Learning to read body language is truly learning a ‘language’.
Take this board meeting; the chairman has his arms crossed and is virtually glaring.
What are you seeing?
The chairman feels under attack, feels weak, and that he has to defend his position. He will virtually die to defend his idea, and will probably make great errors. This is because, feeling attacked he must defend.
Now suppose you speak in a soft soothing voice, seeming to take his position.
“I think the Chairman is saying…” then somewhat readjust his views to be more palatable. Your soft voice and subservient stance will relax him and make him see you as an ally.
He is likely to agree with your adjustments.
You have ‘read’ him, you have recognised that his position has become, at the moment, his definition of self. To attack his position is like firing a gun in his face.
Since you ‘read’ him, you play the subservient, you speak low and sweet and seem to agree with him. He will see you as a ‘defender’ and align with you, and you can manipulate his views.
This is because everyone sees this argument as policy, arm’s length, not all that important, and he sees it as life and death.