Theorem spsbeOLDOLD 2465

Description: Obsolete version of spsbe 2061 as of 7-Jul-2023. A specialization theorem. (Contributed by NM, 29-Jun-1993.) (Proof shortened by Wolf Lammen, 3-May-2018.) (Proof modification is discouraged.) (New usage is discouraged.)

Assertion

Ref	Expression
spsbeOLDOLD	⊢ ([𝑦 / 𝑥]𝜑 → ∃𝑥𝜑)

Proof of Theorem spsbeOLDOLD

Step	Hyp	Ref	Expression
1		sb1 2461	. 2 ⊢ ([𝑦 / 𝑥]𝜑 → ∃𝑥(𝑥 = 𝑦 ∧ 𝜑))
2		exsimpr 1851	. 2 ⊢ (∃𝑥(𝑥 = 𝑦 ∧ 𝜑) → ∃𝑥𝜑)
3	1, 2	syl 17	1 ⊢ ([𝑦 / 𝑥]𝜑 → ∃𝑥𝜑)

Syntax hints:   → wi 4   ∧ wa 396  ∃wex 1761  [wsb 2042

This theorem was proved from axioms:  ax-mp 5  ax-1 6  ax-2 7  ax-3 8  ax-gen 1777  ax-4 1791  ax-5 1888  ax-6 1947  ax-7 1992  ax-10 2112  ax-12 2141  ax-13 2344

This theorem depends on definitions:  df-bi 208  df-an 397  df-or 843  df-ex 1762  df-nf 1766  df-sb 2043

This theorem is referenced by: (None)