Henry Sidgwick (; 31 May 1838 – 28 August 1900) was an English utilitarian philosopher and economist. He was one of the founders and first president of the Society for Psychical Research and a member of the Metaphysical Society, and promoted the higher education of women. His work in economics has also had a lasting influence. He also founded Newnham College in Cambridge in 1875. Newnham College is a women-only constituent college of the University of Cambridge, England. It was the second Cambridge college to admit women after Girton College. The co-founder of the college was Millicent Garrett Fawcett. He joined the Cambridge Apostles intellectual secret society in 1856.