The philosopher Ludwig Wittgenstein once remarked that if you ask a man how much is two plus two and he tells you five, that is a mistake. But if you ask a man how much is two plus two and he tells you ninety-seven, that is no longer a mistake. The man you are talking to is operating with a wholly different logic from your own.

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I'm from Minnesota. I'm optimistic. I mean, that's just who I am.

If you don't visit a bad neighborhood, it might visit you.

No matter what your profession – doctor, lawyer, architect, accountant – if you are an American, you better be good at the touchy-feely service stuff, because anything that can be digitized can be outsourced to either the smartest or the cheapest producer.

So what am I? I guess I would call myself a sober optimist...If you are not sober about the scale of the challenge, then you are not paying attention. But if you are not an optimist, you have no chance of generating the kind of mass movement needed to achieve the needed scale.

Criticizing Israel is not anti-Semitic, and saying so is vile. But singling out Israel for opprobrium and international sanction - out of all proportion to any other party in the Middle East - is anti-Semitic, and not saying so is dishonest.