Violent zeal for truth has a hundred to one odds to be either petulancy, ambition, or pride.

Heat in an argument rarely comes from the subject. When somebody is fierce about being right, the force is usually supplied by something personal: irritation, a wish to be seen as the one who knows, or a reputation that has become attached to the position. Genuine concern with what is true tends to be calmer, because it is prepared to be wrong. The intensity is the tell.

Next time you feel yourself getting heated about a point of fact, pause and ask what you would lose by being mistaken. Answer that first, then return to the actual question with less at stake.