Who said "Kindness costs nothing but yields infinite returns."?

This quote is attributed to Professor X.

Kindness costs nothing but yields infinite returns. - Professor X

"Kindness costs nothing but yields infinite returns."

Professor X Kindness

"Mutants. Since the discovery of their existence they have been regarded with fear and suspicion by humanity."

"We are the future, Charles, not them. They no longer matter."

"Just because someone stumbles and loses their way doesn't mean they're lost forever."

"What we have to fear is fear itself."

"A good man treats his wife with respect."

"Kindness always comes back around."

"The power of a smile can change everything."

"Kindness is weakness to some. Not to me."