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From: laura@l5.uucp (Laura Creighton)
Newsgroups: net.philosophy
Subject: Re: Consistency Again
Message-ID: <244@l5.uucp>
Date: Tue, 5-Nov-85 13:22:54 EST
Article-I.D.: l5.244
Posted: Tue Nov  5 13:22:54 1985
Date-Received: Fri, 8-Nov-85 05:55:01 EST
References: <2479@sjuvax.UUCP>
Reply-To: laura@l5.UUCP (Laura Creighton)
Distribution: net
Organization: Nebula Consultants in San Francisco
Lines: 89

Todd understand me very well.  I have never been described as a
coherentist theorest before, but the shoe seems to fit.  There are
a few things that I would like to elucidate a bit more...

>I think it is fair to describe Laura's position as a "coherence
>theory of truth."  For a coherentist theorist, truth is only definable
>within sets of statements, I take it.  

Pretty well.  Of course, the process of dividing things into statements
is to some extent a-priori, and so the statements that result are
to some extent artificial.  Truth is only definable within beliefs,
which are commonly expressed as statements (statements of beliefs).

>Individual statements would lack truth values.  

I am not sure that this is strictly so.  It is impossible to determine
the truth of a statement independent of other beliefs, but it is
easy to determine that the statement ``Laura is 7 feet tall'' is
false.  At that point, I would say that it is quite correct to assign a
truth value of false to that statement.  Note that it is impossible to
arrive at this statement without some beliefs in the accuracy of your
ability to measure.

There are certain statements which cannot be assigned a truth value, of
course. Consider the pair:

	The following sentence is true.
	The preceeding senetence is false.

To consider them individually would be a mistake.  To consider them
in reference to each other yeilds ambiguity.  You cannot assign truth
values to either of them.

>A false statement, on this view, would be one that
>would make a contradiction derivable from the set, that would not have
>been derivable had that statement not been added.

This is dead-on.

>For purposes of analysis, regard someone's belief system as the set of
>propositions to which that person would assent.  When contradictions
>become apparent, a rational individual rejects the smallest possible
>number of propositions required to remove the inconsistency.  This
>ranking process is necessary to keep the coherence theory from
>licensing the rejection of tremendous portions of the belief system
>for the sake of isolated incongruities.  Nothing said so far requires
>that truth be defined as a relation between statements and
>mind-independent reality.

I think that I am defining truth as a relationship which beliefs have
taken as a whole.  Statements of belief which are called ``true'' are
ways of expressing  memebers of the set of beliefs which have the
truth relationship.

Also, the ranking of true beliefs in a rational person is more
complicated than what you have outlined.  At some point it would be
simpler to reject the evidence of your own eyes and remove the
smallest number of propositions that keeps you inconsistent with
other people.  A rational person does this sometimes, but often
should tenatiously hang onto their beliefs because it is the other
people who are mistaken.

Observational errors are common.  Somebody may have a set of beliefs
that are consistent with what they believe they observed but not consistent
with what happened because they made an observational error.  For this
reason, most rational people have a ``bullshit index'' that they apply
to all new evidence -- how likely is it that this new bit of information
is bogus?

>But I am not clear about what Laura means by "facts", since these, on
>the face of it, appear to be observer-independent Truths.  If that is
>the case, then the inconsistency is reintroduced after all.

No, a fact is a presumed-true.  it is a statement that I believe is true.
(Once I disbelieve it, it is no longer a fact).  I think that I use
``fact'' where you would use ``true statement'' or ``true proposition''.

A new fact is a belief that you have to integrate into your set of beliefs.
This will often entail rejecting things which yesterday you would have
called facts, and today which you would call ``mistaken beliefs''.

-- 
Help beautify the world. I am writing a book called *How To Write Portable C
Programs*.  Send me anything that you would like to find in such a book when
it appears in your bookstores. Get your name mentioned in the credits. 

Laura Creighton		
sun!l5!laura		(that is ell-five, not fifteen)
l5!laura@lll-crg.arpa