[Petrosius]

You hit the nail on the head. The debate about Evolution often centers around whether is should be called a proven fact, a theory or an hypothesis. In reality it is none of these. Evolution tries to explain how the various life forms arose. By the very nature of the subject, these events are unrepeatable and closed to observation. There is no experiment that can produce a vertebrate from an invertebrate. Even if it were theoretically possible, the millions of years that Evolution postulates would make it unobservable. Thus, not being subject to experimentation and so not being disprovable, Evolution is logically no more than conjecture. This conjecture might have sound scientific reasons behind it but it still does not rise above conjecture. Contrary to the desires of its proponents, Evolution (the explanation of why there arose new life forms in the past) is not an empirical science.

[bobdsmith]

Thus, not being subject to experimentation and so not being disprovable, Evolution is logically no more than conjecture.

Im sorry but that's wrong. Evolution is subject to experimentation and being potentially disprovable. Every fossil unearthed tests the theory and could potentially disprove it. Every genome sequenced is a test. Every organism studied is a test. It is empirical science.

[supercat]

There is no experiment that can produce a vertebrate from an invertebrate.

And even if such a result could be proven experimentally, that would not prove that vertibrates were produced from invertebrates by the same means as was used in the experiment.

To use an archaeological analogy, there are various theories as to how the pyramids were built. The supporters of some of these theories have attempted to produce blocks similar to those in the pyramids, using materials that would have been available at the time the pyramids were constructed. Some of these supporters, from what I understand, have succeeded pretty well.

Nonetheless, the most these people can really hope to do is show that the pyramids could have been constructed via the method they suggest. They can not prove that the pyramids were in fact constructed that way.