Theorem ax46to6 1060

Description: Re-derivation of ax-6o 1019 from ax46 1058. Only propositional calculus is used for the re-derivation. (Contributed by Scott Fenton, 12-Sep-2005.)

Assertion

Ref	Expression
ax46to6	|- (-. A.x -. A.xph -> ph)

Proof of Theorem ax46to6

Step	Hyp	Ref	Expression
1		pm2.21 79	. 2 |- (-. A.x -. A.xph -> (A.x -. A.xph -> A.xph))
2		ax46 1058	. 2 |- ((A.x -. A.xph -> A.xph) -> ph)
3	1, 2	syl 10	1 |- (-. A.x -. A.xph -> ph)

Syntax hints:  -. wn 2   -> wi 3  A.wal 995

This theorem was proved from axioms:  ax-1 4  ax-2 5  ax-3 6  ax-mp 7  ax-4 1014  ax-6o 1019

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