Immanuel Kant

"The death of dogma is the birth of morality."

"Settle, for sure and universally, what conduct will promote the happiness of a rational being."

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

"Science is organized knowledge. Wisdom is organized life."

"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?"

"Act only according to that maxim whereby you can at the same time will that it should become a universal law."