I was reading Lucian’s Life of Demonax here and came across this remark, which seemed eminently applicable to much online posting:
He once saw two philosophers engaged in a very unedifying game of cross questions and crooked answers. ‘Gentlemen,’ said he, ‘here is one man milking a billy-goat, and another catching the proceeds in a sieve.’
In Lucian’s Remarks addressed to an illiterate book-fancier here, we find another comment appropriate to those who always have a quote from an ancient source at their hands.
There are two ways in which a man may derive benefit from the study of the ancients: he may learn to express himself, or he may improve his morals by their example and warning; when it is clear that he has not profited in either of these respects, what are his books but a habitation for mice and vermin, and a source of castigation to negligent servants?
Most of Lucian’s works seem to be here.