Subject: Re: [lojban] Trivalent logic [was: Re: the logical language]

From: John Cowan <[email-masked]>
Date: Mon, 19 Jun 2000 12:15:16 -0400

Robin wrote:

> For example, let's say we give the statement "Foobars like to be
> globbed" a truth value of 0.8 .

The trouble with your reanalysis is that we can do it for ordinary truth
values too. Consider "snow is white" (true).

> I would interpret this as either
> 
>  "80% of foobars like to be globbed"

"100% of snow is white."

> or
> 
> "There is 80% certainty that all foobars like to be globbed"

It is certain that snow is white.

> or
> 
> "A typical foobar, if asked to express its liking for being globbed on
> a scale from 0 to 1, would give an answer of 0.8"

?When we ask snow whether it is white, it replies "Yes".
?When we ask anyone whether snow is white, he/she replies "Yes".

We can get rid of truth, at least singly, by employing quotation instead:
snow is white if and only if "snow is white" is true. Unfortunately
this does not extend to quantified uses of it: (Ex) (x is true) cannot
be disposed of in such a way, and no more can (Ex) (x is 80% true).

-- 

Schlingt dreifach einen Kreis um dies! || John Cowan <[email-masked]>
Schliesst euer Aug vor heiliger Schau, || http://www.reutershealth.com
Denn er genoss vom Honig-Tau, || http://www.ccil.org/~cowan
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