Contempt is the only asymmetrical expression in the muscular facial system: Disgust, fear, happiness, surprise and anger typically express themselves symmetrically. Contempt is marked by one lip corner pulled up and in a dismissive sneer.

Contempt is the only asymmetrical facial expression, so it's easy to spot once you're aware of its signs. One researcher has successfully tracked it in couples as a predictor of divorce. When someone is angry at you, you've still got traction with them, but when they display contempt, you've been dismissed.

Failure is a friend if we can see past the face of the foe that we project on it.

What looks like enjoyment is the sneer of contempt. That's not a smile.

A liar often smiles subtly while telling a lie; it's an unconscious expression of his delight in getting away with a whopper.

Con men look for human frailty to exploit. This is most often greed. Trump found a different vice: anger. The emotional are always the most susceptible to manipulation.