Wei Dai wrote:

>Suppose someone offered you $1000, but if you accepted Earth >would be destroyed and everyone on it killed as soon as you die. Would you >take that offer? Even if you did I'm sure most people wouldn't. This is because I include in the first person its possible compassion feeling for what are possible others. (This is similar to what Brent Meeker said in its last post). Compassion, although it bears on others, is a feeling, isn't it? >I admit the decision theory approach I gave in the last post has problems, >some of which you've pointed out. But what's the alternative? I've been >thinking about this issue for several years, starting with the >expected-first-person-experiences approach (if you read the earlier >archives you'll see many posts from me on this). I did. (and it is why I try to understand your evolution). The very beginning of this discussion-list by you and Hal Finney has been very attractive to me at the start. I still don't understand your shift. >GTM means general Turing machine. It's defined in Jürgen >Schmidhuber's paper at http://www.idsia.ch/~juergen/toesv2/. Please read >it if you haven't already. I red it. I prefer its first paper, although its philosophical conclusions contradict what I found interesting in it. We discussed that. >Wait, even in the infinite the ratios will not be the same in general. Why >do you think they will be? Not so easy question indeed. But here the methodology I use forces me to define the measure by the AUDA logic Z1*. The "infinite ratios" will be the same thanks (hopefully) to the non trivial constraints given by computational self-reference. Remember that our first person expectations rely on *all* our consistent (self)-extensions. >If you read Schmidhuber's paper, you'll see that he offers several >measures for consideration. He believes that the Speed Prior is the >correct objective measure, This cannot be. The UDA shows our first person experiences cannot be aware of delays taken by any universal (classical or quantum, but immaterial) machine accessing our current states. Classical real time is definitely an emerging phenomena from UD* (all execution of UD). UDA predict that "we" are (perhaps) quick to be computed but our neighborhoods must be necessary much slow to be computed. (In that sense it predicts the computing power superiority of our neighborhood). You can interpret my work as saying that IF we are made of bits then we are necessarily embedded in a qubit "made" reality. I have made some recent progress in that direction. Normally Z1* should be equivalent to some sort of generic quantum computer. The incredible progress in that field could lead more quickly than I expected to a refutation or confirmation of comp. >Suppose you want to crack a bank's encryption key, which is worth $4 >million to you, and there are two ways to do it. You can spend $2 million >to build a quantum computer to crack the key, or you can spend $3 million >to build a classical computer to do this. Now if you believe the Speed >Prior is the correct measure, then you'll think that the quantum computer >will very likely fail, and therefore you should go with the classical >computer instead.But if you believe the Universal Prior is the correct >measure, then you'll think that both computers will work and you'll go >with the quantum computer because it's cheaper. OK. >However, there's another way to think about this situation that doesn't >involve an objective measure. The fast-to-compute and the slow-to-compute >universes both exist. You are taking the expression "universe" too literaly. The "slow-to- compute "multiverse" is equivalent to the sheaf of locally quick to compute "single computations", but we belong to the mutiverse: we belong to all universes. Objective measure are useful for taking into account the "proportion" of histories and this is what makes decision worthly senseful. >(The fast-to-compute universes are the ones where >quantum computers fail.) So when you adopt the Speed Prior you're really >saying "I know the slow-to-compute universes exist (and my actions affect >what happens in them), but I just don't care very much about those >universe." But (sorry for repetition) the UDA forces us to take those slow universe/computation into account. That's exactly the point of question 7 in the conversation with Joel Dobrzelewski. (links at http://www.escribe.com/science/theory/m3044.html, step 7 is at http://www.escribe.com/science/theory/m2992.html). You must care about those slow universe because their slowness just comes from the fact that their multiply you in important proportion. It is the very base of my proof that comp entails the quantum, and why if we are bit-describable then those bit are qubit made. >To me the attraction of think about it the second way is that it allows us >to just say that all universes exist. We don't have to say that >objectively one universe has a higher measure than another. What does that >mean anyway? If all universes exist, how is it that some universes have >more of an existence than others? We don't have to answer those questions. All "relative universe/computation" exists and are on the same ontological footing, but we must bet on those which are more likely to be apparent for ourself, which are the one which provide relatively more numerous consistent extensions with respect to our current state. That's what can make our decisions purposefull, I think. In Schmidhuber term we need a "high multiplication" prior, which makes our neighborhood consistent expectation very slow to compute. Bruno