I find that I often have trouble understanding posts on this mailing list, given the wide range of intellectual ground that it covers. It seems that people sometimes assume a background in an academic field, and I'm not even sure what the field is, or how to get up to date or at least familiar with it. On the other hand, sometimes a poster is just a crank and isn't making any sense at all. It can be hard to tell the difference.
Perhaps it would help if list members each posts a short biography of themselves, and tell us their intellectual backgrounds. What fields are you familiar with, what relevant books/papers have you read, etc.? This way, if you don't understand someone's post, you can look up his JOINING post in the archive and figure out what background he is assuming. I got this idea from the SL4 mailing list; maybe it will work here as well. To begin with myself, I work as a cryptographic engineer, which means I design and implement computer security mechanisms, with a focus on the cryptographic parts. I have a BA in computer science, and have taken courses in linguistics, theory of computation, number theory, algebra, probability theory, and game theory. I think I first encountered the idea that all possible universes exist in the novel _Permutation City_ by Greg Egan, and then in Tegmark and Schmidhuber's papers. I started this mailing list after reading both of those papers. I've scanned through _An Introduction to Kolmogorov Complexity and Its Applications_, Ming Li and Paul Vitanyi, and read parts of it in enough detail to have found several previously unreported errors. It's about algorithmic information theory, and I personally think it is the single most important book for list members to read. Here are some other books that I've read outside of formal education that seem relevant. _The Selfish Gene_, Richard Dawkins. Theory of evolution. _Gödel, Escher, Bach - an Eternal Golden Braid_, Douglas Hofstadter. On self-reference. _Maxwell's Demon: Entropy, Information, Computation_. Entropy and the physics of computation. _Philosophy of Mathematics: Structure and Ontology_, Stewart Shapiro. I'm finding that I don't have enough knowledge about foundations of mathematics, foundations of decision theory, and quantum mechanics. I'm currently reading the following books to rectify the situation: _The Foundations of Causal Decision Theory_, James Joyce _A Modern Approach to Quantum Mechanics_, John S. Townsend _Foundations Without Foundationalism : A Case for Second-Order Logic_, Stewart Shapiro Ok, who wants to go next?