I would pose this question to you. Scenario A: all the diversity of life formed via a process of unguided mutations followed by natural selection. Scenario B: all the diversity of life formed by a process of natural selection of mutations that are identical to those found in scenario A, but were caused by some guiding intelligence. What observable difference would there be between scenario A and scenario B? If there's no observable difference, then the question is not a scientific one. There is no way to test whether scenario A or B is the correct one. I would contend that there is no such test, and therefore that ID is not a scientific theory, at least the form of ID that does not deny that the primary mechanism leading to biodiversity is mutation and natural selection.
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