The centenary of a maverick

Hans J. Eysenck (1916–1997) enjoyed an extraordinary life in British psychology, much of it played out in the limelight of public attention. His fame and influence extended beyond the shores of these isles, to encompass the globe. He inspired generations of psychologists, many of whom were enthralled by his popular books that made psychology seem so vital, relevant and even urgent. His was an open invitation: arise from the supine position on the analytical couch, leap out from the comfort of the philosophical armchair, and visit the psychology laboratory – one chapter in Fact and Fiction in Psychology (Eysenck, 1965a) is titled, 'Visit to a psychological laboratory'. His easy-to-understand causal theories of 'what makes people tick' (exposing the inner working of the human clock) were especially fascinating to an inquisitive public. He also courted controversy: his style of advocating change and some of the positions he took, especially on politically charged issues like race and IQ, attracted criticism of his work, and of him.

4 March 2016 would have been Hans Eysenck's 100th birthday. This offers a timely opportunity to reflect upon the growth of psychology over the last century and Eysenck's role in it, including an evaluation of the controversial aspects of his career. Perhaps more than any other British psychologist, his story is its story.

A very public psychologist

But first, the fame Eysenck acquired during his life needs highlighting. He adored the attention of the general audience and relished being the public face (and, somewhat ironically, the gentle German voice) of British psychology. Such was the interest, he was interviewed in 1990 as part of the Face to Face television series, which included interviews with other luminaries: actors such as Kirk Douglas, film directors including Steven Spielberg, and comedians like Billy Connolly. In 1994 a whole BBC programme was devoted to him in the Heretics series. Eysenck was also in demand by popular magazines, from the middle-brow Reader's Digest to the top-shelf Playboy and Penthouse (where some of his most insightful interviews may be found: e.g Cohen, 1970).

Echoing similar sentiments to Diana, Princess of Wales, who died just a few days earlier than him, Eysenck's obituary in The Guardian called him the 'People's psychologist'. Somewhat like Diana, people seemed to identify with him, and it was not always clear exactly why – in their very different, and less than flawless, ways they touched on issues that other people considered important.

All of this was quite extraordinary for an academic psychologist.

Eysenck's contributions were many, varied and significant, including: the professional development of clinical psychology; the slaying of the psychoanalytical dragon; pioneering behaviour therapy and, thus, helping to usher in the era of cognitive behavioural therapy (although he had little time for the 'cognitive' part); and developing a highly influential model of the biological nature of personality and individual differences, which now provides the general framework for personality psychology today. As the years pass, the rapidly developing field of personality neuroscience started to uncover the biologically grounded corporeal nature of the traits that Eysenck envisions as early as the 1940s (e.g. DeYoung et al., 2010). What Eysenck set out to do was not only describe personality but also explain it – given the resistance to such biological accounts in the 1950s/60s, as Dick Passingham notes, this was 'very brave' (Corr, 2016, p.332). Nowadays, cognitive neuroscience is all the rage, but back then it was seen by many people as little more than a scientifically sterile dogmatic approach with no future. Eysenck's pioneering work in the science of personality assures him a place in the history books.

On their own, these are remarkable achievements. But they are far from the whole story. From the 1950s to the 1990s, Eysenck built one of the world's leading psychology departments at the Institute of Psychiatry (IoP; now the Institute of Psychiatry, Psychology and Neuroscience, IoPPN, at King's College London), which fast became a foremost centre of research excellence and the handmaiden of scientific clinical psychology. Demonstrating his foresight, from the early days, Eysenck wanted a three-year clinical doctorate, with the first year entailing psychiatric experience and the following two years research training – it took many more years for the MSc in Clinical Psychology to become the Clinical Doctorate we have today and to which so many psychology graduates aspire.

William Yule (2015; see also Yule, 1998) gives a very favourable view of Eysenck's contribution to the development of clinical psychology, recalling how Eysenck and Aubrey Lewis went to the University of London to get course approval. This they received at the meeting, only later to discover that Cyril Burt had pressurised the committee secretary to record a 'reject' decision. Eysenck and Lewis had to troop back to Senate House to get the approval for a second, and final, time. (Jack Rachman, similarly, recounts the vital role played by Eysenck in the early days of clinical psychology, and also behaviour therapy; see Corr, 2016, pp.300–301.) These major developments took place in the less than auspicious surroundings of the newly formed IoP, which resided over two floors of a private wing of the Maudsley Hospital with bathrooms and kitchens serving as testing rooms. This was very much a time of 'make do', and resourcefulness of the Eysenck kind was much needed.

Less well known, Eysenck may be credited with establishing the rationale for evidence-based therapy – as Dick Passingham notes, 'We owe it to Hans, evidence based medicine' (Corr, 2016, p.332). Following Eysenck's 'controversial' 1952 paper on the lack of evidence for the effectiveness of psychotherapy, it was recognised that the literature should be properly summarised from a statistical point of view and meta-analysis was born (Smith & Glass, 1977) – these authors were frustrated that 'Most academics have read little more than Eysenck's (1952, 1965[b]) tendentious diatribes…' – clearly out of a negative can come a positive! True to form, Eysenck (1994) later criticised the uses to which meta-analysis is put, calling it 'mega-silliness' when used merely to summarise poorly conceived and conducted empirical studies. He quoted Ernest Rutherford as saying: 'When you needed statistics to make your results significant, you would be better off doing a better experiment.' Most certainly, Eysenck may well be credited with the call that psychotherapy should be empirically evaluated – although commonplace today, back in the 1950s, this seemed an extraordinary, and quite unreasonable, demand.

Reputation and recognition

Such were Eysenck's achievements, awards and honours should be expected to come in quick succession. Not so though in Britain, despite his fame and reputation in the international psychology community. As a matter of fact, he was way ahead of other British psychologists in terms of fame and citations. This fact is not appreciated enough today. According to Haggbloom and colleagues' (2002) analysis of eminence in 20th-century international psychology, Eysenck was the third most cited psychologist (after Freud and Piaget – no other British psychologist even appears in the top 25); their survey of international psychologists places him 24th (again no other British psychologist appears on this top 25 list); and by a ranking of publications, awards, distinctions, etc. he was ranked 13th – the next British psychologist appearing in this list, Donald Broadbent, was way down this list at 54th.

These facts make it all the more remarkable that, despite attempts by colleagues (notably his successor at the IoP Jeffrey Gray), he was denied a Fellowship of the British Psychological Society (BPS), and was never considered for a Fellowship of the Royal Society, which according to Patrick Rabbitt, 'he deserved for his best work' (Corr, 2016, p.291). As a result of his choice of topics to study and his style – often of an abrasive nature in print, but never in person – he accumulated too many enemies, many of whom were less than willing to forgive and forget. However, after his death, the BPS established the Hans Eysenck Memorial Lecture (although, unlike other awards, in recent times this seems to have fallen into abeyance). Although Eysenck was shunned by the psychology establishment in Britain, he was feted in the USA with the award of several distinctions from the American Psychological Association (APA) and the American Psychological Society (APS).

In a real sense, Eysenck was always an outsider; during WWII a legal one and, then later, a psychological one. In academia, this started with Cyril Burt's opinion that he was nothing more than a German Jewish upstart on the make, and the ringleader of a 'Jewish Plot' at the Maudsley (Buchanan, 2010) – all very ironic, because Eysenck never considered himself Jewish, as neither of his parents were of this religious persuasion. The parents of his maternal grandmother were though – in fact, his father, Eduard, did very well under the Nazis, and during his teenage years the young Eysenck could have expected equal favour. But, this was not to be because he hated the Nazis and everything for which they stood. He voted with his feet, leaving Germany, in 1934, at the age of 18, first, and briefly, for France and then London where he spent the rest of his life.

A quote by Bill Yule sums up nicely, My overall view is that Hans made a great contribution to UK psychology. However, he was an outsider from the start. Initially Burt promoted him as a gifted protégé but as soon as he showed some independence, he saw him as a rival. He is on record as saying it was not British for a student to be publishing so much! The establishment (i.e. Oxbridge) were jealous of his facility to write clearly and never gave him the credit he deserved. (Personal communication, 14 October 2015; quoted with permission)

The art of controversy

'Controversy!' – how better to stall debate. In too many people's eyes, this adjective defined Eysenck. In his impressive biography, aptly named Playing with Fire, Buchanan (2010; for a summary, see Buchanan, 2011, noted that, increasingly during Eysenck's later years, the considerable credits he had accumulated during his earlier remarkable career seemed – at least, to some people – to be frittered away on marginal, and as they turned out, largely futile scientific pursuits.

As his son Michael Eysenck (2011; see also 2013) stated, If only my father had focused his research more on behavioural genetics rather than wasting his time tilting at an endless succession of windmills!

Well known to the general public are Eysenck's pronouncements. On these topics there was little empirical research of his own – on such controversial subjects as (a) race, IQ and education, (b) smoking, cancer and personality, and (c) intelligence, social class and inequality; and, then, there were his dabblings in the fringe fields of astrology and parapsychology. Much of this work raised eyebrows in the academic community, and sometimes fists in the lecture theatre (e.g. at a disrupted lecture at the London School of Economics), and achieved little of lasting value. They most certainly tarnished his reputation, if not his legacy.

To illustrate the complexity of Eysenck's views, consider his collaboration with Grossarth-Maticek, and the extraordinary claims of their research (which Eysenck helped write up for publication). This included the development and test of a form of psychotherapy that seemed to reduce significantly the probability of developing cancer and coronary heart disease. Using the same therapy, evidence was also presented that seemed to show that it could also reduce (according to the data, eliminate) social prejudice (for a discussion of this literature, see Corr, 2016; Buchanan, 2010).

In the midst of raised eyebrows and flying academic feathers, real scientific issues were, and still are, at stake. For example, the relationship between psychology and medical disorders is a highly important one, and it should be no surprise if, as Eysenck always insisted, personality played a role (e.g. being vulnerable to stress and, thereby, having an impaired immune system; see Chapman et al., 2013). Indeed, recently, there is also evidence that people can die of a metaphorical broken heart (Carey et al., 2014). Eysenck's interests in psychosomatic medicine reflected his non-Cartesian (monist) view of the mind–body, which extended to social concerns that he considered to be largely psychological in nature and, thus, in need of psychology treatment (e.g. the effects of sex and violence in the media; Eysenck & Nias, 1978). But again in such areas he was treading on political toes (e.g. criticising variously: the alleged benefits of the 'permissive society'; progressive education with the dismantling of the grammar school system; ignoring intelligence differences when accounting for the existence of social class; sex differences in personality and intelligence; and so on). Eysenck's lack of recognition in the Honours List – which he might have expected for his outstanding contribution to British psychology – stands as a warning to those who hope for a token of public recognition, that meddling in 'controversial' areas is a little more than frowned upon in the world of political patronage.

As the case of smoking and cancer shows, Eysenck took the role of a scientific advocate. He wanted to win the (cold) logical argument and was less interested in the (hot) evidential debate. In these ways, he was playing a different intellectual game to many other participants and, for this reason, they so often could not see eye-to-eye. Reflecting his own contradictory psychology (discussed in Corr, 2016), Eysenck was never one to weigh unpassionately the 'probability of the evidence': his stamp of (dis)approval was all over the conclusions he reached (e.g. the corrosive effects of media sex and violence; see Corr, 2016, p.176). This was especially apparent in the case of smoking and cancer. For example, the logical argument that 'smoking does not kill' (at least, as Eysenck framed it) is valid, but it ignores the weight of evidence, which is now overwhelming (e.g. Banks et al., 2015) and in Eysenck's day compelling (see Richard Peto's comments; Corr, 2016, pp.321–332). However, Eysenck's purely logical points are important (relating to necessary and sufficient conditions; see Corr, 2016, pp.232–234): they leave open the causal door on which the opportunity for future research findings may yet come knocking to show that dispositional factors (e.g. personality) are involved in the initiation, continuation and cessation of smoking – and even in the probability of developing cancer. Can we be sure that these factors are not important?

Time sometimes resolves such issues. When Eysenck was shouted down in 1958 by the audience at the Royal Medico-Psychological Association (RMPA), when he denounced psychoanalysis and advocated behaviour therapy, he was being 'controversial' and 'provocative', but as Dick Passingham (in Corr, 2016, p.87) notes, 'The Psychiatrists were wrong'. Should Eysenck have been silenced then, or even sacked as some psychiatrists at the Maudsley demanded as they marched, pell-mell, off to the office of Aubrey Lewis (the Dean of the Institute of Psychiatry)?

In all of these debates, to understand Eysenck fully, it is necessary to know of the entertainment side of him. He was a performer. As he noted (Eysenck, 1990), 'a lecturer need not become less intellectual and scientific for also being entertaining!'. He very much followed in the footsteps of his mother (a famous pre-WWII screen actress – screen name, Helga Molander), with whom he starred in a film as a child, his father (a high-class conferencier – cabaret raconteur), and maternal grandmother (opera singer) who raised him in Berlin. There are also parallels to be drawn between Eysenck's style of engagement and those of 'shocking' and 'sensational' artists (Corr, 2016). It was never just about the science with Eysenck!

Psychology and politics

Perhaps unseemly to mention in the current climate of political apathetic cynicism, Eysenck's work and subsequent reputation were affected by political currents. As he stated in 1990, 'I always had from the beginning the hope that psychological research might be used to improve the human fate, and to find answers to the numerous social problems that beset us', adding 'Our troubles are very largely psychological – i.e., due to "human nature", unreformed and uncontrolled'. Unavoidably, his work ventured into the political arena, and why should psychology not?

But there was another political influence much closer to home. Starting in the 1940s (Eysenck, 1944, 1947, 1950) Eysenck wrote extensively and, as historical events unfolded, persuasively on the personality types that populate the extreme right and left wings of politics. His views were outlined in the Psychology of Politics (1954/1999), which highlighted evidence that the tough-minded include both fascists on the right and communists on the left (see Eysenck & Coulter, 1972) – this personality type relates to an aggressive and dogmatic style. Later Eysenck found that approximately half the variance in this measure is genetic in nature (Eaves & Eysenck, 1974).

Now these ideas were expounded at a time when 'Uncle Joe' Stalin was still enjoying a good press in Britain, and it was common for intellectuals to have communistic leanings or to be card-carrying members of the Party. Here we are talking, not of the treacherous 'Cambridge Five' types, but honourable psychologists of high principles with a desire to affect social change (and many did, for example Jack Tizard's work in mental retardation research and policy). The fact is that many of the leading figures in clinical psychology at the Maudsley (see photo) were communists (notably Monte Shapiro, Barbara and Jack Tizard, Ann and Alan Clarke, Neil O'Connor, as well as the psychiatrist Max Hamilton – a fascinating account is given by Parsons, 1990) and members of the Communist Party Psychologists' group who met regularly around south London. To give a flavour of these times, Shapiro (1948, quoted in Parsons 1990, p.345) considered mental testing as important in uncovering '…the social and biological nature of human ability with a capitalist society, and how it will change under Socialism'.

All of these psychologists were to fall out with Eysenck, and, although it cannot be known for certain, it is highly likely that his views on the unpleasant nature of communism would not have been absent as an influence. Many other psychologists remained loyal to his scientific cause, and to him as the figurehead of a certain brand of psychology (built around a science of individual differences with wide-ranging applications).

In these politically charged times, many people were disappointed by Eysenck's unwillingness to tie his ideas firmly to the Marxist flagpole. During McCarthyism in the USA in the early to mid-1950s – and a lesser form of it in Britain – communists were under sustained attack and some critics had it in for him, most notably Rokeach and Handley (1956) and Christie (1956). As documented by their letters (Buchanan, 2010. p.2), Rokeach and Christie wanted to 'shaft Eysenck' – I shall leave the psychoanalytical interpretation of the remark to those better qualified to comment. Indeed, Rokeach wrote to Christie, 'The major goal we had set ourself [sic] was to discredit Eysenck's reputation as a scientific investigator because we had come to the conclusion that he is not' – once again, there is a potent mix of scientific, political and personal antipathy towards the portmanteau caricature of Eysenck.

This was also around the time when the rumour mill started working overtime to insinuate that Eysenck was engaged in academic malpractice, the more serious whispered accusations never finding a footing in fact – although there is evidence of carelessness and the favouring of research findings that supported his preferred theoretical positions (discussed in Corr, 2016, pp.269–274). The lack of official recognition and honours may have been in no small measure the result of this concerted campaign to 'shaft' Eysenck – in this respect, Rokeach and others succeeded in their self-avowed aim. Ironically, Rokeach (1973, p.186) was later to develop his own conceptual scheme of human values, which he stated, 'most closely resembles Eysenck's (1954) hypothesis'.

Centennial reflections

Some of the disconcerting aspects of Eysenck's work reflect schisms in psychology itself, and this is nowhere more apparent than in his main scientific interest of personality (including intelligence). Eysenck is requiring this underdeveloped, and often wayward, academic discipline to take seriously the idea that personality traits reflect intra-personal states of motivation, emotion, etc., whilst at the same time requiring it to adhere to the main principles of behaviourism that emphasised the centrality of observable, preferably experimental, behaviour. Eysenck saw how this gulf could be spanned, and he had the necessary conceptual equipment to set about construction. However, for many psychologists it was a bridge too far – or, at least, a far too shaky one on which to rest the future of psychology.

All of this speaks to the nature of psychology. Few would dispute the claim that, although a vibrant field of research and practice, psychology remains fragmented, composed of an often loosely connected collection of disparate areas, containing no universally accepted theoretical foundations (e.g. Banyard, 2015). Eysenck recognised this fact and sought to develop a paradigm for psychology. But, he came to embody the unsettling features experienced by the profession: people projected onto him their own feelings of conflict (e.g. its claim to be a 'proper' science in the image of the physical ones). Eysenck was the emotional lightning conductor; and, from this source he got the intellectual charge to power him throughout his many scientific and personal 'battles', as he chooses to call them in his autobiography (Eysenck, 1990).

Scientific attitude and canons

Well, what are we to make of Eysenck's attitudes and beliefs? And, importantly, what can we learn that is of relevance to psychology 100 years after his birth? Is he merely a ghostly figure of the scientific past, or does his spirit live on and have relevance for the concerns, both in terms of theoretical perspectives and policy, today?

Eysenck was certain that people differ in their temperament, personality and cognitive abilities, and these individual differences matter for the whole of psychology and its applications (e.g. occupational, educational, and social policy). For this reason, systematic individual differences should be incorporated into all experimental designs, behavioural, psychophysical (and physiological) and neuroimaging studies, as well as all areas of applied research. Burying most of the between-people variance in the 'error' term is not good enough for psychological science that has the serious aim of explanation and prediction.

Running through the entire corpus of Eysenck's work is the view that the mind is a product of nature (biology) and nurture (environment), and it is the two working together that produces the observed phenotype (e.g. extraversion, intelligence and social attitudes). This implies that all psychological research should be biosocial in nature, especially as 'environmental' influences have to go through the brain where significant individual differences are evident in the selection, shaping and interpretation of what is 'out there' (Frith, 2007). In all of this, Eysenck called for the unification of the differential and experimental schools of psychology, seeing them as merely flip sides of the same scientific coin (Cronbach, 1957).

Eysenck also called attention to the nonconscious-automatic nature of behaviour, regulated by conditioning processes (e.g. in those prone to criminality: Eysenck, 1964/2014).

Today many of his views on the nature of mind–brain find a ready audience in judgement and decision making research, and especially in behavioural economics, where System 1 (reflexive-automatic) processes are assumed to reign supreme over System 2 (reflective-controlled) processes (Kahneman, 2012).

Finally, Eysenck may be seen as the grandfather of impact, and not because he chose to follow the expedient path. In the era of Research Excellence Framework (REF)-defined 'impact', Eysenck's call that psychological research should underpin social policy debate seems prescient. However, less consistent with REF impact is his demand that such research should be conducted without consideration of possible outcomes, as these are unknown: scientific knowledge should not be hindered by political concerns of how it might be used. For him, scientific knowledge and political implications are different things and should be keep separate (personal values link the two).

In relation to this point is Eysenck's belief that scientists should be free to search for the truth wherever they think it may be found, and without political (however, small or benign the 'p') influence. In addition, the search for 'the truth' should not be inhibited by fear of offending some people. More contentiously, he argues, scientists should be given intellectual freedom of research and expression, and these should be upheld especially in controversial areas where this rule is best tested.

Many readers will dispute some or all of Eysenck's views; and this is the point. His work raises important issues about how we go about the professional business of psychology and the role of psychology in wider society: they open legitimate debate. But, where do we draw lines in these debates (e.g. in offending other people's cherished beliefs?). Eysenck always pointed to the political winds that blow around the social sciences, which makes it uncomfortable for those wanting to challenge the status quo.

Although he was most certainly an enfant terrible, maybe psychology always needs an Eysenck?

Meet the author

'During my pre-degree study of psychology, I was impressed by the quality, scope and implications of Hans Eysenck's writings. His books are so accessible, are "about people", and they seem to offer scientifically grand theories of everyday behaviour (e.g. smoking and neurosis) – like no other psychologist then or since, Eysenck opened up the promise of a truly integrated scientific psychology. Much later, during my PhD at the Institute of Psychiatry, although this naive impression was moderated by the scientific literature, my appreciation of what Eysenck was trying to achieve never faded. Whilst at the IoP, I met Eysenck and even shared a desk with him for three months, although our paths rarely crossed – my doctoral research contrasted his theory of personality with that of Jeffrey Gray. I could not have imagined that some 20 years later I would be publishing a biography of Eysenck! Despite reservations regarding his specific theories, and especially some of his pronouncements – some of which were plain silly – then and now, Eysenck is a vital life force who set the scientific agenda for us either to work towards or actively oppose. His work, and he himself, still matter.'

- Philip J. Corr is Professor of Psychology at City University London

[email protected]

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