Who said "Perseverance is the refusal to accept defeat as final."?

This quote is attributed to Karl Popper.

Perseverance is the refusal to accept defeat as final. - Karl Popper

"Perseverance is the refusal to accept defeat as final."

Karl Popper Perseverance

Philosopher Austrian-British 1902–1994

"The task is not so much to see what no one has yet seen, but to think what nobody has yet thought about that which everybody sees."

"All life is problem solving."

"Science may be described as the art of systematic over-simplification."

"The more you know, the more you realize you know nothing."

"Perseverance is the key to success."

"Don't give up on what you believe in."

"I've been through worse."

"You learn to live with the pain."