““I frankly doubt that.”
“Ah. That is your privilege. But doubt doesn’t alter fact, sir.””

“I doubt I called him illegitimate, sir. I wouldn't use that sort of word. I probably called him a bastard.”

“When you doubt your power, you give power to your doubt.”

“I had no doubts as to the correctness of my own beliefs, that human nature could be altered, that man could be forced to evolve morally.”

“Frankly, we doubt the veracity and seriousness of the United States in regard to achieving results that would be acceptable to both sides in Geneva.”

“Ah, never fear; death could be trusted to show up. No doubt well before she wanted it.”

“If there are still doubts about the truth behind human existence, then the answer to those doubts is the fact that humans cannot control their own destiny.”

“Doubt about the fact that insight wholesomeness consists of simply observing the presently arising mental and physical phenomena is also skeptical doubt. This doubt is so subtle that it is rarely detected but is instead mistaken for investigation. This doubt masquerades as analytical knowledge. The commentary on Netti Yuttihāra explains as follows: "Doubt appears in the guise of investigation."”

“As I said, getting out of the rat race is technically easy. It doesn’t take much education, but those doubts are cripplers for most people.”

“Doubt thou the stars are fire;
Doubt that the sun doth move;
Doubt truth to be a liar;
But never doubt I love.”