"The toughest thing about success is that you've got to keep on being a success."
"The biggest job we have is to teach a newly hired employee how to fail intelligently. We have to train him to experiment over and over and to keep on trying and failing until he learns what will work."
"I have tried to keep on with my striving because this is the only hope I have of ever achieving anything worthwhile and lasting."
"I do the very best I know how - the very best I can and I mean to keep on doing so until the end."