"Journey to the Edge of Reason, The Life of Kurt Gödel", by Stephen Budiansky. Even though it contains an introduction to his proof of the Incompleteness Theorems, you won't learn all too much about logic or mathematics, but it sure paints an interesting picture of the people involved at the start of the 20th century. "Silas Marner" by George Eliot. Has redefined humor for me. "Reinforcement Learning and Stochastic Optimization" by Warren B. Powell. I'm still not entirely sure what to think of his claims about unifying many scientific disciplines, but it sure is packed with a lot of information and theory.
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