Theorem moor 2085

Description: "At most one" is still the case when a disjunct is removed. (Contributed by NM, 5-Apr-2004.)

Assertion

Ref	Expression
moor	|- ( E* x ( ph \/ ps ) -> E* x ph )

Proof of Theorem moor

Step	Hyp	Ref	Expression
1		orc 702	. 2 |- ( ph -> ( ph \/ ps ) )
2	1	moimi 2079	1 |- ( E* x ( ph \/ ps ) -> E* x ph )

Syntax hints:   -> wi 4   \/ wo 698   E*wmo 2015

This theorem was proved from axioms:  ax-mp 5  ax-1 6  ax-2 7  ax-ia1 105  ax-ia2 106  ax-ia3 107  ax-io 699  ax-5 1435  ax-7 1436  ax-gen 1437  ax-ie1 1481  ax-ie2 1482  ax-8 1492  ax-10 1493  ax-11 1494  ax-i12 1495  ax-bndl 1497  ax-4 1498  ax-17 1514  ax-i9 1518  ax-ial 1522  ax-i5r 1523

This theorem depends on definitions:  df-bi 116  df-nf 1449  df-sb 1751  df-eu 2017  df-mo 2018

This theorem is referenced by:  mooran2  2087