Re: [asa] YEC--What can we offer them?

Randy wrote:

"By the way...I ended up claiming that, as far as I could tell,
there has been no case where a scientific theory which has been validated by
data from many independent sources and which is accepted as consensus by the
mainstream community, has been later invalidated. I'd love to hear of any
examples that any of you might think of."

I wrote earlier that QM and plate tectonics were theories that had
invalidated earlier accepted theories, but "Newton was not wrong, but his
theory lacked generality." On second thought I now claim that Newton also
was wrong, that his theory of gravitation was invalidated by general
relativity. The reason his theory is wrong is the same reason the others
were wrong: they were based on the wrong models.

Let me explain: What does it mean for a scientific theory to be invalid or
wrong? Globally all theories are wrong because none is absolutely true.
What we mean when we say a theory is correct is that it is the best theory
currently available. When we say a theory is the best available, we mean
that we prefer its underlying models over those of any competing theory,
because those models give results in some way superior to results of
competing models.

So the underlying models--or paradigms, as I've been calling them--are
absolutely decisive in any effort to determine whether or not a theory is
wrong. While a theory based on the wrong models may sometimes give good
quantitative answers, from the point of view of theoretical science the
underlying models are more important than the answers (within limits, of
course). Even absurd theories can sometimes give good answers.

Newton's paradigm assumed space-time was absolute and independent of masses
within, and it assumed masses fall towards one another because of a force
between them acting at a distance. General relativity, the better theory,
says those assumptions are not true. Therefore Newton's theory is wrong
because it's based on invalid models. Even though general relativity gives
Newton's formalism in a limiting case, from the point of view of scientific
theory it doesn't make Newton's theory right.

Science advances in a sort of bootstrap fashion by replacing current models
with new models. In the process the replaced models become obsolete as
theory--in other words, wrong.

So I'd revise Randy's claim to read as follows: Scientific theories go
where experiments and human minds lead. In no case have scientists gone
back to an old theory once data and theorists made it clear there was a
better theory. (Exception: Sometimes an old theory still has pedagogical or
computational uses.)

Of course, this may well not be the kind of thing Randy wanted to say!

Don

----- Original Message -----
  From: Don Winterstein<mailto:dfwinterstein@msn.com>
  To: asa<mailto:asa@calvin.edu> ;
Dawsonzhu@aol.com<mailto:Dawsonzhu@aol.com>
  Cc: Randy Isaac<mailto:randyisaac@comcast.net>
  Sent: Wednesday, July 04, 2007 11:08 PM
  Subject: Re: [asa] YEC--What can we offer them?

  Wayne wrote:
  "I don't really see things like relativity theory being
  as much a paradigm shift as an extension of the limiting
  case of Newton's law of gravitation."

  Newton's gravity is rather the low-velocity limit of general relativity.
And the jump to general relativity constitutes a paradigm shift if there
ever was one: With Newton, there's an attractive force between objects at a
distance that determines relative trajectories; with Einstein, four-space
geometry determines trajectories, where the shape of the four-space depends
on the masses within it. There's no attractive force; objects simply follow
their geodesics in space-time.

  General relativity differs radically from Newton in its way of looking at
space, time and motion. The practical consequences are minuscule compared
with the magnitude of the paradigm shift behind them! Newton was not wrong,
but his theory lacked generality.

  Quantum mechanics revealed that entities at micro-scale behave nothing
like entities at macro-scale. So QM also introduced a paradigm shift,
because the general assumption had been that objects should behave similarly
at all scales.

  In this case physicists were wrong (their "theories were invalidated")
because they assumed objects should behave similarly at all scales.

  Earth scientists early last century were wrong about plate tectonics
because they (often vociferously) derided the idea of continental drift.

  In both these cases--QM and plate tectonics--experimental data shoved
scientists by the seat of the pants kicking and screaming into new
paradigms.

  Therefore I'd revise Randy's claim as follows: Scientific theories go
where experiments lead. In no case have scientists gone back to an old
theory once data and theorists made it clear there was a better theory.
(Exception: Sometimes an old theory still has pedagogical or computational
uses.)

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Received on Sat Jul 7 01:49:12 2007