Hans Eysenck, German-English psychologist and theorist (d. 1997)

Hans Jürgen Eysenck (; 4 March 1916 – 4 September 1997) was a German-born British psychologist who spent his professional career in Great Britain. He is best remembered for his work on intelligence and personality, although he worked on other issues in psychology. At the time of his death, Eysenck was the living psychologist most frequently cited in the peer-reviewed scientific journal literature.Eysenck's research purported to show that certain personality types had an elevated risk of cancer and heart disease. Scholars have identified errors and suspected data manipulation in Eysenck's work, and large replications have failed to confirm the relationships that he purported to find. An enquiry on behalf of King's College London found the papers by Eysenck to be "incompatible with modern clinical science".In 2019, 26 of his papers (all coauthored with Ronald Grossarth-Maticek) were considered "unsafe" by an enquiry on behalf of King's College London. Fourteen of his papers were retracted in 2020, and journals issued 64 statements of concern about publications by him. Rod Buchanan, a biographer of Eysenck, has argued that 87 publications by Eysenck should be retracted.During his life, Eysenck's claims about IQ scores and race, first published in 1971, were a significant part of his public reputation. Eysenck believed IQ scores were hereditary and genetically influenced by biological race. He had cited studies which claimed black children's average IQ score was 12 points lower than white children. Eysenck's writing on this belief was used as justification for discriminatory schooling in Britain in the 1970s. Eysenck's beliefs on race have subsequently been disproved, and are no longer accepted as part of mainstream psychology.