As statistical understanding has improved, analysts have been saying with increasing firmness that the trick is to be able to tell the signal from the noise, to tell what’s really happening from mere randomness. Yet in this highly original and challenging book, Blastland points out that if you discard noise you are discarding half the information — sometimes more than half — that you need for understanding things... The Hidden Half very definitely does not argue against acquiring knowledge, or using statistical measures. However, it is a reminder to show humility and to accept how sensitive to small changes are things we regard as fixed and stable parts of knowledge. It makes you look at all that you know in a different way. Sometimes it’s a bit disturbing. But so be it. Once you have read this book, you can’t unread it.