What the expression is intended to mean, I think, is that there is a better and a worse element in the character of each individual, and that when the naturally better element controls the worse then the man is said to be "master of himself", as a term of praise. But when - as a result of bad upbringing or bad company one s better element is overpowered by the numerical superiority of one s worse impulses, then one is criticized for not being master of oneself and for lack of self control.

What a poor appearance the tales of poets make when stripped of the colours which music puts upon them, and recited in simple prose.

The science [geometry] is pursued for the sake of the knowledge of what eternally exists, and not of what comes for a moment into existence, and then perishes.

Attention to health is life greatest hindrance.

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

When the tyrant has disposed of foreign enemies by conquest...and there is nothing to fear from them, then he is always stirring up some war

The soul of him who has education is whole and perfect and escapes the worst disease, but, if a man's education be neglected, he walks lamely through life and returns good for nothing to the world below.