“Tell your son to stop trying to fill your head with science — for to fill your heart with love is enough!”

“I don't know anything, but I do know that everything is interesting if you go into it deeply enough.”

“You can recognize truth by its beauty and simplicity.”

“I can live with doubt, and uncertainty, and not knowing. I think it's much more interesting to live not knowing than to have answers which might be wrong.”

“I learned very early the difference between knowing the name of something and knowing something.”

“What I cannot create, I do not understand.”

“Happiness is the final and perfect fruit of obedience to the laws of life.”

“The highest result of education is tolerance.”

“Example is the best lesson there is.”

“Only a man's character is the real criterion of worth.”

“It isn't enough to talk about peace. One must believe in it. And it isn't enough to believe in it. One must work at it.”

“In the long run, we shape our lives and we shape ourselves. The process never ends until we die. And the choices we make are ultimately our own responsibility.”