Jesse Mazer writes:

Jesse Mazer writes (after quoting Stathis Papaioannou):

No doubt, common implementations of your mind will predominate over more bizarre ones at any given point in time. It is also possible to imagine some scenarios where you survive indefinitely with all of your friends, for example implemented in an Omega Point computer. But eternity is a very long time. If it is possible that the Omega Point computer can break down, then, as Murphy teaches, it certainly *will* break down - eventually.

Not if the probability of it breaking down decreases in a geometric way from century to century (or millennium to millennium, aeon to aeon, whatever) as more and more of the universe is incorporated into the giant distributed computing network (or as the increasing computing power allows for more and more sophisticated ways of anticipating and avoiding civilization-ending disasters). Like I said, if the probability of a catastrophic breakdown was 1/8 in one century, 1/16 in the next, 1/32 in the next, and so on, then the total probability of it breaking down at any point in the entire infinite history of the universe would be the sum of the infinite series 1/8+1/16+1/32+1/64+1/128+... , which is equal to 1/4. In such a branch there'd be a 3/4 chance that civilization would last forever.

It is possible that the probability of the computer breaking down decreases geometrically with time, as you say. However, as t->infinity, it is nevertheless increasingly likely to deviate from this ideal behaviour, and the measure of branches of the multiverse in which it does will approach zero. Remember, it is not the probability in any single branch which is important (in fact, in the MWI that would be a meaningless concept), but the measure across all branches.

It may be more likely to deviate from this ideal behavior, but it could deviate by approaching zero probability of breakdown faster than the ideal behavior predicts, instead of slower; when I said that the probability would be 1/8+1/16+1/32+..., I meant the *average* you get when you sum all possible future histories from that point, including both the histories where at some later time the probability was approaching zero even faster than predicted by the 1/8+1/16+... pattern along with the histories where at some later time it was approaching zero slower, or the probability of breakdown was even increasing. Since it's an average, that means that out of all future histories stemming from that time, in 3/4 of them civilization will never break down.

Jesse

There are two separate probabilities to consider here. One is the probability (3/4, as you show) that civilization will never break down if implemented on a computer with behaviour as specified above. The other is the probability that the actual hardware will work according to specification. I don't think you should conflate the two, effectively arguing that the hardware will work to specification because that is part of the specification!

There are two separate probabilities to consider here. One is the probability (3/4, as you show) that civilization will never break down if implemented on a computer with behaviour as specified above. The other is the probability that the actual hardware will work according to specification. I don't think you should conflate the two, effectively arguing that the hardware will work to specification because that is part of the specification!

`On the other hand (and perhaps this is what you meant), in the MWI, there will always be at least one branch where the Omega Point computer does work as advertised, and therefore this constitutes one possible means to achieve immortality. If it can somehow be shown that this is a much more likely scenario for sentience to survive indefinitely than the other possibilities, perhaps we can all look forward to this.`

`Returning to the original question, once you have settled into your new home, what is to stop all your friends disappearing, as before? The computer will try to prevent this from happening, and you could probably try the geometric series trick again (i.e. decreasing probability that your friends disappear), but in this case there will be nothing tying you to those ever-rarer branches where the hardware works as it is supposed to.`

--Stathis Papaioannou

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