This can never become popular, and, indeed, has no occasion to be so; for fine-spun arguments in favour of useful truths make just as little impression on the public mind as the equally subtle objections brought against these truths. On the other hand, since both inevitably force themselves on every man who rises to the height of speculation, it becomes the manifest duty of the schools to enter upon a thorough investigation of the rights of speculative reason, and thus to prevent the scandal which metaphysical controversies are sure, sooner or later, to cause even to the masses.

Two things fill the mind with ever-increasing wonder and awe, the more often and the more intensely the mind of thought is drawn to them: the starry heavens above me and the moral law within me... Morality is not properly the doctrine of how we may make ourselves happy, but how we may make ourselves worthy of happiness.

Rules for Happiness: something to do, someone to love, something to hope for.

Among all nations, through the darkest polytheism glimmer some faint sparks of monotheism.

All the interests of my reason, speculative as well as practical, combine in the three following questions: 1. What can I know? 2. What ought I to do? 3. What may I hope?

If it were possible for us to have so deep an insight into a man's character as shown both in inner and in outer actions, that every, even the least, incentive to these actions and all external occasions which affect them were so known to us that his future conduct could be predicted with as great a certainty as the occurrence of a solar or lunar eclipse, we could nevertheless still assert that the man is free.

After death the soul possesses self-consciousness, otherwise, it would be the subject of spiritual death, which has already been disproved. With this self-consciousness necessarily remains personality and the consciousness of personal identity.