Jan Swammerdam, mystical materialist.
Jan Swammerdam (1637-1680) was a renowned microscopist, anatomist and experimenter who lived in the Dutch Republic, and is now largely forgotten. But he helped contribute to one of the most important breakthroughs in the history of science - understanding where life comes from. Not only did he show that "all animals come from an egg laid by a female of the same species", he was also part of a small group that made the amazing discovery that women have eggs. But Swammerdam was not a modern day life scientist transposed back to the time of Rembrandt and Vermeer. He was a product of his time, profoundly mystical and deeply religious - he even gave up science for a couple of years, in order to join a bizarre sect that believed that Adam and Eve were hermaphrodites. By looking at his life, work and opinions, we can see that the road to the full development of scientific, rational thinking was not straightforward, and involved people who simultaneously believed in completely contradictory things.
Matthew Cobb is an acclaimed science-communicator, scientist and writer who spent most of his adult life living in Paris, where he worked as a scientist and spent a great deal of time active in far-left politics. His day-job is studying the sense of smell in fruitfly maggots, and being in charge of Manchester University's Zoology degree. He also studies the history of science, and recently published a book ("Generation" in the US, "The Egg & Sperm Race" in the UK and Commonwealth). He also writes regularly on science and historical issues for the LA Times and the Times Literary Supplement.