Those who watched the first Republican debate last night were not short-changed. Early on, Moderator and political anchor for Fox News, Bret Baier asked the ten candidates, "... Is there anyone onstage, and can I see hands, who is unwilling tonight to pledge your support to the eventual nominee of the Republican Party - and pledge to not run an independent campaign against that person? Again, we're looking for you to raise your hand now, raise your hand now if you won't make that pledge tonight."
Donald Trump then raises his right hand at 0:33 mark.
Trump then follows by raising both hands in a partial, palms-up display with a facial expression some would call "sheepish". We see in this angle a hint of a mouth smile.
Mr. Trump then makes this expression beginning at 0:39
This partially suppressed smile can be thought of as a form of what is known as "Duping Delight" (Ekman). Trump is taking pleasure in the act of threatening to run as an independent. He is feeling true joy from which cannot hide completely (although he is trying to camouflage it).
One crucial nonverbal take-home point illustrated here: When you believe you observe a microexpression, subtle-expression or any slight body language tell being displayed - and then you see a sudden movement or jerk of any part of the body or face - this is often a red flag that there are clandestine thoughts-emotions which the other person does not want to be revealed. Moreover, the way the human short-term memory works, sometimes when you see such a quick and unexpected movement - you may often recall an odd movement or out-of-place expression which had just occurred immediately prior (noticing it only in retrospect, in the short-term rewind-mode of your mind).
In addition, if it's not very obvious to you from Mr. Trump's verbal language during this debate (and of course other statements the candidate has made recently), his nonverbal language removes all doubt. Barring an implosion - which although predicted by many, has yet to happen - Mr. Trump will absolutely run as an independent candidate if he's not the Republican Party's nominee - and in many ways he's already doing so.
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