There have always been two ways to interpret the interrelationship between the physical world and our minds. The first one is to consider the physical world to be fundamental; from this perspective, the appearance of the mind is to be understood with the help of some neurological theory that maps physical states of the brain to states of the mind or observer moments. The second way starts with the mind, denying the fundamental role of the physical world. According to this assumption, the physical world is introduced with the help of a theory of physics mapping mental states to physical states that reproduce the mental state within themselves. Imprecisely speaking, the second way questions the reality status of the physical world.

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Both ways allow the elaboration of an ensemble theory. The first approach starts from the ensemble of all physical worlds (or formally with descriptions thereof). The second approach uses the ensemble of all observer moments (or descriptions thereof). When Rolf expressed the idea "UTM outputs a qualia, not a universe" (which is similar to the second approach), I wrote: "I have always been hopeful that both approaches will finally turn out to be equivalent." It's a very trivial fact though that the two approaches are not equivalent. Nonetheless it's interesting to note it. I argue that we have good reasons to discard the second approach. The fundamental role will be assigned to the physical worlds (hence the title of this message). The difference between the two approaches leads to different expections to the question "What will I experience next?". Consequently it can be measured empirically. We find this result by observing that different physical worlds may produce the same observer moment (e.g. if the physical worlds differ in a detail not perceivable by the observer). This assigns a higher probability to the observer moment when chosen randomly in order to answer the question (it's multiply counted because it appears more than once in the everyting ensemble). Opposed to this, every observer moment (in the RSSA within a given reference class) would have an equal probability to be selected if we used the second approach. I think that the quantum mechanical Born rule strongly supports the first approach: Observer moments are weighted according to a specific formula. They don't have equal probability! Example: Both quantum states, |A> = |0>/sqrt(2) + |1>/sqrt(2) and |B> = |0>/sqrt(3) + |1>/sqrt(1.5) lead to the same two possible observer moments when a measurement in the (|0>,|1>) basis is performed. According to the Born rule the probabilites for the two observer moments are equal for |A> and different for |B>. Starting from the second approach (observer moments are fundamental) this result cannot be understood. If we take this result seriously, Bostrom's self-sampling assumption "Each observer moment should reason as if it were randomly selected from the class of all observer moments in its reference class." should be modified: "Each observer moment should reason as if it were randomly selected from the class of all observer moments in its reference class, weighted with their frequencies in the Everything ensemble." In order to avoid misunderstandings, I want to add that I consider the Everything ensemble (in both approaches) as given. It's not the output of some UTM. Youness Ayaita --~--~---------~--~----~------------~-------~--~----~ You received this message because you are subscribed to the Google Groups "Everything List" group. To post to this group, send email to [EMAIL PROTECTED] To unsubscribe from this group, send email to [EMAIL PROTECTED] For more options, visit this group at http://groups.google.com/group/everything-list?hl=en -~----------~----~----~----~------~----~------~--~---