Experience without theory is blind, but theory without experience is mere intellectual play.

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

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.

Every human being should always be treated as an end and never as a mere instrument.

If an offender has committed murder, he must die. In this case, no possible substitute can satisfy justice. For there is no parallel between death and even the most miserable life, so that there is no equality of crime and retribution unless the perpetrator is judicially put to death.

Morality is not properly the doctrine of how we may make ourselves happy, but how we may make ourselves worthy of happiness.

Beauty presents an indeterminate concept of Understanding, the sublime an indeterminate concept of Reason.