No one can conceive the variety of feelings which bore me onwards, like a hurricane, in the first enthusiasm of success. Life and death appeared to me ideal bounds, which I should first break through, and pour a torrent of light into our dark world. A new species would bless me as its creator and source: any happy and excellent natures would owe their being to me. No father could claim the gratitude of his child so completely as I should deserve theirs.'
Mary Shelley, Frankenstein, or the Modern Prometheus1
The astonishing new developments in biology and genetics which have taken place over the last thirty years or so have made possible a whole new branch of technology which permits us to intervene in the processes of life itself and, to some extent, to shape and reshape human nature to our own design. The revolution in industrial technology in the nineteenth century was built upon the scientific revolution of the seventeenth and eighteenth centuries, and in much the same way the revolution in biological and genetic technology derives from recent scientific discoveries about the genetic mechanisms of living beings. So, from an understanding of the 'genetic code' which controls the development of different kinds of living organisms, including humans, ways have been found to manipulate the genetic mechanisms to create, in the laboratory, new forms of life that do not exist in nature and also to modify the genetic