Donald Trump gave us a textbook example of one type of an "Insincere Smile" while speaking in Sarasota on Saturday. In fact, for the businessman-turned-politician, this particular nonverbal is a very common one.
At 0:36 (in above video) Trump begins, "You see how diplomatic I've become? [pause] Right?"
The vast majority of the time, a unilateral smile is insincere - and this example is not one of the exceptions (Do you know how to differentiate these?).
Note how the right corner (Trump's right) of his mouth is down-turned, while his left side is vectored upward. This is a classic duplicitous (false) smile (yet not all one-sided smiles signify the same motives). This particular expression signals a disparity from what is being spoken vs. that which is thought-felt. Anytime the body language is saying one thing - and the verbal language is saying another - it's the nonverbal messages which are telling the truth.
A close-up of the above image of a Unilateral and Duplicitous, False Smile captured during 0:39
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