Crick's co-discovery of the double-helix structure of DNA (for which he shared a Nobel Prize with James Watson and Maurice Wilkins) was a maddening pursuit beset with false ideas, sloppy models, inconclusive results and fiascos. This will not come as news to readers of Watson's 1968 bestseller The Double Helix. Part memoir, part scientific primer, Crick's gracefully written reminiscence is more concerned with elucidating the intuitive leaps, feats of intellectual courage and perceptual skills that underlie the act of scientific discovery. Writing about his own career with uncommon modesty, he describes his current research into human consciousness and neuroanatomy; brain science of the 1980s, he concludes, is much like molecular biology of the '30s: the major questions remain largely unanswered. One wishes Crick were less reticent about his personal life. His occasional technical forays here into natural selection, the deciphering of the genetic code and theories of perception illuminate how science works.