Hi, > And exactly how "just is" any more useful or satisfying than "just > happens"? > I guess `just is' is a more appropriate term when we are considering > all 4 dimensions the same, but, like Kathy says, it means about the same > thing.
0) As I explained, it leads to different (philosophical) insights and standpoints. In the 4D picture nothing "happens", so I don't see any problem or paradox if time-slices are causally disconnected; there is no problem of what "happens" means, or paradox that U(t+eps) is not completely determined by U(t). Why should it? All of Rich's philosophical concerns disappear. I know it's hard to change fundamental views like that things "happen" and "time flows", but science did that before (e.g. with absolute time). 1) You didn't comment on Martin-Moef's solution, which can be regarded as a successful completion of van Mises-Wald-Church's attempt to define probability. M.L.-randomness is closely related to Kolmogorov complexity, both solve the problem what randomness means. So problem solved. But I guess you have a different opinion on that. 2) What about Cournot's interpretation of probability? The mathematical statement "An event that happens with probability 1" means that "the event happens for sure in our Universe". So problem solved. But I guess you have a different opinion on that too (One problem is that in practice you have to replace "w.p.1." by w.high.p., and you have to choose "high"?) > I think it's unscientific to be ABSOLUTELY SURE that every process > CAN be perfectly predicted/explained. 4) I didn't say that (In the real world you cannot be sure about anything). But my argument implied that a scientist must *believe* that every process *can* be perfectly predicted/explained i.e. is deterministic. > A scientist has an open mind > to the possibility that his/her pet theory may be wrong. And sure I neither said this. But a scientist's mind should not be so open as to believe that something can principally not be explained (and believing in true randomness comes dangerously close to it) -- That's the domain of religion. > A dyed in the wool subjective Bayesian who never assigns probability > zero to any physically possible event but who truly believes his/her > subjective probability assessments will never be convinced by any > amount of evidence that her model is wrong. No matter how > disconfirming the observations, she will simply think she has seen an > incredibly unusual sequence. 5) I'm not sure what this paragraph is meant to show. A Bayesian makes decisions on a mixture of all models, so the ones with small likelihood do not harm (or uses approximate MAP). So despite that (1) and (2) solve the problem of what probability means, one should not believe in true randomness according to (4). That's my current sate of mind. [ If the moderator feels that the discussion is going to get boring for the majority of readers he should feel free to block these posts, or we should take it offline by ourselves ] Marcus _______________________________________________ uai mailing list uai@ENGR.ORST.EDU https://secure.engr.oregonstate.edu/mailman/listinfo/uai
