On Philauthorphy

Will Durant says in The Story of Philosophy (p. 61):

We have always goodly stock in us of that which we condemn: as only similars can be profitably contrasted, so only similar people quarrel, and the bitterest wars are over the slightest variations of purpose or belief. . . . Aristotle is so ruthless with Plato because there is so much of Plato in him . . .

I agree. However, as a footnote, I am saying that a person in a bitter quarrel with a similar person is not necessarily blind to the fact that they are so alike, or that the quarrel should necessarily be less bitter since those involved have much in common. It is one thing if a person does not understand me, for then he is ignorant; but it is another thing if a person understands me completely but refutes me. Only in the latter is there a conscious denouncement of my way of life. For this reason, in a sense the latter is worse, and thus can the bitterness of the quarrel be justified.

However, it is possible that, especially in the realm of philosophy where the ultimate pursuit is knowledge, it is actually a superficial rather than a genuine bitterness. In this case the quarrellers are in fact very naturally revelling in the simple state of affairs that they can have so fierce a quarrel; because to be able to quarrel as such, both participants must understand fully the other's train of thought. And though they may disagree, the mutual understanding is nonetheless a validation of existence for each person, and a rare validation--for it is very seldom that a person is found who can understand to this extent.