Worth the time - physicsworld.com
"The subject of Dan Falk's In Search of Time is actually one step beyond these deeply perplexing mathematical questions. While we might think we understand time, unlike the "solidity" (and, dare I say it, the timelessness) of the above mathematical problems, there is absolutely nobody on Earth who knows what time is. Or, for that matter, if it even exists. Falk is frank about this right from the start, beginning with St Augustine's famous lament in his Confessions: "What, then, is time? If no-one asks of me, I know. But if I wish to explain to him who asks, I know not.""