Thinking, Fast and Slow, by Daniel Kahneman. Should be read by all who wonder how our minds work - and how much happens "behind the scenes", "under the covers". Darwin's Dangerous Idea, by Daniel Dennett. Should be read by all curious to know the full implications of mechanistic evolution (hint: think about what came before life). The Mating Mind, by Geoffrey Miller. Must-read for anyone in marketing, or anyone wondering why the other guy got laid and you didn't. Guns, Germs, and Steel: The Fates of Human Societies, by Jared Diamond. Why are we rich and they poor? Why so few domesticated African animals? Why one big China and a many-state Europe? The Laughter of Triumph: William Hone and the Fight for the Free Press, by Ben Wilson. Great read about an early 19th C. struggle against unjust laws used to gag journalism. Relevant in today's age of bloggers, etc.
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