Plato

And whenever any one 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 __hoever 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.

One man cannot practice many arts with success.

Knowledge unqualified is knowledge simply of something learned.

Then we shan__ regard anyone as a lover of knowledge or wisdom who is fussy about what he studies_

Knowledge is the food of the soul.

Those who don't know must learn from those who do.

Either we shall find what it is we are seeking or at least we shall free ourselves from the persuasion that we know what we do not know.

Life must be lived as play.

Poets utter great and wise things which they do not themselves understand.

Cunning... is but the low mimic of wisdom.

There are three classes of men; lovers of wisdom, lovers of honor, and lovers of gain.

The most important part of education is proper training in the nursery.

If a man neglects education, he walks lame to the end of his life.

The direction in which education starts a man will determine his future in life.

The punishment which the wise suffer who refuse to take part in the government, is to live under the government of worse men.

Democracy passes into despotism.

One of the penalties for refusing to participate in politics is that you end up being governed by your inferiors.

Bodily exercise, when compulsory, does no harm to the body; but knowledge which is acquired under compulsion obtains no hold on the mind.