What we know is not capable of being otherwise; of things capable of being otherwise we do not know, when they have passed outsideour observation, whether they exist or not. Therefore the object of knowledge is of necessity. Therefore it is eternal; for things that are of necessity in the unqualified sense are all eternal; and things that are eternal are ungenerated and imperishable.
While most of those who hold that the whole heaven is finite say that the earth lies at the center, the philosophers of Italy, the so-called Pythagoreans, assert the contrary. They say that in the middle there is fire, and that the earth is one of the stars, and by its circular motion round the center produces night and day.
To give away money is an easy matter and in any man's power. But to decide to whom to give it and how large and when, and for what purpose and how, is neither in every man's power nor an easy matter.
Men pay most attention to what is their own: they care less for what is common; or, at any rate, they care for it only to the extent to which each is individually concerned.
It [Justice] is complete virtue in the fullest sense, because it is the active exercise of complete virtue; and it is complete because its possessor can exercise it in relation to another person, and not only by himself.
Metaphysics is universal and is exclusively concerned with primary substance. ... And here we will have the science to study that which is, both in its essence and in the properties which it has.
Nature does nothing without a purpose. In children may be observed the traces and seeds of what will one day be settled psychological habits, though psychologically a child hardly differs for the time being from an animal.
For legislators make the citizens good by forming habits in them, and this is the wish of every legislator, and those who do not effect it miss their mark, and it is in this that a good constitution differs from a bad one.