When I eat something hot (spicy), I might react by spitting out the morsel, but it's a voluntary reaction. Eating something overly sweet can also cause a voluntary reaction. But eating an especially sour candy can cause an involuntary reaction. It makes my eyes water, my saliva glands go into overdrive for a second, my face contorts, my whole body shivers for a second...it's not pleasant. Why is that? What part of our evolutionary growth would make us react that way?

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I was just sitting here contemplating the immortal words of Socrates who said, "I drank what?"

"Think of the rivers of blood spilled by all those generals and emperors so that, in glory and triumph, they could become the momentary masters of a fraction of a dot." --Carl Sagan "Pale Blue Dot"