> a) Define "truth"? ...
>
> b) Can you then show me that this truth is not relative but objective or
> at least universal? Not in terms of particulars but in universal
> scope?
Scientists are far too vulgar to deal with this. You want the philosophy department.
> c) How do you define "superior"? Do you really think that astronomy is
> superior to astrology (for explaining the nature of the universe) in
> every sense? How do you expect to demonstrate that conclusively?
For the first part, I defer to Dwayne. Regarding its conclusiveness, you don't. See the end paragraphs of <http://www.talkorigins.org/faqs/evolution-fact.html>.
> d) What does superiority have to do with truth? Ptolemaic system of
> planetary motion were probably superior to whatever it replaced. Does
> that make it "true"? Is Reimann geometry true?
See a) and b).
> e) What is meant by "validity" (of science)? Valid in what sense? In
> representing "truth"? In being "superior"? Or just in the mundane
> sense of being more reliable than a few other systems?
Totally mundane, in a tiresomely persnickity way.
> f) Can you define "science"?
You already did. Back during the alternative medicine thread, you suggested what you described as an alternative to science:
"Here, spelled out, off the top of my head, is one alternative non-scientific means of selecting possible treatment: (a) use a conception of the world and its components, (b) choose theories (in this case treatments) in the order of least inconsistency with this conception, (c) use the conception to device tests on the efficiency of the theories (treatments), (d) evaluate the test results to ascertain a possible best candidate, (e) apply the best candidate to the world and (ii) monitor its effectiveness, (f) either as a result of e(ii) or because you have the energy or time, evaluate in reverse order other theories, (g) use the theories and findings to revise your conception of the world, (h) design counter-tests that challenge your conception and your theories."
I read this carefully too late to reply at the time, but this is a superb (if perhaps idealistic) description of the scientific method -- you can boil it down quite cleanly to "guess and test". You went on to note that you observe your toddler performing the above, but you wouldn't call him a scientist. Why not? The authors of _The Scientist in the Crib_ made a thesis out of saying just the opposite.
That you present the above as an alternative to science suggests that you're persuing the wrong whale.
> g) When we abandon one system of explanation for another because the
> latter is more parsimonious or more elegant (easier to work with,
> etc), is this because the latter is more "true"? Or is it just a
> matter of "taste? (a preference for parsimony, elegance, etc).
Replace "true" with "closer to observation" and you have yourself an interesting question that I won't address since that doesn't seem to be what we're discussing. :-)
-- Andy