"A worm is a worm, and a man is a man. But if you compare a man to a worm, you will see that a man is only a worm."

"Human beings, having, above all creatures, received the power of reason... need to be aware where nature is unaware. Nature reaches its culmination in humans, but human consciousness has not its essen…"

"I saw a monster today: a two-headed calf. It lived for only an hour, but I dissected it to see if God had given it two souls."

"The natural system will always remain the greatest goal for botanists."

"The method is the soul of science."