Sir Alfred Bray Kempe FRS (6 July 1849 – 21 April 1922) was a mathematician best known for his work on linkages and the four colour theorem.

He was educated at St Paul's School, London and then studied at Trinity College, Cambridge, where Arthur Cayley was one of his teachers.

This direct connection between linkages and algebraic curves is now called Kempe's universality theorem.

[6] In 1879 Kempe wrote his famous "proof" of the four colour theorem, shown incorrect by Percy Heawood in 1890.

Kempe (1886) revealed a rather marked philosophical bent, and much influenced Charles Sanders Peirce.