# nLab involution

An involution is an endomorphism whose square is the identity morphism. Such an endomorphism must be an automorphism; indeed, it is its own inverse.

Where this makes sense, an anti-involution is an antihomomorphism instead of a homomorphism (so an antiendomorphism and necessarily an antiautomorphism).

Revised on August 24, 2012 07:12:02 by Toby Bartels (98.19.40.130)