Hans Jürgen Eysenck (/ˈaɪzɛŋk/ EYE-zenk; 4 March 1916 – 4 September 1997) was a German-born British psychologist. 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 most frequently cited living psychologist in peer-reviewed scientific journal literature.
Eysenck's research included claims that certain personality types had an elevated risk of cancer and heart disease and research on IQ scores and race (first published in 1971), which were a significant source of controversy. 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 coauthored with Ronald Grossarth-Maticek to be "incompatible with modern clinical science", with 26 of the joint papers considered suspect. Fourteen papers were retracted in 2020, and over 60 statements of concern were issued by scientific journals in 2020 about publications by Eysenck. David Marks and Rod Buchanan, a biographer of Eysenck, have argued that 87 publications by Eysenck should be retracted.
