The term "negative utilitarianism" was introduced by R. N. Smart in his 1958 reply to Karl Popper's book[9] The Open Society and Its Enemies, published in 1945.[10] In the book, Popper emphasizes the importance of preventing suffering in public policy.[11] The ideas in negative utilitarianism have similarities with ancient traditions such as Jainism and Buddhism.[12] Ancient Greek philosopher Hegesias of Cyrene has been said to be "one of the earliest exponents of NU [Negative Utilitarianism]."[13] In more recent times, ideas similar to negative utilitarianism can be found in the works of 19th century psychologist Edmund Gurney who wrote: