On Jun 20, 2005, at 10:44 AM, Hal Finney wrote:
Hal Finney wrote:
I think the practical differences are large, as you say, but I disagree that it points to a fundamental metaphysical difference. I think what appears to be a metaphysical difference is just the breakdown of our folk concept of "I". Imagine a primitive person who didn't understand the physics of fire, seeing two candles lit from a single one, then the first one extinguished - they may be tempted to conclude that the first flame has now become two flames. Well, this is no problem because flames never say things like "I would like to keep burning" or "I wonder what my next experience would be". We, however, do say these things. But does this bit of behavior (including the neural activity that causes it) make us different in a relevant way? And if so, how?
This breakdown of "I" is very interesting. Since there's lots of talk about torture here, let's take this extremely simple example: Smith is going to torture someone, one hour from now. You may try to take steps to prevent it. How much effort you are willing to put in depends, among other things, on the identity of the person Smith is going to torture. In particular, you will be very highly motivated if that person is you; or rather, the person you will be one hour from now. The reason for the high motivation is that you have strong desires for that person to continue their life unabated, and those desires hinge on the outcome of the torture. But my point is that your strong desires for your own survival are just a special case of desires for a given person's survival - in other words, you are already taking a third-person point of view to your (future) self. You know that if the person is killed during torture, they will not continue their life; if they survive it, their life will still be negatively impacted, and your desires for the person's future are thwarted.
Now, if you introduce copies to this scenario, it does not seem to me that anything changes fundamentally. Your choice on what kind of scenario to accept will still hinge on your desires for the future of any persons involved. The desires themselves may be very complicated, and in fact will depend on lots of hitherto unspecified details such as the legal status, ownership rights, etc., of copies. Of course one copy will say "I pushed the button and then I got tortured", and the other copy will say "I pushed the button and woke up on the beach" - which is exactly what we would expect these two people to say. And they're both right, insofar as they're giving an accurate report of their memories. What is the metaphysical issue here?