The philosophers, Chrysippus and Epicurus, were in this of two quite contrary humours: the first not only in his books mixed passages and sayings of other authors, but entire pieces, and, in one, the whole Medea of Euripides; which gave Apollodorus occasion to say, that should a man pick out of his writings all that was none of his, he would leave him nothing but blank paper: whereas the latter, quite on the contrary, in three hundred volumes that he left behind him, has not so much as one quotation.--[Diogenes Laertius, Lives of Chyysippus, vii. 181, and Epicurus, x. 26.]