# Smale's paradox

> English word · Proper noun

## Definitions
1. The non-intuitive fact that it is possible to turn a sphere inside out in a three-dimensional space with possible self-intersections but without creating any crease.

## Etymology
First proven in 1957 by Stephen Smale.

## Source
Compiled from Wiktionary via kaikki.org (CC BY-SA). Data vintage: 2026-05-06.
Canonical page: https://plainspell.com/en/word/smale-s-paradox