LINGUIST List 13.1379

Fri May 17 2002

Disc: Next to Last Posting/Falsifiability/Usefulness

Editor for this issue: Karen Milligan <karenlinguistlist.org>

Directory

1. Robert Whiting, Re: 13.1354, Disc: Falsifiability vs. Usefulness
2. Dan Everett, RE: 13.1376, Disc: Falsifiability vs. Usefulness

Message 1: Re: 13.1354, Disc: Falsifiability vs. Usefulness

On Wed, 15 May 2002 "H.M. Hubey" <hubeyhmail.montclair.edu> wrote

>A few comments on falsifiability.
>
>> From: Robert Whiting <whitingcc.helsinki.fi>
>> Subject: Re: 13.1334, Disc: Falsifiability vs. Usefulness
>>
>>
>> Falsifiability lies in the simple fact that a proposition and
>> its opposite (or P and ~P) cannot both be true at the same time
>> (although both may be false).
>
>That is certainly not possible. P + ~P =1 always. If P=0,
>and ~P=0, then we'd have P+~P=0 which is not possible.

This is only true of existential categorical propositions. Here
is the rule (sometimes known as the rule of existential falsity):

 If a categorical proposition implies but does not presuppose
 the existence of entities to which its subject or predicate
 or their contradictories apply, then it is false if any of
 these terms is empty.

What this means is that if X is presupposed to exist, then
of (1) X is P and (2) X is ~P, either (1) or (2) must be true and
the other false. But if X is not presupposed to exist then there
is the possiblity (3) X does not exist, and if (3) is true then
both (1) and (2) are false. (Unless, of course, (1) and (2) are
existential statments about X.)


Bob Whiting
whitingcc.helsinki.fi

Message 2: RE: 13.1376, Disc: Falsifiability vs. Usefulness

I have read Hubey's comments in 13.1376. To respond to them would
require recycling much of past discussion and a defense of Quine and
Hempel. However, I think that their original articles provide much
better justification for their positions than I can offer. I would
urge Hubey, therefore, to consult the original sources and rebut those
rather than argue against my citations of them, which results in
distortions of their views and the original points of the citations.

Dan Everett