Evolution as such is not a theory. Science regards it as fact. Where theory comes into play is in describing how it works, and there are quite a few theories of how evolution works depending on what aspect of evolution is being addressed. "Theory of evolution" most often comes into play as a synonym for evolution. It is not. This misnomer is typically used by creationists who employ it as a way to demote evolution from its status as fact to the level of a theoretical construct in the minds of the unwitting. Whether this is done out of ignorance or a tactical ploy seems to depend on the resolve of its proponent. Informed creationists, often its spokesmen, who know better purposely use it to denigrate evolution. (While they don't accept evolution as factual, they know science does.) The rest of the creationist community seem to be unwitting sheep who simply don't know any better. They truly believe evolution is no more than a theory. Unfortunately, aside from creationists, "theory of evolution" has been mistakenly picked up by others as a valid moniker for evolution. If you're prone to use it, don't.
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