During their lifetimes, every man and woman will stumble across a great opportunity. Sadly, most of them will simply pick themselves up, dust themselves down and carry on as if nothing ever happened. – Winston S. Churchill.
One sticks to an opinion because he prides himself on having come to it on his own, and another because he has taken great pains to learn it and is proud to have grasped it: and so both do so out of vanity. ― Friedrich Nietzsche.