“When I don’t understand, I have an unbearable itch to know why.”
Source: Have Space Suit—Will Travel (1958), Chapter 7
Help us to complete the source, original and additional information
Robert A. Heinlein 557
American science fiction author 1907–1988Related quotes

“Itch to read, scratch to understand.”
From the ninth book, "The Book of Secrets"
The Pillow Book

De Abaitua interview (1998)
Context: I can understand why magicians have such a high insanity rate. We don’t end well, most of us, it has to be said. Paul Daniels might escape the worst effects, but the rest of us are pretty obviously doomed. Once you step over that line, you are in danger from a lot of stuff. Delusion, obviously, being the main thing.

Manuscript (1903), published in Q.E.D. Book 1, from Q.E.D., and Other Early Writings (1971)

Interview with Bill O'Reilly http://www.politifact.com/truth-o-meter/statements/2011/feb/08/bill-oreilly/bill-oreilly-tells-obama-he-also-asked-bush-about-/ (November 2010), Fox News.
2010s, 2010

On an article by Qunta magazine(when asked: Is there one big question that has always guided you?) https://www.quantamagazine.org/michael-atiyahs-mathematical-dreams-20160303
Context: I always want to try to understand why things work. I’m not interested in getting a formula without knowing what it means. I always try to dig behind the scenes, so if I have a formula, I understand why it’s there. And understanding is a very difficult notion. People think mathematics begins when you write down a theorem followed by a proof. That’s not the beginning, that’s the end. For me the creative place in mathematics comes before you start to put things down on paper, before you try to write a formula. You picture various things, you turn them over in your mind. You’re trying to create, just as a musician is trying to create music, or a poet. There are no rules laid down. You have to do it your own way. But at the end, just as a composer has to put it down on paper, you have to write things down. But the most important stage is understanding. A proof by itself doesn’t give you understanding. You can have a long proof and no idea at the end of why it works. But to understand why it works, you have to have a kind of gut reaction to the thing. You’ve got to feel it.
Keynote speech, Wharton Global Modular Course, May 25, 2015. http://www.inside-rge.com/Sukanto-Tanoto-Entrepreneur-Journey-1
2015