The human brain possesses stunning talents; we still have no idea how it does most of what it does. You might think that an organ of such power would represent the absolute zenith in biological design - Mother Nature's magnum opus. But according to my next guest, the opposite is true - the brain is more like a clumsy, two-bit contraption held together by duct tape and chewing gum. Gary Marcus is professor of psychology at New York University, and he's written a new book about what he sees as the brain's oddly jury-rigged design. It's called Kluge: The Haphazard Construction of the Human Mind.