One of my quirkier philosophical views is that the most pressing question in metaphysics, and perhaps all of philosophy, is how to distinguish between disjunctive and non-disjunctive predicates in the special sciences. This might look like a relatively technical problem of no interest to anyone. But I suspect that the question is important to all sorts of issues, as well as being one of those unhappy problems that no one seems to even have a beginning of a solution to. One of the issues that it’s important to was raised by “Brad DeLong”:http://delong.typepad.com/sdj/2007/01/the_meddling_id.html yesterday. He was wondering why John Campbell might accept the following two claims.
* There is an important and unbridgeable gulf between our notions of physical causation and our notions of psychological causation.
* Martian physicists–intelligences vast, cool, and unsympathetic with no notions of human psychology or psychological causation–could not understand why, could not put their finger on physical variables and factors explaining why, the fifty or so of us assemble in the Seaborg Room Monday at lunch time during the spring semester.
I don’t know why Campbell accepts these claims. And I certainly don’t want to accept them. But I do know of one good reason to accept them, one that worries me no end some days. The short version involves the conjunction of the following two claims.
* Understanding a phenomenon involves being able to explain it in relatively broad, but non-disjunctive, terms.
* Just what terms are non-disjunctive might not be knowable to someone who only knows what the Martian physicists know, namely the microphysics of the universe.
The long version is below the fold. (This is cross-posted to CT, so I’ve filled in more of the background than I usually would here.)
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