Yes, that was sort of the point - you can't make a function for "is a Turing machine" that works in all cases, and you can't make a "is a non-person" function that works in all case either. Further, the set of things you can rule out with 100% certainty is to small to be useful.
Don't see how that relates to my suggestion of a probabilistic answer though. Has anyone proven that you can't make a statistically valid statement about the "Is a Turing machine" question?
Today's post, Nonperson Predicates was originally published on 27 December 2008. A summary (taken from the LW wiki):
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