Fairly interesting, but a slow read to follow all the logic. I didn't realize when I picked it up that it was so much of a deep philosophy book, and clearly written by the author who disagrees with the established views on this subject, though I am in no place to assess the difference of opinions. ( )

An interesting read if you have any interest at all in philosophy of time and how it relates to Einstein's theory of relativity. Yourgrau highlights an intriguing and under-appreciated relationship between the logician Kurt Gödel and Einstein, which led to a surprise finding by the former: if we accept relativity, then we cannot treat our notion of time as a physically-real property of the universe. The whole idea sounds daunting, and the subject matter most certainly is if you dig into the guts, but Yourgrau wrote this book for the lay audience and did a wonderful job of it. ( )

A little long winded at times. The last chapter is an absolute throwdown against some perceived disrespect of Gödel the philospher. "... worse than misguided..." -- those are fightin' words! ( )

I read this book and "Incompleteness" by Rebecca Goldstein at the same time. They are both quite good books and, as written by academic philosophers, generally mitigate my general negative opinion of academic philosophy. If you are interested in Goedel's ideas about "time travel" then this is your book. (It's actually not a "Star Trek" type concept, as Yourgrau makes clear.) If you are more interested in the proof itself, read Goldstein, who goes into more detail. But really you should read both, because unlike some philosophers from Austria that I could name (ahem! cough, cough!), they actually take the time to try to explain things to you. I should say that it improves my opinion of academic philosophy, except for one problem -- both books make clear, this one even more than Goldstein's, that Goedel was rejected by most of academic philosophy, many of the members of which didn't even understand what Goedel was talking about. There is an explanation of "Goedel's proof" of the incompleteness of mathematics (actually two proofs, as it turns out) which is quite accessible. You also get a good idea of how Goedel's mind worked, sometimes for the better and sometimes for the worse, and why his ideas about time are philosophically important. If time travel is possible, even if it is in a world with different properties (a rotating non-expanding universe or whatever), then the whole concept of time as experienced subjectively needs to be re-evaluated. It is really astounding that this master logician, who should be the hero of all the "analytic" philosophers in the U. S. A. -- since he proved something really significant about logic and mathematics that rivals or exceeds Aristotle -- is hardly even regarded as a philosopher at all, a fact which reveals the shallowness of modern academic philosophy. ( )

Yourgrau's book does have some redeeming qualities: an intriguing theme and an impressive cast of characters, presented with a wealth of historical and personal detail. Unfortunately, however, the line between detail and minutiae can be a fine one, and the reader is occasionally subjected to a celebrity-magazine level of the latter, as when Yourgrau explains, "History, sadly, does not record which of the seven dwarfs was Gödel's favorite." He also gives Gödel's date of death as January 11, 1978, which is interesting, since other sources, the New York Times included, seem to consistently place it three days later, on the 14th of the month.

The style of the book veers from grandiosity to flippancy in the early chapters, although it settles down in the more philosophically-oriented sections. Awkward turns of phrase abound, and the text is sprinkled with such inanities as, "Time itself must have been smiling over the puzzle it had created." Most of the technical material is covered clearly enough, however, although a few more definitions might not have been amiss in a work intended for what Yourgrau calls "normal readers." ( )