Book excerpt: Foreword / Gilles Dowek -- On a transformative journey -- Bayes theorem -- Logically speaking... -- Let's generalize! -- All hail prejudices -- The Bayesian prophets -- Solomonoff's demon -- Can you keep a secret? -- Game, set and math -- Will Darwin select Bayes? -- Exponentially counter-intuitive -- Ockham cuts to the chase -- Facts are misleading -- Quick and not too dirty -- Wish me luck -- Down memory lane -- Let's sleep on it -- The unreasonable effectiveness of abstraction -- The Bayesian brain -- It's all fictions -- Exploring the origins of beliefs -- Beyond Bayesianism.