Take it easy: that's Michio Kaku's motto. Given the extraordinary advances science has thrown up in time for the millennium, the only way you could possibly fit them into a single volume is by a correspondingly massive simplification. Subtitled "How science will revolutionise the 21st century and beyond" Visionsassumes that by and large scientists get to do whatever they like, that all technologies are consumer technologies and that consumers welcome anything and everything science throws at them. Kaku gets away with this frankly dodgy strategy by dint of sheer hard work. He has based his predictions on interviews with more than 150 renowned working scientists, he integrates these interviews with a huge body of original journalistic material and above all he roots that mass of information on an entirely reasonable model of what the purpose of science will be in the third millennium. Up until now, science has expended its efforts on decoding most of the fundamental natural processes--"the dance," as Kaku puts it, of elementary particles deep inside stars and the rhythms of DNA molecules coiling and uncoiling within our bodies". Science's task now, Kaku believes, is to cross- pollinate advances thrown up by the study of matter, biology and mind--modern science's three main theatres of endeavour. "We are now making the transition from amateur chess players to grand masters," he writes, "from observers to choreographers of nature." Then again, he also believes that "the Internet...will eventually become a "Magic Mirror" that appears in fairy tales, able to speak with the wisdom of the human race." Kaku, in short, deserves a good slapping--but he also deserves to be read. --Simon Ings