Friendship is essentially a partnership.

The greatest of all pleasures is the pleasure of learning.

Today, see if you can stretch your heart and expand your love so that it touches not only those to whom you can give it easily, but also to those who need it so much.

It is clear, then, that the earth must be at the centre and immovable, not only for the reasons already given, but also because heavy bodies forcibly thrown quite straight upward return to the point from which they started, even if they are thrown to an infinite distance. From these considerations then it is clear that the earth does not move and does not lie elsewhere than at the centre.

That judges of important causes should hold office for life is a questionable thing, for the mind grows old as well as the body.

We are what we repeatedly do.

There are some jobs in which it is impossible for a man to be virtuous.