All noble things are as difficult as they are rare

All things excellent are as difficult as they are rare.

All excellent things are as difficult as they are rare.

The world would be happier if men had the same capacity to be silent that they have to speak.

Nothing in the universe is contingent, but all things are conditioned to exist and operate in a particular manner by the necessity of the divine nature.

I do not know how to teach philosophy without becoming a disturber of the peace.