Probably Approximately Correct: Nature's Algorithms for Learning and Prospering in a Complex World
Leslie Valiant
Basic Books, 2013 ($27.99)

Valiant, a computer science professor at Harvard University, takes as his point of departure Alan Turing's 1936 paper that laid the groundwork for modern computers. Turing was the first to suggest that computation was subject to finite rules and therefore capable of being carried out by machines. Valiant argues that all living things have been capable of computation since the beginning of time, using “ecorithms” to predict the future and adapt to it. His book is an engaging meditation on complexity and on how living things often unwittingly use math to navigate it.