Ronald Bon de Sousa Pernes (born 1940 in Switzerland) is an Emeritus Professor at the Department of Philosophy of the University of Toronto which he joined in 1966. He is best known for his work in philosophy of emotions, and has also made contributions to philosophy of mind and philosophy of biology. He was elected a fellow of the Royal Society of Canada in 2005.
De Sousa possesses both UK and Canadian citizenship. Educated in Switzerland and England, he took his B.A. at New College, Oxford University in 1962, and his Ph.D. at Princeton University in 1966. He has contributed to and is frequently cited in the Stanford Encyclopedia of Philosophy.