“What good is God?” is the title of this year’s Bannan Institute programme at Santa Clara University, the Jesuit school in California’s Silicon Valley. This month it invited me to ask: why does science need God? I proposed that the answer is found in a different question: why do we do science?What do we hope to achieve when we decide to be a scientist? What counts as success? Tenure, prizes, citations in the literature … are those the ultimate goal of science? And what motivates us personally to choose to do science, instead of going into banking or selling ties? Maybe it is the pleasure in finding patterns and solving problems; doing science is like being paid to solve jigsaw puzzles. But is that our ultimate goal? Would we give up tenure for the chance to