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The whole point is that evolution is both a fact and a theory. I guess there were too many words for you in it.

[from a previous post by stremba] It IS a fact that the allele frequencies of the gene pools of populations of organisms change over time. That is the definition of the term evolution. Therefore evolution is a fact.

[my response] If one accepts your posit that the definition of evolution is only “change,” then I can hardly take exception to your assertion.

Is that your (shubi’s) definition of “evolution”… just change? If so, I cannot argue that it is fact. However, if this all there is to “evolution,” it explains nothing. It is the equivalent of saying “things change over time and therefore, things are different.” From this wonderful “theory” I can predict that “things” we find in the present will be different from “things” in the past and further that “things” that we may find in the future will different from “things” now. Any observer would come to same conclusion.

Facts are observations that are independent of the observer (ignoring the Heisenberg principle). Facts do not change. New facts may be discovered. However, if a “fact” supposedly changes, it wasn’t a fact to begin with.

Theories pose explanations for how facts came to exist as they are observed. Theories change. Each time a new fact is discovered, theories change to accommodate that fact. Each time a theory’s prediction is discovered to be incongruent with facts or less consistent than a competing theory’s predictions, the theory is changed or discarded.

So which is it? Is “evolution” a fact, and consequently, will never change? Alternately, is “evolution” a theory created to explain facts and will change as new facts are discovered or its predictions fail to align as well some potential, competing theory?

Unless you are playing games with semantics, it is one, or the other, not both.

So which is it? Is “evolution” a fact, and consequently, will never change? Alternately, is “evolution” a theory created to explain facts and will change as new facts are discovered or its predictions fail to align as well some potential, competing theory? Unless you are playing games with semantics, it is one, or the other, not both.

Unfortunately it is both, because the same word is used for two things. The fact of evolution is what we see in the fossil record, DNA comparisons with the phylogenetic tree, nested hierarchy, homologies, common inherited junk DNA across species boundaries etc etc. The evidence for this fact is considered absolutely overwhelming by biologists. Like the fact of gravity where we see objects all over our solar system obeying Newtons laws of motion as modified by Einsteins theory of relativity.

For gravity until recently there was no corresponding theory to go with the facts observed by Newton. Darwin's contribution was to both point out the fact of evolution, and explain it with a theory that was pretty good for the state of knowledge at that time; ie fundamentally correct as far as we can see, descent with modification through natural selection and geographic isolation. That theory has been revised in detail as more data has come in (eg Darwin knew nothing of the genetic mechanism whereby favourable changes are not diluted in the population, that contribution came from Mendel, and Mendel's work was further explained by our modern knowledge of DNA).

Biologists continue to debate the exact mechanisms of the theory a lot (as happens with all scientific theories as we continually improve our understanding of the universe), and sometimes creationists mischievously or mistakenly misinterpret such debates as implying lack of confidence in the fact of evolution.

I hope that makes the fact/theory issue a little clearer for you.