Genius is the ability to independently arrive at and understand concepts that would normally have to be taught by another person.

There is no virtue in penance and fasting which waste the body; they are only fanatical and monkish.

Metaphysics is a dark ocean without shores or lighthouse, strewn with many a philosophic wreck.

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

Sincerity is the indispensable ground of all conscientiousness, and by consequence of all heartfelt religion.

It is therefore correct to say that the senses do not err — not because they always judge rightly, but because they do not judge at all.

Genius is the ability to independently arrive at and understand concepts that would normally have to be taught by another person.