Talk:William of Soissons

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	This article was accepted from this draft on 18 December 2017 by reviewer DGG (talk · contribs).

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Astreven (talk) 09:13, 16 September 2018 (UTC)[reply]

Is there another proof?

The question remains if there is another proof. I don't think so.

Suppose a 'statement' follows logically from other statements or agreements.

Suppose an 'agreement' is more or less self evident in a community ( a civilization).

-(P & -P) is an agreement at least in Western Society. It is not a statement that follows from other statements or agreements. It is an agreement itself.

An agreement, like -(P&-P), cannot be proven logically. It works or it works not. See also L. Wittgenstein, Uber Gewissheit, Number 110 and further. Suhrkamp Verlag, 1982.

— Preceding unsigned comment added by Astreven (talk • contribs) 12:58, 16 September 2018 (UTC)[reply]

The appendix has a problem

Can anyone justify this statement?: "But (P &¬ P) can in this proof only be rejected if E is valid."

"¬(P &¬ P)" is an accepted tautology.

Daniel R. Grayson (talk) 12:56, 9 March 2020 (UTC)[reply]

The appendix was added by Astreven (talk). I propose to delete the appendix. Does anyone object?

Daniel R. Grayson (talk) 21:43, 18 May 2020 (UTC)[reply]