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Theorem ax6o 1323
Description: Show that the original axiom ax-6o 1324 can be derived from ax-6 1303 and others. See ax6 1325 for the rederivation of ax-6 1303 from ax-6o 1324.

This theorem should not be referenced in any proof. Instead, use ax-6o 1324 below so that uses of ax-6o 1324 can be more easily identified.

Assertion
Ref Expression
ax6o |- (-. A.x -. A.xph -> ph)

Proof of Theorem ax6o
StepHypRef Expression
1 ax-4 1319 . 2 |- (A.xph -> ph)
2 ax-6 1303 . 2 |- (-. A.xph -> A.x -. A.xph)
31, 2nsyl4 135 1 |- (-. A.x -. A.xph -> ph)
Colors of variables: wff set class
Syntax hints:  -. wn 2   -> wi 3  A.wal 1296
This theorem was proved from axioms:  ax-1 4  ax-2 5  ax-3 6  ax-mp 7  ax-6 1303  ax-4 1319
Copyright terms: Public domain