Most men use their knowledge only under guidance from others because they lack the courage to think independently using their own reasoning abilities. It takes intellectual daring to discover the truth.
A man who has tasted with profound enjoyment the pleasure of agreeable society will eat with a greater appetite than he who rode horseback for two hours. An amusing lecture is as useful for health as the exercise of the body.
I learned to honor human beings, and I would find myself far more useless than the common laborer if I did not believe that this consideration could impart to all others a value establishing the rights of humanity.
The universal and lasting establishment of peace constitutes not merely a part, but the whole final purpose and end of the science of right as viewed within the limits of reason.
Deaths, births, and marriages, considering how much they are separately dependent on the freedom of the human will, should seem to be subject to no law according to which any calculation could be made beforehand of their amount; and yet the yearly registers of these events in great countries prove that they go on with as much conformity to the laws of nature as the oscillations of the weather.
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?
We come no nearer the infinitude of the creative power of God, if we enclose the space of its revelation within a sphere described with the radius of the Milky Way, than if we were to limit it to a ball an inch in diameter. All that is finite, whatever has limits and a definite relation to unity, is equally far removed from the infinite... Eternity is not sufficient to embrace the manifestations of the Supreme Being, if it is not combined with the infinitude of space.
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.
cruelty to animals is contrary to man's duty to himself, because it deadens in him the feeling of sympathy for their sufferings, and thus a natural tendency that is very useful to morality in relation to other human beings is weakened.