When it comes to the "Thumbs Up" body language display, it's important to see what may not-so-obvious. First - never forget the accompanying facial expression - for it's subconsciously driven, whereas the decision to display an upward thumb is a conscious one. It's always the subconscious component which tells the true emotions. Donald Trump's facial expression shown above is one of blended contempt, disgust and disbelief.
Yet there are further details for his thumb to reveal. Like many politicians (and of course people from all walks of life), when Mr. Trump uses the "Thumbs Up" display - his Thumb is rarely fully committed. Notice that the base of his thumb (proximal phalanges [or the singular, phalanx]) remains touching or very close to the rest of his hand - with only the distal end of his thumb extending away.
Ronald Reagan's thumb in this image from 1980 - his whole thumb is extended away from his hand.
Reagan's smile is also very sincere - thus his face and his hand are nonverbally congruent (vs. Trump's disparate body language).
Even when Mr. Trump's thumbs extend in this gesture a bit further - they rarely lengthened much more than what is seen here (on his right).
This website serves as an objective reference source for the science and art of Body Language/Nonverbal Communication. In an effort to be both practical and academic, many examples from/of varied cultures, politicians, professional athletes, legal cases, public figures, etc., are cited in order to teach and illustrate both the interpretation of others’ body language as well as the projection of one’s own nonverbal skills in many different contexts – not to advance any political, religious or other agenda.
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