on ax-13 2403. See nfsab 2752 for a version with more disjoint variable conditions, but not requiring ax-13 2403. (Contributed by Mario Carneiro, 11-Aug-2016.) (New usage is discouraged.)

Hypothesis

Ref	Expression
nfsabg.1	⊢ Ⅎ𝑥𝜑

Assertion

Ref	Expression
nfsabg	⊢ Ⅎ𝑥 𝑧 ∈ {𝑦 ∣ 𝜑}

Distinct variable group:   𝑥,𝑧

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

Proof of Theorem nfsabg

Step	Hyp	Ref	Expression
1		nfsabg.1	. . . 4 ⊢ Ⅎ𝑥𝜑
2	1	nf5ri 2230	. . 3 ⊢ (𝜑 → ∀𝑥𝜑)
3	2	hbabg 2751	. 2 ⊢ (𝑧 ∈ {𝑦 ∣ 𝜑} → ∀𝑥 𝑧 ∈ {𝑦 ∣ 𝜑})
4	3	nf5i 2180	1 ⊢ Ⅎ𝑥 𝑧 ∈ {𝑦 ∣ 𝜑}

This proof depends on syntax axioms:  Ⅎwnf 1812   ∈ wcel 2142  {cab 2740

This proof depends on axioms:  ax-mp 5  ax-1 6  ax-2 7  ax-3 8  ax-gen 1824  ax-4 1838  ax-5 1939  ax-6 1996  ax-7 2037  ax-10 2175  ax-11 2191  ax-12 2212  ax-13 2403

This proof depends on definitions:  df-bi 210  df-an 401  df-or 861  df-tru 1572  df-ex 1809  df-nf 1813  df-sb 2096  df-clab 2741

This theorem is used by:  nfabg  2931