"It is not the critic who counts: not the man who points out how the strong man stumbles or where the doer of deeds could have done better. The credit belongs to the man who is actually in the arena, whose face is marred by dust and sweat and blood, who strives valiantly, who errs and comes up short again and again, because there is no effort without error or shortcoming, but who knows the great enthusiasms, the great devotions, who spends himself for a worthy cause; who, at the best, knows, in the end, the triumph of high achievement, and who, at the worst, if he fails, at least he fails while daring greatly, so that his place shall never be with those cold and timid souls who knew neither victory nor defeat." - Theodore Roosevelt (speech at the Sorbonne, Paris, April 23, 1910)

"Twenty years from now you will be more disappointed by the things that you didn’t do than by the ones you did do.
So throw off the bowlines.
Sail away from the safe harbor.
Catch the trade winds in your sails.
Explore. Dream. Discover." - Mark Twain

“Don’t tell me it’s impossible, tell me you can’t do it. Tell me it’s never been done. Because the only real laws in this world–the only things we really know–are the two postulates of relativity, the three laws of Newton, the four laws of thermodynamics, and Maxwell’s equation–no, scratch that, the only things we really know are Maxwell’s equations, the three laws of Newton, the two postulates of relativity, and the periodic table. That’s all we know that’s true. All the rest are man’s laws…” - Dean Kamen (Inventor of the Segway and generally bright guy)