I have not failed. I’ve just found 10,000 ways that won’t work. (Thomas Alva Edison)

Blessed is the man, who having nothing to say, abstains from giving wordy evidence of the fact. (George Eliot)

I am ready to meet my Maker. Whether my Maker is prepared for the great ordeal of meeting me is another matter. (Sir Winston Churchill)

Each problem that I solved became a rule which served afterwards to solve other problems. (Rene Descartes, Discours de la Methode)