# Quote — Henri Poincaré, Science and Method

> The greatest chance is the birth of a great man. It is only by chance that two reproductive cells, of different sexes, met, each containing precisely those mysterious elements whose mutual reaction was to produce genius. We will agree that these elements must be rare and that their meeting is even rarer. That it would have taken little to deviate the spermatozoon that carried them from its course; it would have been enough to deviate it by a tenth of a millimeter and Napoleon would not have been born and the destiny of a continent would have been changed. No other example can better explain the true nature of chance.

- Author: [Henri Poincaré](https://www.leafyquotes.com/henri-poincare.md)
- Book: [Science and Method](https://www.leafyquotes.com/henri-poincare/science-and-method.md)
- Original (fr): Le plus grand hasard est la naissance d’un grand homme. Ce n’est que par hasard que se sont rencontrées deux cellules génitales, de sexe différent, qui contenaient précisément, chacune de son côté, les éléments mystérieux dont la réaction mutuelle devait produire le génie. On tombera d’accord que ces éléments doivent être rares et que leur rencontre est encore plus rare. Qu’il aurait fallu peu de chose pour dévier de sa route le spermatozoïde qui les portait ; il aurait suffi de le dévier d’un dixième de millimètre et Napoléon ne naissait pas et les destinées d’un continent étaient changées. Nul exemple ne peut mieux faire comprendre les véritables caractères du hasard.
- Source: [Wikiquote](https://en.wikiquote.org/wiki/Henri_Poincar%C3%A9#Science_and_Method_(1908)) ([CC BY-SA 4.0](https://creativecommons.org/licenses/by-sa/4.0/))
- Quote page: https://www.leafyquotes.com/henri-poincare/science-and-method/the-greatest-chance

## More from this book

> Logic sometimes breeds monsters. For half a century there has been springing up a host of weird functions, which seem to strive to have as little resemblance as possible to honest functions that are of some use. No more continuity, or else continuity but no derivatives, etc. More than this, from the point of view of logic, it is these strange functions that are the most general; those that are met without being looked for no longer appear as more than a particular case, and they have only quite a little corner left them. Formerly, when a new function was invented, it was in view of some practical end. Today they are invented on purpose to show our ancestors' reasoning at fault, and we shall never get anything more than that out of them.

p. 139 — [Quote page](https://www.leafyquotes.com/henri-poincare/science-and-method/logic-sometimes-breeds.md)

> It is because simplicity and vastness are both beautiful that we seek by preference simple facts and vast facts; that we take delight, now in following the giant courses of the stars, now in scrutinizing the microscope that prodigious smallness which is also a vastness, and now in seeking in geological ages the traces of a past that attracts us because of its remoteness.

p. 23 — [Quote page](https://www.leafyquotes.com/henri-poincare/science-and-method/it-is-because.md)

> Every definition implies an axiom, since it asserts the existence of the object defined. The definition then will not be justified, from the purely logical point of view, until we have proved that it involves no contradiction either in its terms or with the truths previously admitted.

p. 131 — [Quote page](https://www.leafyquotes.com/henri-poincare/science-and-method/every-definition-implies.md)