Peter John Freyd (/fraɪd/; born February 5, 1936) is an American mathematician, a professor at the University of Pennsylvania, known for work in category theory and for founding the False Memory Syndrome Foundation.

Freyd obtained his Ph.D. from Princeton University in 1960; his dissertation, on Functor Theory,[2] was written under the supervision of Norman Steenrod and David Buchsbaum.

He was the author of the foundational book Abelian Categories: An Introduction to the Theory of Functors (1964).

In addition, Freyd's name is associated with the HOMFLYPT polynomial of knot theory, and he and Andre Scedrov originated the concept of (mathematical) allegories.

[3] Freyd and his wife Pamela founded the False Memory Syndrome Foundation in 1992,[4][5] after Freyd was accused of childhood sexual abuse by his daughter Jennifer.