Why do we smile?

A smile can say a lot, but it's not all positive.


Asked by: Ceres Woolley Maisch, London

Smiling is a social signal which, usually, communicates to others our positive emotion and intent. When we feel good or we’re pleased to see someone, this emotion plays out in our facial expression. This sounds very jolly, but in some contexts smiles can also convey fear or submissiveness. Researchers who studied the facial expressions of martial arts fighters facing off before a clash found that those who smiled were more likely to go on to lose: the theory is that in this case their smile betrayed their fear or inferiority.

A related important distinction is between genuine, involuntary smiles, which are marked by greater creasing around the eyes, and deliberate or feigned smiles, which are deployed strategically to convey happiness, pleasure or deference, and lack the telltale eye wrinkling.

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