I just finished chapter 11 where Adam defends the various many-worlds views (string theory’s landscapes, inflation’s multiverse, and Everett’s Many-Worlds Interpretation, MWI). He admits MWI has a problem with the meaning of probability, but dismisses it as something to be solved in the future. I’m less optimistic, since the idea has been in vogue (in FoP anyway) for many years and yet the problem persists. For example, it can’t be simply that the branches split with a “frequentist interpretation of probability,” as Adam illustrates with the Schrodinger Cat in a 25% dead — 75% alive probability when there are only two possible outcomes. Another problem with a frequentist-splitting interpretation would be that many branches would not in fact obtain empirical evidence for the correct splitting probabilities (as seen from a global perspective “outside” all the branches), as Adrian Kent pointed out years ago. So, how do we know we’re in a branch where our experiments actually reflect the correct probabilities? Finally, Adam defends these many-worlds views against accusations that they’re unscientific because they’re unverifiable. He properly points out that all scientific theories are unverifiable in the sense of Popper, e.g., deviations in Uranus’s predicted orbit led to the discovery of Neptune, not the overthrow of Newtonian gravity. Later, deviations in the orbit of Mercury did lead to Newtonian gravity being “falsified,” i.e., replaced by a more accurate theory (GR). Here I think Adam’s defense is strained at best. There is a huge difference b/w Newtonian gravity not being falsified by a single apparently discordant measurement (Uranus’s orbit) and the fact that EVERY POSSIBLE measurement outcome is compatible with a theory. To claim the former case is equivalent to the latter is an egregious misrepresentation of the objection of unfalsifiability. To paraphrase one opponent of such views, “Does a theory that predicts everything explain anything?” On to chapter 12!