# Quote — George Pólya, How to Solve It

> There was a seminar for advanced students in Zürich that I was teaching and von Neumann was in the class. I came to a certain theorem, and I said it is not proved and it may be difficult. Von Neumann didn't say anything but after five minutes he raised his hand. When I called on him he went to the blackboard and proceeded to write down the proof. After that I was afraid of von Neumann.

- Author: [George Pólya](https://www.leafyquotes.com/george-polya.md)
- Book: [How to Solve It](https://www.leafyquotes.com/george-polya/how-to-solve-it.md)
- Source: [Wikiquote](https://en.wikiquote.org/wiki/George_P%C3%B3lya#How_to_Solve_It_(1945)) ([CC BY-SA 4.0](https://creativecommons.org/licenses/by-sa/4.0/))
- Quote page: https://www.leafyquotes.com/george-polya/how-to-solve-it/there-was-a-seminar

## More from this book

> We need heuristic reasoning when we construct a strict proof as we need scaffolding when we erect a building.

p. 113 — [Quote page](https://www.leafyquotes.com/george-polya/how-to-solve-it/we-need-heuristic.md)

> Euclid's manner of exposition, progressing relentlessly from the data to the unknown and from the hypothesis to the conclusion, is perfect for checking the argument in detail but far from being perfect for making understandable the main line of the argument.

p. 70 — [Quote page](https://www.leafyquotes.com/george-polya/how-to-solve-it/euclids-manner-of-exposition.md)

> To write and speak correctly is certainly necessary; but it is not sufficient. A derivation correctly presented in the book or on the blackboard may be inaccessible and uninstructive, if the purpose of the successive steps is incomprehensible, if the reader or listener cannot understand how it was humanly possible to find such an argument....

p. 207 — [Quote page](https://www.leafyquotes.com/george-polya/how-to-solve-it/to-write-and.md)