X-Message-Number: 27581 Date: Sun, 05 Feb 2006 19:12:22 -0500 From: Francois <> Subject: Definitions of identity and computer chips Discussions of the nature of Identity have resumed for a while and I have had some new thoughts on the subject. I think the problem we are facing here is that we are arguing about two different things which we are confusing with each other. Therefore, one side's arguments are seen as invalid by the other side, and vice versa. But the arguments are valid when applied to the notions they aim to prove. I think Robert's mathematical definition of identity is probably perfectly valid, although I do not have the mathematical training to fully understand it. For the sake of argument, I will simply accept it as such. What, however, does it actualy prove? Well, it proves something I would call Objective Identity. It proves that indeed, objects A and B cannot be the same, however perfectly we make B a copy of A. At the very least, we still have two distinct objects we call A and B, and in no circumstances can A become B or B become A. That's Objective Identity. There is however a second kind of identity which I would call Subjective Identity. It is a property of sentient entities. Humans, and possibly many animals, fall into that category. Subjective Identity is the internal perception of being a certain individual and not another. Memories, feelings, desires, personality traits, the general shape, sounds , smells and other attributes of one's body all contribute to the creation of that sense of self. This is really what we want to preserve when we are talking about prolonging life. Lets revisit a philosophical problem I believe was submitted on cryonet some time ago. Individual A is on an out of control spaceship about to burn up in Earth's atmosphere, and there is nothing he can do about it. Aboard the ship is a device that can read an object's atomic structure and transmit that information to a recieving device on the ground. It uses the information to build a perfect replica of the object out of its own reserves of atoms. In desperation, individual A enters the transmiting device which dutifully performs its intended function. On the ground, the receiving device builds a perfect replica of individual A, lets call it individual B. The process is completed before the spaceship is destroyed. Individual B walks out of the device totally unharmed, while individual A is killed when the spaceship breaks up in the atmosphere and is totally incinerated. Did individual A escape the doomed ship or not? Well, according to Robert's definition of idendity, of course not. Individual A was killed in the crash, and what walks out of the replicating machine is individual B, a clearly different individual. From the point of view of Objective Identity, this is trivially obvious and cannot be contested. However, from the point of view of Subjective Identity, Individual A did escape. Lets say that individual A called himself Sam. Individual B will therefore also call himself Sam. He has Sam's memories, feelings, desires and personality traits. His body is atomically identical to Sam's body. If the receiving device was at an appropriate location, he could have walked out, looked up at the sky and witnessed the fiery destruction of the spaceship, a spaceship he would have remembered having been on only moments ago. Individual A dies, individual B comes into existence, but the person that calls himself Sam lives on. Sam's opinion is the only one that matters, and a person calling itself Sam clearly exists in Individual B just like it existed in individual A. Sam did escape the spaceship. This can be illustrated even more convincingly by one of Robert's own examples. He evoked the possibility of taking an old 8086 chip and offering it to be converted into a modern Pentium IV, only to dismantle it and building a new Pentium IV out of different atoms. The 8086 itself, of course, would not have survived the procedure, but we can approach the problem from a very different angle. Suppose we have a sentient program running on that old 8086. It is not a human brain simulation or any kind of simulation, it is an actual pure software program, an assemblage of heuristic algorithms, routines and subroutines, something that behaves very much like the Doctor program on Star Trek Voyager. It has routines that receive and interprets inputs from digital cameras which allows it to see, routines that understand and interpret speach, which alows it to understand people talking to it, routines that can create meaningful sentenses in response, which allows it to hold intelligent conversations with people, etc,. The global network of interractions between all these routines is what ultimately gives sentience to the program. We now tell that program that we will transfer it to another machine, one that uses a Pentium IV. The program is turned off, saved on the 8086 machine's hard drive and uploaded to the hard drive of the Pentium's machine. The old 8086 machine is then unplugged and thrown in the trash. The sentient program is now dead. It is then loaded into the Pentium IV machine and started up again. The program has been brought back to life and as far as it's concerned, nothing much has happened, except that it now finds itself running on a much better machine then before. The Objective Identity of the program is no longer the same, but it's Subjective Identity has not changed. Francois The Devil fears those who learn more than those who pray Rate This Message: http://www.cryonet.org/cgi-bin/rate.cgi?msg=27581