Quote by Popper, Karl
"Courage is the greatest of all virtues, because if you haven't courage, you may not have an opportunity to use any of the others."
More from Popper, Karl
"The true paradox is only the paradox that is true."
"I may not be smarter than you, but I can admit when I'm wrong."
"The more we learn about the world, and the deeper our learning, the more conscious, clear and definite will be our knowledge of what we do not know."
"Science may be described as the art of systematic over-simplification."