yesterday's blogtime was devoted to helping my sister put together packets of things for the voters of maricopa county, AZ. today, in light of this, and the difficulty of the subject matter i'm giving myself an hour.
several months ago i left hanging a post about causation, that claimed to be part one of a two part series. the gist of the thing (part one) was this: even if you know the whole story of how something came to pass, you don't yet have a way of establishing what caused it. run the tape backwards-- watch the bridge resurrect, uncollapse, in excruciating detail-- watch the cars and boats slide backward underneath and over it, and days become nights become days, the rain stopping, and the rain starting again-- watch the thing unravel back to the first moment a sleepy engineer arrived to survey the undeveloped land. catalogue it all and all you've got's a story in which every feature, no matter how seemingly insignificant, will like play an ineliminable role in the story of the fall. and, anyway, you could just keep rolling that film back forever. where does the story even start?
how, then, do we pick out the salient facts? the one's rightly named 'cause'? there are lots of philosophers who talk about causation in lots of different ways (probabilistic causation, backward causation, causal processes, the metaphysics of causation-- and that's not even touching on aristotle, who divides the universe of causes into four distinct sorts: material, formal, efficient, and ultimate), but what i'll be discussing here are counterfactual theories of causation, which ground what is known in legal and philosophical contexts alike as 'but-for' causation. In it's broadest form this is just to say that 'A caused B' is to be understood as the claim 'if A had not occurred, then B would not have occurred.'
but this doesn't get us too much further along than our perfect catalogue of events. a significant subset of the list of features will likely amount to causes by this definition. what we need to find are those subset of causes (in the broadest sense of that that term) which are not just necessary, but sufficient ('determinants', lewis calls them). so long as this feature (or set of features) is present, this enough to ensure that the bridge will fall. the relevant formula is now more demanding-- for A to be a cause in this stricter sense it must be true that so long as A has occurred, then B will occur.
oh, crum. leah is here early. and i haven't even gotten to overdetermination yet! i haven't even turned my little philosophy lesson into anything meaningful! i guess it's the nature of these exercises. i will continue to work on this, but i'm going to post it now anyway, in the spirit of the task i set myself.