Fact and Fiction in Psychology

Eysenck argues that psychology should be held to the standards of a natural science: claims must be empirically testable and falsifiable. The book's central mechanism is the contrast between laboratory evidence and speculative systems. He rejects psychoanalysis as unfalsifiable fiction, devoting a chapter titled 'Little Hans or Little Albert?' to a damning review of Freudian theory and practice, citing Wolpe and Rachman's studies that used Freud's own data to show his claims were inconsistent with facts . He also dismisses psychiatric neglect of behavior therapy, which he presents as the empirically validated alternative .

Eysenck's Demon is a hypothetical physiological mechanism introduced to explain the biological basis of introversion and extraversion, named by analogy to Maxwell's Demon in physics . It models how individual differences in cortical arousal—mediated by the ascending reticular activating system—produce the behavioral patterns associated with each dimension. This is the same arousal theory Eysenck developed more fully in The Biological Basis of Personality (1967). In Fact and Fiction, the Demon serves as a popular-level illustration of how psychological constructs can be grounded in physiological mechanisms rather than left as descriptive labels.

A 1966 PsycCRITIQUES review noted that Eysenck sets his record straight, declaring he is 'not a controversial figure, or if he is, he does not regret it' . The reviewer observed that the book 'well demonstrated' the application of learning theory to behavior therapy and criticized its neglect by psychiatrists, concluding it 'should be well pondered by all who look forward to psychology possessing a substantial logos' . A review in the Journal of the American Medical Association was more critical, describing Eysenck as riding 'his hobby-horses almost to extinction' .

The book devotes two pages (194–195) to the morality of so-called 'treatment' of homosexuality, which was illegal in Britain at the time of writing . Eysenck discusses aversion therapy as a method for altering sexual orientation. A 2017 Goodreads reviewer described Eysenck as 'horrifically homophobic,' noting that the material would have fueled the use of shock therapy to 'cure' homosexuality and expressing shock at this finding . The book predates the depathologization of homosexuality and reflects the clinical assumptions of its era, which later research and ethical standards rejected.

Fact and Fiction is the third in a loosely connected trilogy of Penguin books aimed at general readers, following Uses and Abuses of Psychology and Sense and Nonsense in Psychology . It was later expanded into a quartet with Psychology Is about People . The trilogy shared a common purpose: demystifying psychology and advocating scientific rigor against loose thinking . Fact and Fiction is the most polemical of the group, with its extended attack on psychoanalysis and its advocacy of behavior therapy as the empirically validated alternative.

Fact and Fiction in Psychology was first published in 1965 by Penguin Books in Harmondsworth and Baltimore, as a Pelican paperback (A696) . WorldCat records 48 editions and printings, including reprints in 1970, 1972, 1974, 1975, 1977, and 1980 . It was translated into Portuguese as Verdades e mentiras da psicologia (1957, Ulisseia) , into Japanese by Iwawaki Saburō (Seishin Shobō, 1968) , and into Spanish (1973) . The original Penguin edition runs approximately 300 pages.