Theorem psseq2i 3593

Description: An equality inference for the proper subclass relationship. (Contributed by NM, 9-Jun-2004.)

Hypothesis

Ref	Expression
psseq1i.1

Assertion

Ref	Expression
psseq2i

Proof of Theorem psseq2i

Step	Hyp	Ref	Expression
1		psseq1i.1	. 2
2		psseq2 3591	. 2
3	1, 2	ax-mp 5	1

Syntax hints:  <->wb 184  =wceq 1395  C.wpss 3476

This theorem is referenced by:  psseq12i  3594  disjpss  3877  infeq5i  8074

This theorem was proved from axioms:  ax-mp 5  ax-1 6  ax-2 7  ax-3 8  ax-gen 1618  ax-4 1631  ax-5 1704  ax-6 1747  ax-7 1790  ax-10 1837  ax-11 1842  ax-12 1854  ax-13 1999  ax-ext 2435

This theorem depends on definitions:  df-bi 185  df-an 371  df-tru 1398  df-ex 1613  df-nf 1617  df-sb 1740  df-clab 2443  df-cleq 2449  df-clel 2452  df-ne 2654  df-in 3482  df-ss 3489  df-pss 3491