A TWO-DAY symposium at the United States Library of Congress, entitled “Preparing for Discovery”, to discuss the possible impact on society of finding life in space, was my destination this month. Discovering life outside Earth would be a major advance in understanding biology; finding intelligent life would colour how we understand being human. But it is a magnet for our hopes and fears. The field of astrobiology still has a hard time escaping the taint of “little green men”. Thus nearly all the speakers went out of their way to emphasise that they were “serious scientists”, viewing life and intelligence from a purely secular and, indeed, materialistic viewpoint. Constant reference was made to the “N=1” problem: how can you define life, muc