The world could be changed forever by new biotechnologies- cloning, 'genomics' and, above all, by genetic engineering. 'Designer crops' -GMOs -are already with us. The 'designer baby' is now being planned. We need to understand the issues involved and to find acceptable and robust ways to control our own ingenuity. But how can we do so when the ideas seem so complex and various that even the experts appear confused?In the 1950s and '60s, growing peas in his monastery garden in Brno in Moravia, Augustinian friar Gregor Mendel worked out the basic laws of heredity. Once we understand what Mendel did and why - and why nobody did it sooner - all subsequent advances fall naturally into place and a brilliant light is thrown on to the future of humanity. The story of genetics and its underlying principles are utterly compelling - and beguilingly simple to grasp.