A good style must, first of all, be clear. It must not be mean or above the dignity of the subject. It must be appropriate.

My lectures are published and not published; they will be intelligible to those who heard them, and to none beside.

Youth should stay away from all evil, especially things that produce wickedness and ill-will.

One would have thought that it was even more necessary to limit population than property; and that the limit should be fixed by calculating the chances of mortality in the children, and of sterility in married persons. The neglect of this subject, which in existing states is so common, is a never-failing cause of poverty among the citizens; and poverty is the parent of revolution and crime.

Of mankind in general, the parts are greater than the whole.

The virtue as the art consecrates itself constantly to what's difficult to do, and the harder the task, the shinier the success.

While the faculty of sensation is dependent upon the body, mind is separable from it