once two dejected assistants of Thomas Edison said: "we've just completed our seven hundredth experiment and we still don't have the answer. we have failed,.."
"no, my friends, you haven't failed,.." replied Mr. Edison. "it's just that we know more about this subject than anyone else alive. and we are closer to finding the answer because now we know seven hundred things not to do. don't call it a mistake. call it an 'education'.
Dare to Fail 4th Ed.