throopw@rtp47.UUCP (Wayne Throop) (05/23/85)
There have been several postings to the effect that evolution predicts nothing by virtue of predicting everything. So summarize, quoting Paul DuBois on what evolution says organisms will "do": > They'll get more complex. Or they'll get simpler. Or > they'll stay the same. Some prediction. > Or did you have something else in mind? Examining these seperate predictions, we find that indeed evolution predicts complex organisms will develop from simple ones, if the environment gives advantage to complexity. Similarly, the prediction is that organisms will "get simpler" when the environment gives advantage to simplicity. And, oddly enough, they will stay the same when the environment gives advantage to stasis (or gives no advantage for changing). Therefore I think that the problem that Paul points out is a non-existant one. Evolution predicts that species will evolve in response to the environment. Paul's objection is similar to saying that Newton's laws are non-predictive because they predict that objects will "Proceed in straight lines. Or they'll curve. Or they'll stay still. Or they'll accelerate. Some prediction." Note that even when the environment is known to some degree, evolution can give ambiguous predictions in complex, real-world cases, for about the same reason that simple application of Newston's laws aren't of much help with three-or-more body problems in astronomy. In each case the "environment" is too complex for simple analysis. Evolutionary predictions as stated by Paul seem arbitrary, but seem quite reasonable to me when qualified by the addition that they are predictions of response to environmental change by natural selection. As I see it, the claim that evolution is not predictive because it predicts everything is not valid. Or did Paul have something else in mind? -- Wayne Throop at Data General, RTP, NC <the-known-world>!mcnc!rti-sel!rtp47!throopw
rlr@pyuxd.UUCP (Arthur Pewtey) (06/01/85)
> Therefore I think that the problem that Paul points out is a > non-existant one. Evolution predicts that species will evolve in > response to the environment. Paul's objection is similar to saying that > Newton's laws are non-predictive because they predict that objects will > "Proceed in straight lines. Or they'll curve. Or they'll stay > still. Or they'll accelerate. Some prediction." [WAYNE THROOP] Note that creationists are basically religionist in nature ["YOU'RE KIDDING?" -ED.], and that if a system of prediction doesn't "work" for them, resulting in the kinds of answers they want about the world, they out of hand reject it, preferring their own system that does provide the kind of answers they want, regardless of their accuracy. -- Anything's possible, but only a few things actually happen. Rich Rosen pyuxd!rlr