If... the motion of the earth were circular, it would be violent and contrary to nature, and could not be eternal, since ... nothing violent is eternal .... It follows, therefore, that the earth is not moved with a circular motion.

A scrap of knowledge about sublime things is worth more than any amount about trivialities.

It is a sin directly against one's neighbour, since one man cannot over-abound in external riches, without another man lacking them.

For loving draws us more to things than knowing does, since good is found by going to the thing, whereas the true is found when the thing comes to us.

Pain itself can be pleasurable accidentally in so far as it is accompanied by wonder, as in stage-plays; or in so far as it recalls a beloved object to one's memory, and makes one feel one's love for the thing, whose absence gives us pain. Consequently, since love is pleasant, both pain and whatever else results from love, in so far as they remind us of our love, are pleasant.

Pray thee, spare, thyself at times: for it becomes a wise man sometimes to relax the high pressure of his attention to work.

Without doubt one is allowed to resist against the unjust aggressor to one's life, one's goods or one's physical integrity; sometimes, even 'til the aggressor's death... In fact, this act is aimed at preserving one's life or one's goods and to make the aggressor powerless. Thus, it is a good act, which is the right of the victim.