"Now, William of Occam was a theologian, really, but he was closer to being a logician. He worked with logic, and he went to study theology at the University of Oxford. He had an uncertain history. We don't really know anything about his childhood other than he was given to the Franciscans, which gives you a clue he might have been an abandoned child, an orphaned child, an illegitimate child and just left at the monastery. So we don't really know anything much about his early life, but we do know he went to walk Oxford to study theology. And to give you a feeling for what the problem was really, theology was at that time called the Queen of Sciences. And that's because the way that people thought about the world is that theology, religion, metaphysics were all one. So yes, they had gods or angels in the sky pushing the heavenly bodies, and they had those spirits on earth causing plagues and stuff. And it was all one place. Everything was one place but with lots and lots of entities. And also part of the reason why it was called a science is that Thomas Aquinas a century earlier - another great theologian - had incorporated Aristotle's philosophy into Christian theology and came up with what he called theology as a science."Johnjoe McFadden is the author of Life is Simple, How Occam’s Razor Set Science Free and Shapes the Universe. He obtained his PhD at Imperial College London and went on to work on human genetic diseases and then infectious diseases, at the University of Surrey. Professor McFadden has specialised in examining the genetics of microbes such as the agents of tuberculosis and meningitis. His other books are Quantum Evolution: Life in the Multiverse, and Life on the Edge: The Coming of Age of Quantum Biology (co-authored with Jim Al-Khalili). He has published more than 100 articles in scientific journals on a wide range of subjects and lectures around the world. His present post is Associate Dean (International) and Professor of Molecular Genetics at the University of Surrey.www.surrey.ac.uk/people/johnjoe-mcfaddenhttps://johnjoemcfadden.co.ukwww.basicbooks.com/titles/johnjoe-mcfadden/life-is-simple/9781549112119www.creativeprocess.infowww.oneplanetpodcast.org