Re: What are "principles" in science?

[Jack Uretsky <jlu@HEP.ANL.GOV>]

Hi all-
        I don't know anybody involved in the active pursuit of physics,
biology, chemistry or the like who would support this so-called
"traditional picture".  Do you have some support for your
characterization?  And why is it important to have such categories?

Feynman (III-13-1), in describing the conduction of electrons in
chrystals, writes: "The laws of give the followwing results."  He then
describes the result of a calculation.

Would tthe meeaning be any less clear if he had said "the principles of
quantum mechanics', or "the theory of quantum mechanics", or "a quantum
mechanical calculation"?  I note that he does not discuss such categories
anywhere in his lectures.

I have noted that beginning elementary and high school teachers, when
unsure of their subject matter, tend to emphasize names and definitions.
I think that i9 because the leaqrning of names and definitions is the
easiest kind of teaching that can be readily measured.  Standardized tests
are easy to construct for such purposes.

I suggest that the best answer to the question that starte this thread
is:  "Call it what you want; a rose by any other name sould smell as
sweet."  On second thought, I would not compare the quotation under
discussion with "a rose."
                                        Regards,
                                                Jack




On Mon, 7 Jun 2004, Mark Sylvester wrote:

> I too would prefer to call the stated "principle" a theory or a model.
>
> In all this terminology, as others have pointed out, much is a matter of
> definition, but there an important distinction to be made, at least within
> the traditional picture of how science proceeds: the empirical law on the
> one hand, and the theory/model on the other.
>
> The empirical law comes from observation, by inductive reasoning. We may
> take the gas laws as typical. The theory/model postulates unobserved
> entities and explains the empirical laws by deductive reasoning. The
> kinetic theory of gases would be the corresponding example. The theory does
> not come (directly) from observation.
>
> I am aware of the many qualifications that apply to this picture, but I
> find it immensely helpful.
>
> Mark
>
> At 13:59 07/06/04 -0400, you wrote:
> > What does the quoted principle explain?
> >
> > On Monday, Jun 7, 2004, at 10:11 America/New_York, Robert Cohen wrote:
> >
> > > > "A  PRINCIPLE TO REMEMBER. In a chemical
> > > > change the atoms in substances are rearranged
> > > > to make one or more new substances. The result
> > > > is a change in composition."
> > > >
> > > > Would it be appropriate to replace the word
> > > > PRINCIPLE by the word LAW?
> > >
> > > Although there is no hard and fast rule concerning the use of the
> > > terms,
> > > to me it sounds like an explanation and, as such, has more in common
> > > with a theory than a law.
> > >
> > > ____________________________________________________
> > > Robert Cohen; 570-422-3428; www.esu.edu/~bbq
> > > East Stroudsburg University; E. Stroudsburg, PA 18301
>
> Mark Sylvester
> UWCAd
> Duino Trieste Italy

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