Most helpful critical review
29 of 38 people found the following review helpful
Enjoyable book - but watch out for the error in Chapter 1.
on 5 July 2012
I found this book both interesting and enjoyable. The discussion on the implications of Einstein's theory was well presented. However I have to warn you about an error in Chapter 1 of the book which I will highlight briefly below.
To explain how knowledge affects probabilities the author gives the following example. Suppose you call a pet shop and tell them that you want to buy two male kittens. The owner tells you that he has just taken delivery of two kittens, a black and a tabby. If he tells you no more, then the chance that they are both males is 1 in 4 (assuming 50% of all kittens are male). If the owner tells you he has looked at the tabby and it's a male, then the odds of two males becomes 50%. All fine so far, but here comes the mistake. According to the author, if the pet shop owner tells you he has looked at one of the kittens and found it to be a male, but does not tell which one, then the odds of two males is 1 in 3 or 33%.
In fact, as soon as you know that at least one of the two kittens is male, the odds of two males becomes 50%, whether or not you know which one the pet shop owner checked. I would have thought such an error would have been spotted before the book was published and it did make me wonder whether I could rely on the more complicated explanations in the rest of the book. I also emailed the Professor pointing out what I believe is a mistake in the book, but so far, he has not replied.
Had it not been for the mistake I would have scored this book more highly. It is well written and I found it enjoyable and interesting.
Update - Since writing the orginal review I have now had email correspondence with Pof. Al-Khalili. He has agreed that the example in chapter 1 is incorrect and he intends to get in touch with his publishers to correct future editions of the book.