Quote by Elie Metchnikoff

"Man can adapt himself to anything, but he cannot adapt himself to anything without effort."

"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."

"Friendship is built on trust and honesty."

"True friendship is worth more than gold."

"Good friends are like stars, always there even when you can't see them."

"Friendship means sacrifice."