Natalie Angier in The New York Times:
As the festival of mandatory gratitude looms into view, allow me to offer a few suggestions on what, exactly, you should be thankful for. Be thankful that, on at least one occasion, your mother did not fend off your father with a pair of nunchucks, but instead allowed enough contact to facilitate your happy conception. Be thankful that when you go to buy a pale, poultrylike entity, the grocery clerk will accept your credit card in good faith and even return it with a heroic garble of your last name. Be grateful for the empathetic employee working the United Airlines ticket counter the day after Thanksgiving, who understands why you must leave town today, this very minute, lest someone pull out the family nunchucks.
Above all, be thankful for your brain’s supply of oxytocin, the small, celebrated peptide hormone that, by the looks of it, helps lubricate our every prosocial exchange, the thousands of acts of kindness, kind-of kindness and not-as-nakedly-venal-as-I-could-have-been kindness that make human society possible. Scientists have long known that the hormone plays essential physiological roles during birth and lactation, and animal studies have shown that oxytocin can influence behavior too, prompting voles to cuddle up with their mates, for example, or to clean and comfort their pups. Now a raft of new research in humans suggests that oxytocin underlies the twin emotional pillars of civilized life, our capacity to feel empathy and trust.
More here.