# Quote — George Pólya, How to Solve It

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

- 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)
- Page: 113
- 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/we-need-heuristic

## More from this book

> 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)

> The cookbook gives a detailed description of ingredients and procedures but no proofs for its prescriptions or reasons for its recipes; the proof of the pudding is in the eating. … Mathematics cannot be tested in exactly the same manner as a pudding; if all sorts of reasoning are debarred, a course of calculus may easily become an incoherent inventory of indigestible information.

p. 219 — [Quote page](https://www.leafyquotes.com/george-polya/how-to-solve-it/the-cookbook-gives.md)