Theorem repizf 4002

Description: Axiom of Replacement. Axiom 7' of [Crosilla], p. "Axioms of CZF and IZF" (with unnecessary quantifier removed). In our context this is not an axiom, but a theorem proved from ax-coll 4001. It is identical to zfrep6 4003 except for the choice of a freeness hypothesis rather than a distinct variable constraint between b and ph. (Contributed by Jim Kingdon, 23-Aug-2018.)

Hypothesis

Ref	Expression
ax-coll.1	|- F/ b ph

Assertion

Ref	Expression
repizf	|- ( A. x e. a E! y ph -> E. b A. x e. a E. y e. b ph )

Distinct variable group:   x, y, a, b

Allowed substitution hints:   ph( x, y, a, b)

Proof of Theorem repizf

Step	Hyp	Ref	Expression
1		euex 2003	. . 3 |- ( E! y ph -> E. y ph )
2	1	ralimi 2467	. 2 |- ( A. x e. a E! y ph -> A. x e. a E. y ph )
3		ax-coll.1	. . 3 |- F/ b ph
4	3	ax-coll 4001	. 2 |- ( A. x e. a E. y ph -> E. b A. x e. a E. y e. b ph )
5	2, 4	syl 14	1 |- ( A. x e. a E! y ph -> E. b A. x e. a E. y e. b ph )

Syntax hints:   -> wi 4   F/wnf 1417   E.wex 1449   E!weu 1973   A.wral 2388   E.wrex 2389

This theorem was proved from axioms:  ax-1 5  ax-2 6  ax-mp 7  ax-ia1 105  ax-ia2 106  ax-ia3 107  ax-io 681  ax-5 1404  ax-7 1405  ax-gen 1406  ax-ie1 1450  ax-ie2 1451  ax-8 1463  ax-10 1464  ax-11 1465  ax-i12 1466  ax-bndl 1467  ax-4 1468  ax-17 1487  ax-i9 1491  ax-ial 1495  ax-i5r 1496  ax-coll 4001

This theorem depends on definitions:  df-bi 116  df-nf 1418  df-sb 1717  df-eu 1976  df-ral 2393

This theorem is referenced by:  zfrep6  4003  repizf2  4044