Christopher Hitchens was a great orator, polemic and knew his history nearly as well as he knew how to captivate an audience. One of my favorite quotes from him sums him up his career pretty well - when asked why he became a journalist he said, "Because I didn't want to have to rely on the media for my information."
He was (perhaps still is) the only journalist to have traveled to Iran, Iraq (before and after the war), and North Korea. He also traveled to Palestine, Israel, and moved back and forth between the opposing sides of Crete. I don't think there was ever alive a person as well versed, educated, and internationally experienced as the man.
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But I think my all time favorite is the neuroscientist Sam Harris. His musings on morality and free will have been absolutely mind opening to me and have truly informed how I perceive world as a moral landscape. If ever there was a jedi master of meta-ethics, surely it is this man.
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https://www.youtube.com/watch?v=DMFnSTPsbFg
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