Theorem spimevw 1999

Description: Existential introduction, using implicit substitution. This is to spimew 1976 what spimvw 2000 is to spimw 1975. Version of spimev 2392 and spimefv 2194 with an additional disjoint variable condition, using only Tarski's FOL axiom schemes. (Contributed by NM, 10-Jan-1993.) (Revised by BJ, 17-Mar-2020.)

Hypothesis

Ref	Expression
spimevw.1	⊢ (𝑥 = 𝑦 → (𝜑 → 𝜓))

Assertion

Ref	Expression
spimevw	⊢ (𝜑 → ∃𝑥𝜓)

Distinct variable groups:   𝑥,𝑦   𝜑,𝑥

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

Proof of Theorem spimevw

Step	Hyp	Ref	Expression
1		ax-5 1914	. 2 ⊢ (𝜑 → ∀𝑥𝜑)
2		spimevw.1	. 2 ⊢ (𝑥 = 𝑦 → (𝜑 → 𝜓))
3	1, 2	spimew 1976	1 ⊢ (𝜑 → ∃𝑥𝜓)

Syntax hints:   → wi 4  ∃wex 1783

This theorem was proved from axioms:  ax-mp 5  ax-1 6  ax-2 7  ax-3 8  ax-gen 1799  ax-4 1813  ax-5 1914  ax-6 1972

This theorem depends on definitions:  df-bi 206  df-ex 1784

This theorem is referenced by:  dtru  5288  zfpair  5339  fvn0ssdmfun  6934  bj-dtru  34926  sn-dtru  40116  refimssco  41104  rlimdmafv  44556  rlimdmafv2  44637  elsprel  44815