Richard Lynn, Race Differences in Psychopathic Personality: An Evolutionary Analysis, Augusta, GA: Washington Summit Publishers (In Press), Pp 368., US $ 29.95., reviewed by Evelyn Quinn
Professor Richard Lynn, the doyen of differential psychology, is well known for his work on national and racial differences in intelligence. In his latest book, he breaks new ground, proposing that there are also race differences in psychopathic personality. He was inspired here by Richard Herrnstein and Charles Murray’s The Bell Curve (1994). It showed that in the United States, blacks have the lowest intelligence and whites the highest, while Hispanics are intermediate. These intelligence differences supposedly explain why a number of social pathologies, notably crime, poverty, welfare dependency and single motherhood, are unevenly distributed across divergent populations.
Concerning black-white difference in crime rates, Herrnstein and Murray state that when IQ is taken into account, “…we are still left with a non-trivial black-white difference”. For instance, with crime rates set at 1.0 for whites, blacks had a rate of 6.5. When blacks and whites were matched for intelligence, the rates were reduced to a black-white ratio of 5:1. Thus, blacks with the same IQ as whites still had a higher crime rate. Herrnstein and Murray conclude that some other factor must account for part of these race differences in crime. Lynn argues that this other factor is racial differences in psychopathic personality.
In presenting this case, Lynn treats psychopathic personality as a continuously distributed personality trait. He calculates the race differences from studies of self-assessment with personality questionnaires and from rates of crime, conduct disorder in children, cheating in sport, sexual promiscuity, pathological gambling, inability to delay gratification, drug abuse and child neglect – all behavioural expressions of psychopathic personality. Studies are also summarised for race differences in pro-social personality treated as the antithesis of the selfishness and lack of social concern of the psychopathic personality and assessed by organ donation and charitable giving.
Lynn contends that psychopathic personality is strongest in Australian Aborigines, followed successively by sub-Saharan Africans and Native Americans, New Zealand Maori, Hispanics and South Asians, and is weaker in Europeans and weakest in North East Asians. These race differences are the reverse of those in intelligence that Lynn reports in his Race Differences in Intelligence. He proposes that they both evolved as adaptations to the climatic environments to which the races were exposed. The North East Asians experienced the coldest winters and springs and the Europeans experienced the next coldest, and that these exerted selection pressures both for higher intelligence and for weaker psychopathic personality.
The author identifies three selection pressures against psychopathic personality and for the enhancement of pro-social personality in North East Asians and Europeans; to wit, pressures for the evolution of stronger male-female pair bonding; for an increased capacity to delay gratification; and for a greater need to maintain harmonious and co-operative social relations.
Stronger male-female bonding based on love evolved as a result of the need for both parents to provide care for their children. This would have been strongest for North East Asians because they experienced the greatest need for co-operation between parents for provisioning children in the cold winters and springs during which plant and insect foods were not available and women and children needed men to provide them with meat foods that they had to obtain through hunting. The men in question required long term commitment from their female mates and children to provision them and more responsible and concerned parenting, and they did this because they were strongly pair bonded with their women partners. This requirement was a little weaker in Europeans, and considerably weaker in the races that inhabited the less severe environments of the Americas, South Asia and the Pacific Islands, and was weakest in Australia and sub-Saharan Africa in whose benign climates women could feed their children throughout the year by gathering plant and insect foods with little or no help from men, and for whom male-female bonding based on love was therefore the least important.
Concerning the aforementioned increase in the capacity to delay present gratification, many foods in Eurasia were only available at certain times of the year and these had to be stored for future consumption. For example, salmon are plentiful when they return from the sea and run up rivers and many of them can be caught. They can then be stored in ice boxes or smoked and kept for months. Collecting and storing these for future consumption would have required foresight and the ability to delay present gratification.
The third selection pressure of cold winters and springs was for an enhancement of pro-social personality as men became increasingly reliant on group hunting. For this they needed to develop a greater capacity for co-operation, the maintenance of harmonious social relations and stronger control over aggression towards other group members. Lynn surmises that the reduction of testosterone, the male sex hormone responsible for aggressive behaviour, was the principal neuro-physiological adaptation by which these components of psychopathic personality were reduced in the Europeans and North East Asians. He cites evidence for race differences in testosterone measured directly and indirectly through racial differences in the dimensions of male genitalia.
Lynn makes a powerful case that differences in psychopathic-pro-social personality are as important as those in intelligence in explaining racial differences in a wide range of social and economic phenomena, both within and across nations. Here, arguably, is the missing link posited by Richard Herrnstein and Charles Murray in The Bell Curve.
Editorial note; According to Jordan Peterson, Professor of Psychology at the University of Toronto, psychometrics has been subjected to such relentless scrutiny that it is now the most robust component of contemporary psychology.
Evelyn Quinn has a Ph.D. in Psychology from University College, Dublin