A little snap judgment goes a long way toward making friends: Marc Salem, Ph.D., a behavioral psychologist says , all it takes is 20 seconds to decide whether or not a stranger is trustworthy.
1. Inconsistent behavior
If normally someone is very still, and suddenly they become very animated, or vice versa, that change-up is a red flag. The same goes if a person is speaking smoothly and rapidly, but suddenly their speech becomes more deliberate or clipped. Shifts from the norm are red flags for deceit.
2. A steady gaze
When people think or contemplate, it’s natural for them to break eye contact and look around. If a person’s gaze is too constant, they’re either not listening or consciously trying to earn your trust. Both are signs of insincerity.
3. Not enough mouth
Coughing, clearing the throat frequently, or any other gesture of covering the mouth can indicate that a person is trying to hide something. The same goes for a shoulders-down, hunched-body pose. That’s a sign of caution and indicates a person is not opening himself up completely.
4. A quick smile
A genuine smile changes a person’s whole face. Their eyes light up, and their cheeks and eyebrows rise along with the corners of their mouth. That smile also takes a few seconds to fade. A fake smile appears in an instant, and disappears just as quickly.
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