Every day, he suggests, kiss your partner for six seconds. That’s one six-second kiss, mind you, not six one-second kisses. Six seconds is, if you think about it, a potentially awkwardly long kiss. But there’s a reason for it: Six seconds is too long to kiss someone you resent or dislike, and it’s far too long to kiss someone with whom you feel unsafe. Kissing for six seconds requires that you stop and deliberately notice that you like this person, that you trust them, and that you feel affection for them. By noticing those things, the kiss tells your body that you are safe with your tribe.