Delete comment from: Edward Feser
Anonymous,
On the materialism presupposed for your argument, I'm not sure it's possible for humans to have perfect doubles.
It could be said that at the moment I got different stimuli picked up by my sensory organs, my "two brains" would diverge in structure (due to having to process different input) and there would instantly (or at least VERY QUICKLY) be two completely different people, or sense of "I".
Suppose brain divergence does occur due to different stimuli. Since persons x and y are numerically non-identical to each other, it's impossible for them to at any point share identical spatiotemporal histories.
If x and y having different locations from each other is enough to cause these brain divergences, this means person x's brain could never at any moment be identical to person y's brain. So, if x and y having different locations from each other is enough to cause brain divergences (and, at least, I see no reason why it wouldn't), persons x and y are at every point in their histories qualitatively (as well as numerically) non-identical.
Mar 2, 2015, 3:25:36 PM
Posted to Descartes’ “indivisibility” argument