Johannes de Villiers Graaff (also known as Jan de Van Graaff or Jannie Graaff) (19 February 1928 – 6 January 2015) was a neoclassical South African welfare economist. Graaff is noted for his work on optimal savings rates, contributions to the creation of the social welfare function and for his 1957 magnum opus Theoretical Welfare Economics. Family and early life Graaff was born in Muizenberg on 19 February 1928 into a wealthy Cape Town Afrikaans family. He was the youngest of Sir David Graaff, 1st Baronet's three children, his eldest brother was Sir De Villiers Graaff, 2nd Baronet. At the age of fifteen he matriculated from Diocesan College with the second highest marks in South Africa. In 1951 he married Lillian Clare Thomson, daughter of Sir George Paget Thomson, and had six children with her. Academia and economics Graaff graduated from the University of Cape Town and then went on to complete his PhD in economics at St John's College, Cambridge in 1950, where he lectured economics until 1953. In 1957 he published Theoretical Welfare Economics, a revised version of his PhD thesis that pioneered the concept of welfare economics. The book had six re-prints in its first ten years and was regarded as a highly important work in the field of Welfare Economics. He left Cambridge due to his dislike of for the politics and infighting of academia and instead bought a farm in the Koue Bokkeveld region of South Africa. His departure from academia led Paul Samuelson to comment that welfare economics would have been vastly different "if Jannie had not decided to go farming". Although he had ostensibly left academia he remained a visiting lecturer at the University of Cape Town and Stellenbosch University. Graaff was President of the Economic Society of South Africa for the period from 1968 to 1969 and was important in supporting the South African Journal of Economics. Graaff made a major contribution to the social welfare function by being the first to derive an equilibrium relationship between equity and national income. Another important contribution made by Graaff was his development of a measure to judge "the well-being of an economy that went beyond the familiar Pareto efficiency criterion: although an economy may be operating efficiently in the sense of utilising all available resources, this may not coincide with the most desired distributional outcome." Post-academic career Graaff played a large role in the