Forsyth, Andrew Russell (1858–1942)

Scottish mathematician. His Theory of Functions (1893) introduced the main strands of European mathematical study to British mathematicians. Bringing together the work of all the various schools in a single volume, the book completely changed the nature of mathematical thinking.

He formulated a theorem that generalized a large number of identities between double theta functions; because this work was also carried out independently yet simultaneously by Henry Smith (1826–1883), the theorem is now called the Smith–Forsyth theorem. Forsyth also studied languages, enabling him to translate the works of others and to introduce their ideas to the UK. His Theory of Functions stimulated such rapid developments in mathematics that Forsyth was soon left behind.

Forsyth was born in Glasgow and studied at Cambridge. He was professor at Liverpool College 1882–84, but spent most of his career at Cambridge. From 1913 to 1923 he was professor at Imperial College, London.