Animals... are there merely as a means to an end. That end is man.

One who makes himself a worm cannot complain afterwards if people step on him.

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.

Parents usually educate their children merely in such a manner than however bad the world may be, they may adapt themselves to its present conditions. But they ought to give them an education so much better than this, that a better condition of things may thereby be brought about by the future.

Nature, when left to universal laws, tends to produce regularity out of chaos.

The hand is the visible part of the brain.

The science of mathematics presents the most brilliant example of how pure reason may successfully enlarge its domain without the aid of experience