TGGP—You seem to have missed the conditional nature of my claim. I’m not forcing philosophy on anyone; just saying if you’re going to do it at all, best do it well.
Nick—I never suggested there was an “abiding personal essence”. (Contemporary philosophers like Derek Parfit and David Velleman have done a stellar job in revealing the conceptual confusions underlying such an idea.) In any case, it’s hardly relevant. The issue here is individuation (how to count the distinct things in the world), not personal identity and persistence through time.
James—if you’re asking what difference identity makes, that’s a good question. To answer literally, if “two” things are really identical, i.e. really one, then there is no possible world (however distant or “unrealistic”) where they come apart—where there is one without the other. That’s arguably the criterion for what it is to be one rather than two. Now you may ask why we should care about this difference. Here’s an answer: we care about the fundamental constituents of reality, or “what it takes” to create a world like ours. Imagine a god were to create all the physical stuff of our universe. Does that suffice, or does he have more work to do before he can rest? My earlier arguments suggest that there is more work to do here. He also needs to add some extra, ‘bridging’ psycho-physical laws of nature, to ensure that brainy matter gives rise to conscious minds. If they were truly one and the same thing, this extra step would not be required. (Cf. airplanes.) That’s an interesting result, no?
TGGP—You seem to have missed the conditional nature of my claim. I’m not forcing philosophy on anyone; just saying if you’re going to do it at all, best do it well.
Nick—I never suggested there was an “abiding personal essence”. (Contemporary philosophers like Derek Parfit and David Velleman have done a stellar job in revealing the conceptual confusions underlying such an idea.) In any case, it’s hardly relevant. The issue here is individuation (how to count the distinct things in the world), not personal identity and persistence through time.
James—if you’re asking what difference identity makes, that’s a good question. To answer literally, if “two” things are really identical, i.e. really one, then there is no possible world (however distant or “unrealistic”) where they come apart—where there is one without the other. That’s arguably the criterion for what it is to be one rather than two. Now you may ask why we should care about this difference. Here’s an answer: we care about the fundamental constituents of reality, or “what it takes” to create a world like ours. Imagine a god were to create all the physical stuff of our universe. Does that suffice, or does he have more work to do before he can rest? My earlier arguments suggest that there is more work to do here. He also needs to add some extra, ‘bridging’ psycho-physical laws of nature, to ensure that brainy matter gives rise to conscious minds. If they were truly one and the same thing, this extra step would not be required. (Cf. airplanes.) That’s an interesting result, no?