X-Message-Number: 9336 Date: Mon, 23 Mar 1998 03:44:05 -0500 From: "Andrew S.Davidson" <> Subject: Dust to dust I think all of us here would agree that there is no elan vital but, like Mr Ettinger, I have trouble with the idea that our computational substrate is unimportant. My particular difficulty arises from a reading of the fine novel, Permutation City by Greg Egan. Read no further if you wish to avoid the spoilers which follow. The story concerns a community of uploaded humans. They exist on the future world's internet and their thoughts and simulated surroundings are implemented in a distributed way - buying computer cycles on processors when and where they are cheap. A weather forecasting crisis soaks up most of the world's computer power for a period and, during this interval, the poorer uploads are forced into suspended animation. This causes some alarm and a more secure substrate is sought. Our hero conducts experiments which demonstrate that the simulated mind survives any amount of time-slicing and real-world scrambling - all that matters is that the simulation is internally self-consistent. He proposes the "dust hypothesis" - that, once you have a sufficiently complex simulated universe, it can become independent of the original substrate - it will find itself in the dust of real-world space-time. The story concerns the fate of the folk who launch themselves into the dust in this way. So, my difficulty is that if the mind is independent of the substrate then what is to stop it latching onto other substrates across space and time? Perhaps this is happening all the time but our real world thread is just not aware of the spawned copies - something like the many-worlds interpretation of quantum mechanics. Perhaps time is purely subjective and so it is not possible for a mind to reorder itself across space-time in this way (Mr Ettinger's intuition that the nature of time is relevant seems sound to me). Andrew Rate This Message: http://www.cryonet.org/cgi-bin/rate.cgi?msg=9336