[Logiweb] axiom A6

[Klaus Ebbe Grue]

Hi Kasper,

> I would like to ask Klaus why axiom A6 is "missing" from the peano page.
> It would have been usefull while I was proving Lemma 3.2g.

Because Mendelsons system S does not include A6.

Mendelsons system S does not include A6 because A6 can be proved from the 
other axioms. By the way, Mendelsons system S does not include A7 either, 
and for the same reason.

Klaus