No amount of observations of complicated things coming from natural processes will ever prove that complicated things never came from non-natural processes.
Of course not. But this isn't the point being advanced by Mod. ID does not say that an agent may have been involved in the evolution of life - this is really the basis of theistic evolution. ID states that life is too complex to have developed solely by evolution and that the interaction of an agent is *necessary*. Every evololutionary pathway discovered and understood is yet another nail in the coffin of ID. Every time an IDer presents the smoking-gun evidence of a structure inexplicable by evolution, the possible evolutionary pathways are examined and demonstrated plausible - and ID dies another death.
It is true that all it takes is one example of a structure that cannot possibly have evolved, and ID has won. But we are esentially at the point where the only possible such structures would be of the form "(c) Yhwh 4150 BC" etched into our DNA...
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