Who is John Galt? This week's Book Club podcast looks at the life, work and personality of Ayn Rand, probably the most influential writer you've never read. A favourite of our new Health Secretary, the author of Atlas Shrugged -- and the most strident advocate of the idea that "greed is good" -- continues to be revered and reviled four decades after her death. What was it that made her work speak so powerfully to so many? Does her philosophical system add up? How was she shaped -- first by the Russian Revolution and then by Hollywood? And where does prog rock come into it? I'm joined by Professor Lisa Duggan -- author of Mean Girl: Ayn Rand and the Culture of Greed, and Adam Roberts, the science fiction writer and professor of English at Royal Holloway, University of London.