Theorem 19.12OLD 1848

Description: Obsolete proof of 19.12 1847 as of 3-Jan-2018. (Contributed by NM, 5-Aug-1993.) (Proof modification is discouraged.) (New usage is discouraged.)

Assertion

Ref	Expression
19.12OLD	|- (E.xA.yph -> A.yE.xph)

Proof of Theorem 19.12OLD

Step	Hyp	Ref	Expression
1		hba1 1786	. . 3 |- (A.yph -> A.yA.yph)
2	1	hbex 1841	. 2 |- (E.xA.yph -> A.yE.xA.yph)
3		sp 1747	. . 3 |- (A.yph -> ph)
4	3	eximi 1576	. 2 |- (E.xA.yph -> E.xph)
5	2, 4	alrimih 1565	1 |- (E.xA.yph -> A.yE.xph)

Syntax hints:   -> wi 4  A.wal 1540  E.wex 1541

This theorem was proved from axioms:  ax-mp 5  ax-1 6  ax-2 7  ax-3 8  ax-gen 1546  ax-5 1557  ax-17 1616  ax-9 1654  ax-8 1675  ax-6 1729  ax-7 1734  ax-11 1746

This theorem depends on definitions:  df-bi 177  df-ex 1542

This theorem is referenced by: (None)