Ian Inkster

http://newsgroups.derkeiler.com/Archive/Talk/talk.origins/2009-08/msg01706.html

natural selection
COMPARE: "It is the influence of the environment, each generation, on which particular individuals of a population do\don't reproduce."

WITH: " The environment influences, each generation, which particular individuals of a population do\don't reproduce. "

The first is a definition of natural selection. It cannot be tautological, for it is but a mere noun-phrase, not even a statement. It is a reply to the question "what is natural selection" and it begins with "it is". So you certainly can't compare it with "What happens happens.", which is a statement.

The second is a statement, but it is not the theory itself, and so whether it is tautological doesn't matter. Call it tautological; it doesn't matter.

The theory itself is " The course of a species' evolution is influenced by natural selection, which is the influence of the environment, each generation, on which particular individuals of a population do\don't reproduce. "