"They all pose as though their real opinions had been discovered and attained through the self-evolving of a cold, pure, divinely indifferent dialectic (in contrast to all sorts of mystics, who, fairer and foolisher, talk of “inspiration”), whereas, in fact, a prejudiced proposition, idea, or “suggestion,” which is generally their heart’s desire abstracted and refined, is defended by them with arguments sought out after the event. They are all advocates who do not wish to be regarded as such, generally astute defenders, also, of their prejudices, which they dub “truths,”—and VERY far from having the conscience which bravely admits this to itself, very far from having the good taste of the courage which goes so far as to let this be understood, perhaps to warn friend or foe, or in cheerful confidence and self-ridicule."
— Nietzsche, who apparently had to deal with People Who Argue On The Internet more than a hundred years early.