Re: Explaining explain

[John Mallinckrodt <ajmallinckro@CSUPomona.Edu>]

On Mon, 26 Jan 1998, LUDWIK KOWALSKI wrote:

> Yes, but the "truth" is a precondition of usefulness in science. How do we
> distinguish which reasonable conclusions are true and which are false?
> In the lab, you would probably say. Predictions based on the caloric theory 
> (sorry for this skeleton but I can not think of a better example right now) 
> are confirmed in the laboratory. Therefore it is a true and useful theory. 
> It does explain one domain of reality in human terms. You observe, you
> invent concepts (temperature, specific and latant heat) and you use these
> concepts to make good predictions. What else do you want? 

Ludwik,

You seem to understand that usefulness is enough.  Why muddy the water
with inappropriate and emotion laden words like "truth"?  Of course, in
order to be useful our theories must make accurate (enough) quantitative
predictions, but that doesn't make them "true." 
 
To "do" science, we must, I think, believe in the *existence* of an
objective reality, but there is no reason to think that we can ever know
its "true nature" and no difficulty that arises as a result as long as we
do not confuse ourselves and our students by using inappropriate words
like "truth" and "proof" in connection with our models.  My students
quickly learn that writing such things in their lab report summaries tends
to produce lots of green ink (my substitute for red) on their papers. 

John
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