Theorem nfcsb 3936

Description: Bound-variable hypothesis builder for substitution into a class. Usage of this theorem is discouraged because it depends on ax-13 2375. Use the weaker nfcsbw 3935 when possible. (Contributed by Mario Carneiro, 12-Oct-2016.) (New usage is discouraged.)

Hypotheses

Ref	Expression
nfcsb.1	⊢ Ⅎ𝑥𝐴
nfcsb.2	⊢ Ⅎ𝑥𝐵

Assertion

Ref	Expression
nfcsb	⊢ Ⅎ𝑥⦋𝐴 / 𝑦⦌𝐵

Proof of Theorem nfcsb

Step	Hyp	Ref	Expression
1		nftru 1801	. . 3 ⊢ Ⅎ𝑦⊤
2		nfcsb.1	. . . 4 ⊢ Ⅎ𝑥𝐴
3	2	a1i 11	. . 3 ⊢ (⊤ → Ⅎ𝑥𝐴)
4		nfcsb.2	. . . 4 ⊢ Ⅎ𝑥𝐵
5	4	a1i 11	. . 3 ⊢ (⊤ → Ⅎ𝑥𝐵)
6	1, 3, 5	nfcsbd 3934	. 2 ⊢ (⊤ → Ⅎ𝑥⦋𝐴 / 𝑦⦌𝐵)
7	6	mptru 1544	1 ⊢ Ⅎ𝑥⦋𝐴 / 𝑦⦌𝐵

Syntax hints:  ⊤wtru 1538  Ⅎwnfc 2888  ⦋csb 3908

This theorem was proved from axioms:  ax-mp 5  ax-1 6  ax-2 7  ax-3 8  ax-gen 1792  ax-4 1806  ax-5 1908  ax-6 1965  ax-7 2005  ax-8 2108  ax-9 2116  ax-10 2139  ax-11 2155  ax-12 2175  ax-13 2375  ax-ext 2706

This theorem depends on definitions:  df-bi 207  df-an 396  df-or 848  df-tru 1540  df-ex 1777  df-nf 1781  df-sb 2063  df-clab 2713  df-cleq 2727  df-clel 2814  df-nfc 2890  df-sbc 3792  df-csb 3909

This theorem is referenced by:  cbvralcsf  3953  cbvreucsf  3955  cbvrabcsf  3956  elfvmptrab1  7044  elovmporab1  7681