> >> I then examine "not A" to see whether it's universally false. If so > >> the universal truth of "A" is demonstrated because the tautological > >> proposition "A, not A" is exhaustive of all possibilities for truth. > > > >If you claim that you can prove "A" this way then you are using the law > >of the excluded middle, which you said you did not assume to be valid.. > > I don't assume the law of the excluded middle to be valid in general > expecially where compound predicates are involved. It's actually only > valid in the one instance where single universal predicates are used.
Then you are assuming that some limited version of the law of the excluded middle is valid. In any case, you cannot get your desired result without SOME assumption. > > >> >As usual, I request an example of Zick's alleged assumption used to > >> >prove itself true. > >> > >> Well perhaps the general claim is too obscure. > >> > >> >And as usual, Zick will not provide one. > >> > >> See the example of the reasoning involved above. The initial > >> assumption "A" is just an assumption and does not and cannot be used > >> to prove itself. That should go without saying. However we can > >> recognize the fact of self contradiction in "not A" if it is present > >> and if present we can assume "not A" is universally false from that > >> and infer that "A" must be universally true because its tautologically > >> exhaustively alternative is always false. > > > >If you claim that you can prove "A" this way then you are using the law > >of the excluded middle, which you said you did not assume to be valid.. > >> > >> > >> The fact of universal self contradiction is not necessarily obvious in > >> examples like "not A" because there is nothing apparent in the example > >> to indicate it. But in an example like "not not" the fact of self > >> contradiction is obvious > > > > Not to me, as I have no idea what "not not" is saying that could be > >interpreted as self contradictory. > > You don't see the "contradiction of contradiction" as self > contradictory? My but you are uncommonly slow.
I do not see double negation as anything but affirmation. > > >The only sensible interpretation I can think of is that for every > >proposition A, "not not" returns the proposition "not(notA))". > >And this interpretation confounds Zick's argument. > > And how about the proposition "not(not)"? What does that return?
As "not" is a logical operator, it has no meaning until it operates on something, and like numerical negation, doubling it cancels it. > > >> and we infer with confidence that "not" must > >> be absolutely and universally true because its tautological > >> alternative "not not" is obviously and necessarily self contradictory > >> and hence false and the tautological combination (not, "not not") > >> exhausts all possibilities for truth. > > > > > >Zick's "inference with confidence" fails to inspire me with the least > >iota of confidence that "not not" is anything but doubletalk. > > All self contradiction is doubletalk.
Certainly all ZIck's talk tends to be self contradictory doubletalk