“My mentality is that of a samurai. I would rather commit seppuku than fail.”

“I have made the mistaken assumption - and I will attempt to be better at this - of thinking that because somebody is on Twitter and is attacking me that it is open season. And that is my mistake.”

“I started SpaceX with the expectation of failure.”

“Even if producing CO2 was good for the environment, given that we're going to run out of hydrocarbons, we need to find some sustainable means of operating.”

“Optimism, pessimism, f**k that; we're going to make it happen. As God is my bloody witness, I'm hell-bent on making it work.”

“Even the most eminent persons are subject to the laws of gravity.”

“If your car could travel at the speed of light, would your headlights work?”

“The atom cannot disobey the law. Whether it is the mental or the physical atom, it must obey the law. "What is the use of [external restraint]?"”

“Why should we rise because 'tis light? Did we lie down because t'was night?”

“Every why hath a wherefore.”

“For to define true madness,What is't but to be nothing else but mad?”

“O teach me how I should forget to think (1.1.224)”

“The learned and the studious of thought have no monopoly of wisdom. Their violence of direction in some degree disqualifies them to think truly.”

“Do not craze yourself with thinking, but go about your business anywhere.”