of facts they demand in their science, but by their world-view. Wherever the evidence seems to point, they refuse to go beyond physics to metaphysics. It would be difficult for anyone to be more up-front about this than Professor Richard Lewontin, geneticist, biologist and social commentator at Harvard University: ‘Our willingness to accept scientific claims that are against common sense is the key to an understanding of the real struggle between science and the supernatural. We take the side of