Who said "Doubt is important. It is the key to all progress."?

This quote is attributed to Albert Einstein.

Doubt is important. It is the key to all progress. - Albert Einstein

"Doubt is important. It is the key to all progress."

Albert Einstein Motivation

Theoretical Physicist German-American 1879–1955

"Life is like riding a bicycle. To keep your balance, you must keep moving."

"Imagination is more important than knowledge. Knowledge is limited; imagination encircles the world."

"In the middle of difficulty lies opportunity."

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

"I believe in working hard for what you want."

"Never underestimate the power of determination."

"I don't need a reason to fight."

"The most important thing is the mission. Nothing else matters."