Nobody asked for the favor, yet the moment you take it, a little debt clicks on inside you.

The reciprocity norm is a built-in social rule: when someone gives us something, we feel pressure to give back. The pull works even for favors we never asked for and even toward people we do not particularly like. Taking without returning feels like an open debt, so we repay to make the uneasy feeling go away.

An unsolicited favor quietly tilts you toward saying yes to whatever the giver asks next.

Learn the idea and practice English at the same time.