Quote by Elie Metchnikoff

"The study of the lower organisms is the key to the understanding of man."

"Optimism is a moral duty."

"Life is a process of constant transformation."

"The cell is the unit of life."

"Life is meant to be lived with passion."

"Life is what happens when you're busy making other plans."

"Life is a journey, not a destination."

"Life's too short for regrets."