We all have a tendency to think in terms of simple dichotomies, and often these dichotomies are strongly value-based and involve taking sides (good and bad, friend and foe, right and left ...).
The English writer Alan Bennett recalled that, as a child, he often saw inanimate objects as either good or bad, friendly or not friendly: one shoe brush (maybe the one for putting on the polish) was bad, the other (for polishing) good; one spoon was good, its fellow was bad, and so on.
Needless to say, these tendencies are stronger in some people than in others. They often manifest themselves in sporting or political contexts. Some people can watch a sporting contest or listen to a political debate without taking sides. Others - perhaps more naturally competitive - just can't be impartial.
A particularly amusing case relates to an old controversy between Isaac Newton and Gottfried Wilhelm Leibniz whose respective claims to have invented the calculus led to much dispute at the time. The mathematician Gregory Chaitin couldn't resist joining the fray - more than 300 years later! - and, what's more, highlighting the personal and moral qualities of the two long-dead antagonists:
"Newton was a great physicist, but he was definitely inferior to Leibniz both as a mathematician and as a philosopher. And Newton was a rotten human being ... Leibniz invented the calculus, published it ... and then was astonished to learn that Newton, who had never published a word on the subject, claimed that Leibniz had stolen it all from him. Leibniz could hardly take Newton seriously!
But it was Newton who won, not Leibniz.
Newton bragged that he had destroyed Leibniz and rejoiced in Leibniz's death ...
Morally, what a contrast! Leibniz was such an elevated soul that he found good in all philosophies ... It pains me to say [really?] that Newton enjoyed witnessing the executions of counterfeiters he pursued as Master of the Mint." [Meta math! The quest for omega (Vintage Books, 2005), p. 57]
Later, Chaitin pities Voltaire, who satirized Leibniz and praised Newton:
"Poor Voltaire - if he had read Newton's private papers, he would have realized that he had backed the wrong man!" [p. 59]