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Smile when the situation doesn’t call for it. Smile when you’re feeling angry, when you’re feeling miserable, when you’re feeling most crushed by the world—and see if it makes any difference.
Smile at strangers in the street. New York can be dangerous, so you must be careful. If you prefer, smile only at female strangers. (Men are beasts, and they must not be given the wrong idea.)
Nevertheless, smile as often as possible at people you don’t know. Smile at the bank teller who gives you your money, at the waitress who gives you your food, at the person sitting across from you on the IRT.
See if anyone smiles back at you.
Keep track of the number of smiles you are given each day.
Don’t be disappointed when people don’t smile back at you.
Consider each smile you receive a precious gift.
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Paul Auster, “Personal Instructions for Sophie Calle on How to Improve Life in New York City (Because she asked…),” collected in Gotham Handbook.