David Brin, one of my favorite current sci-fi writers, offers these two quotes:

"Scratch the surface of most cynics and you find a frustrated idealist -- someone who made the mistake of converting his ideals into expectations."
- Peter Senge


"Any comfortable American who is cynical of progress -- or the competent decency of modern civilization -- hasn't pondered how life was for our ancestors. Any day that cossacks haven't burned your home should start out a happy one, overflowing with optimism."
- M.N. Plano

These two, and a lot more good thinking besides, can be found in his lengthy address to Libertarians called Essences, Orcs and Civilization:The Case for a Cheerful Libertarianism which I recommend to the thoughtful among us.

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