Human existence is girt round with mystery: the narrow region of our experience is a small island in the midst of a boundless sea. To add to the mystery, the domain of our earthly existence is not only an island of infinite space, but also in infinite time. The past and the future are alike shrouded from us: we neither know the origin of anything which is, nor its final destination.

The art of music is good, for the reason, among others, that it produces pleasure; but what proof is it possible to give that pleasure is good? If, then, it is asserted that there is a comprehensive formula, including all things which are in themselves good, and that whatever else is good, is not so as an end, but as a mean, the formula may be accepted or rejected, but is not a subject of what is commonly understood by proof.

There is one plain rule of life. Try thyself unweariedly till thou findest the highest thing thou art capable of doing, faculties and outward circumstances being both duly considered, and then do it.

What is contrary to women's nature to do, they never will be made to do by simply giving their nature free play.

The ends of scientific classification are best answered, when the objects are formed into groups respecting which a greater number of general propositions can be made, and those propositions more important, than could be made respecting any other groups into which the same things could be distributed. ... A classification thus formed is properly scientific or philosophical, and is commonly called a Natural, in contradistinction to a Technical or Artificial, classification or arrangement.

It is a bitter thought, how different a thing the Christianity of the world might have been, if the Christian faith had been adopted as the religion of the empire under the auspices of Marcus Aurelius instead of those of Constantine.

Liberty consists in doing what one desires.