Theorem sbievw 2094

Description: Conversion of implicit substitution to explicit substitution. Version of sbie 2501 and sbiev 2313 with more disjoint variable conditions, requiring fewer axioms. (Contributed by NM, 30-Jun-1994.) (Revised by BJ, 18-Jul-2023.) (Proof shortened by SN, 24-Aug-2025.)

Hypothesis

Ref	Expression
sbievw.is	⊢ (𝑥 = 𝑦 → (𝜑 ↔ 𝜓))

Assertion

Ref	Expression
sbievw	⊢ ([𝑦 / 𝑥]𝜑 ↔ 𝜓)

Distinct variable groups:   𝑥,𝑦   𝜓,𝑥

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

Proof of Theorem sbievw

Step	Hyp	Ref	Expression
1		sbievw.is	. . 3 ⊢ (𝑥 = 𝑦 → (𝜑 ↔ 𝜓))
2	1	sbbiiev 2093	. 2 ⊢ ([𝑦 / 𝑥]𝜑 ↔ [𝑦 / 𝑥]𝜓)
3		sbv 2089	. 2 ⊢ ([𝑦 / 𝑥]𝜓 ↔ 𝜓)
4	2, 3	bitri 275	1 ⊢ ([𝑦 / 𝑥]𝜑 ↔ 𝜓)

Syntax hints:   → wi 4   ↔ wb 206  [wsb 2065

This theorem was proved from axioms:  ax-mp 5  ax-1 6  ax-2 7  ax-3 8  ax-gen 1795  ax-4 1809  ax-5 1910  ax-6 1967  ax-7 2008

This theorem depends on definitions:  df-bi 207  df-an 396  df-ex 1780  df-sb 2066

This theorem is referenced by:  sbiedvw  2096  2sbievw  2097  sbievw2  2099  cbvsbv  2101  sbco4  2103  sbid2vw  2260  2mosOLD  2644  eqabbw  2803  sbralie  3328  sbralieALT  3329  rabrabi  3428  elabgw  3647  ralab  3667  sbcco2  3783  sbcie2g  3797  csbied  3901  dfss2  3935  unabw  4273  notabw  4279  ab0w  4345  ab0orv  4349  2reu8i  47118  ichcircshi  47459