"The plan grows under the author's hand; new thoughts occur to him in the act of writing; he has not worked out the argument to the end before he begins."

"The like is not the friend of the like in as far as he is like; still the good may be the friend of the good in as far as he is good."

"Whenever anyone informs us that he has found a man who knows all the arts, and all things else that anybody knows, and every single thing with a higher degree of accuracy than any other man –whoever tells us this, I think that we can only imagine him to be a simple creature who is likely to have been deceived by some wizard or actor whom he met, and whom he thought all-knowing, because he himself was unable to analyze the nature of knowledge and ignorance and imitation."

"The whole life of the philosopher is a preparation for death."

"Beauty is certainly a soft, smooth, slippery thing, and therefore of a nature which easily slips in and permeates our souls."

"If one has made a mistake, and fails to correct it, one has made a greater mistake."

"I used to imagine that no human can make men good; but I know better now."

"'Excellence' is not a gift, but a skill that takes practice. We do not act 'rightly' because we are 'excellent', in fact we achieve 'excellence' by acting 'rightly'."

"They cross-examine a man’s words, when he thinks that he is saying something and is really saying nothing, and easily convict him of inconsistencies in his opinions; these they then collect by the dialectical process, and placing them side by side, show that they contradict one another about the same things, in relation to the same things, and in the same respect. He, seeing this, is angry with himself, and grows gentle towards others, and thus is entirely delivered from great prejudices and harsh notions, in a way which is most amusing to the hearer, and produces the most lasting good effect on the person who is the subject of the operation."

"The whole life of the philosopher is a preparation for death."