NPR's 'Math Guy' explains changing nature of mathematical proof

Keith Devlin is a consulting professor in Stanford's Mathematics Department and a fellow of the American Association for the Advancement of Science. Some biologists recognize his name because there's an extinct possum named after him, but most people know him as "the Math Guy" on National Public Radio's Weekend Edition, where he explains the math behind-among other things-why giving an extravagant gift of no lasting value, such as an expensive meal, will maximize the success of a budding romance.