At Our Wits' End, page 10
It would seem that the simplest interpretation of these data, taken together, is that society was becoming gradually more intelligent. This is exactly what would be predicted by the reproductive patterns highlighted in the last chapter whereby those who are likely to have been more intelligent on average—the wealthier half of the population—are enjoying significantly higher fertility than the poorer half.
Genetic Changes:Comparing the Bronze Age to the Present
Ultimately, the frequencies of genetic variants that predict educational attainment and g should have increased throughout historical time, if g really did increase. This is precisely what was found in a 2017 paper in which the frequencies of three different polygenic scores (which the researchers termed POLYCOG)—these being composites of several different genetic variants which collectively predict a portion of the variance in the phenotype of interest—were estimated using a sample of (mostly) Bronze Age Eurasian genomes (from 4.56 to 1.21 thousand years before present). These were then compared with an ancestrally matched European sample of genomes from the 1000 Genomes dataset. It was found that the contemporary sample had significantly higher levels of POLYCOG (using all three polygenic scores). Furthermore, by simply correlating the POLYCOG levels with sample age for a subset of the ancient genomes, a statistically significant positive correlation was found, indicating an increase in these genetic variants over 3.35 thousand years. This can be seen in Figure 5. When we talk about a correlation being ‘statistically significant’ this means that, based on the sample size and strength of the correlation, there is at least a 95% probability that the correlation is not down to chance and it is, therefore, a genuine relationship. In science, 95% certainty is set as the line that must be crossed for something to be accepted as having a high probability of being valid.
Genetic data are not the only ‘solid’ data indicating that g was rising (up until the 19th century). There are also indications that scientific and mathematical geniuses—individuals of great eminence—were increasing in frequency in Western societies until the 19th century. However, to properly understand the factors that go into making genius, it is necessary to get a handle on the nature of personality.
Figure 5. Plot showing the increase in POLYCOG over 3.35 thousand years, fitted to a linear trend.[21]
1 Clark, G. (2007) A Farwell to Alms: A Brief Economic History of the World, Princeton, NJ: Princeton University Press.
2 Viv Nicholson, pools winner—obituary, Daily Telegraph, (12 April 2015), [Online] http://www.telegraph.co.uk/news/obituaries/celebrity-obituaries/ 11531195/Viv-Nicholson-pools-winner-obituary.html.
3 Clark, G. (2007) A Farwell to Alms: A Brief Economic History of the World, Princeton, NJ: Princeton University Press, p. 169.
4 Clark, G. (2007) A Farwell to Alms: A Brief Economic History of the World, Princeton, NJ: Princeton University Press, p. 179.
5 Dutton, E. (2015) The Ruler of Cheshire: Sir Piers Dutton, Tudor Gangland and the Violent Politics of the Palatine, Northwich: Leonie Press, Ch. 1.
6 Moffatt, A. (2011) The Borders: A History of the Borders from Earliest Times, Edinburgh: Birlinn.
7 See: Mortimer, I. (2013) The Time Traveller’s Guide to Elizabethan England, London: Vintage Books, Ch. 12.
8 Pietschnig, J., Penke, L., Wicherts, J.M., Zeller, M. & Voracek, M. (2015) Meta-analysis of associations between human brain volume and intelligence differences: How strong are they and what do they mean? Neuroscience & Biobehavioral Reviews, 57, pp. 411–432.
9 Rock, W.P., Sabieha, A.M. & Evans., R.I.W. (2006) A cephalometric comparison of skulls from the fourteenth, sixteenth and twentieth centuries, British Dental Journal, 200, pp. 33–37. It should be noted that the research team had originally thought that the skeletons were from the mid-14th century. It was later realised that they were from the 13th century. See: Steen, R.G. (2009) Human Intelligence and Medical Illness: Assessing the Flynn Effect, New York: Springer.
10 For an examination of the murders of, and attempts on the lives of, British monarchs, see: Lewis, B. (2011) Dark History of the Kings and Queens of England, London: Amber Books.
11 On the growth of democracy in Britain see: Machin, G.I.T. (2001) The Rise of Democracy in Britain, 1830–1918, London: Palgrave Macmillan.
12 See: Harling, P. (1996) The Waning of the ‘Old Corruption’: The Politics of Economical Reform in Britain, 1779–1846, Oxford: Clarendon Press; or Rubenstein, W.D. (1983) The end of the ‘Old Corruption’ in Britain, 1780–1860, Past & Present, 101, pp. 55–86.
13 See: Owen Lloyd, T. (1973) The Growth of Parliamentary Democracy in Britain, London: Rigby.
14 Hasluck, E.L. (2010) Local Government in England, Cambridge: Cambridge University Press, p. 175.
15 See: Eisner, M. (2003) Long term historical trends in violent crime, Crime & Justice, 1, pp. 83–142.
16 See: Clark, G. (2007) A Farewell to Alms, Princeton, NJ: Princeton University Press.
17 The World Bank (2016) Intentional Homicides per 100,000 People, [Online], http://data.worldbank.org/indicator/VC.IHR.PSRC.P5.
18 Adapted from Eisner, M. (2003) Long-term historical trends in violent crime, Crime and Justice, 30, pp. 83–142.
19 For a history of duelling in England, see: Peltonen, M. (2003) The Duel in Early Modern England: Civility, Politeness and Honour, Cambridge: Cambridge University Press.
20 See: Eisner, M. (2003) Long term historical trends in violent crime, Crime & Justice, 1, pp. 83–142.
21 Adapted from Woodley of Menie, M.A., Yonuskunju, S., Balan, B. & Piffer, D. (2017) Holocene selection for variants associated with general cognitive ability: Comparing ancient and modern genomes, Twins Research and Human Genetics, 20, pp. 271–280.
Five
What is Personality?
As we will see in Chapter Six, a genius seems to combine extremely high IQ with a certain kind of personality. So, to really understand the nature of genius, we need to take a short detour in order to understand what personality is, what different kinds of personality there are, and the huge influence your personality has on everything from your health to what subjects you’re good at in school.
If we return to the computer analogy, intelligence loosely corresponds to the processing efficiency of the computer, while personality reflects the types of software installed on it.[1] A further difference is that, as we have seen, intelligence is measured by IQ tests. Personality is more subjectively evaluated. It is either self-rated using scales upon which you position yourself, or rated by other people (peer-rated). A person high in intelligence, or high on a personality trait such as Conscientiousness, is ‘high’ in relation to other people and, as with intelligence, personality changes with age.[2]
The Big Five
Differences in personality predict differences in how people will respond in different situations. How near to you does a car moving at high speed have to be before you decide that it is too risky to cross the road in front of it? How many irritating things have to happen to you in a day before you lose it and start yelling? How strongly does how others feel influence how you feel?
Different people will answer these questions differently and they’ll do so because they have different kinds of personalities. On a personality test, people are asked whether a certain behaviour, or like or dislike, is present or absent in them; or else asked to rate its strength on a scale. For example, the Newcastle Personality Assessor includes the following statements about yourself: ‘Starting a conversation with a stranger’, ‘Insulting people’, and ‘Feeling stressed or worried’. With each statement you have to rate the extent to which they apply to you on a scale ranging between ‘Very unlike me’ and ‘Very like me’.[3] These kinds of questions can be analysed and averaged to yield a few personality ‘traits’ which cluster together.
While many models of the structure of personality have been proposed over the decades, the model with the greatest currency in modern personality psychology holds that personality can best be understood in terms of five essential personality characteristics: these are the ‘Big Five’,[4] with each corresponding to a dimension between positive and negative extremes separated by a dash:
(1) Extraversion–Introversion. Extraversion is feeling positive feelings strongly. It is associated with being outgoing and gregarious (i.e. enjoying the company of others). Introversion is experiencing these feelings weakly, and is associated with being self-reliant.
(2) Emotional Stability–Neuroticism. Neuroticism is feeling negative emotions strongly. A person high in Neuroticism is emotionally unstable and prone to mood-swings, anxiety, and depression.
(3) Conscientiousness–Impulsiveness. Conscientiousness refers to impulse control. People who are high in this are self-disciplined, hard-working, and rule abiding.
(4) Agreeableness–Disagreeableness. Agreeableness refers to those who are high in empathy and who are pro-social. They deeply care about, and empathise with, how others feel.
(5) Openness-Intellect–Closedness-Instrumentalism. Openness-Intellect is a broad domain of personality, which references intellectual curiosity and a preference for novelty, progressive politics, creativity, aesthetics, and unusual psychological experiences. The opposite pole of this domain is characterised by lack of interest in novelty, a preference for conservative politics, and pragmatism. Openness-Intellect weakly, but significantly, correlates with intelligence, at 0.3. This is because it—or the ‘Intellect’ domain anyway—is measuring some of the same things.
These five personality traits are (except for Openness-Intellect) regarded as independent of IQ scores and our placing on them predicts how we behave. For example, high Conscientiousness as a child predicts greater success in the education system and in the world of work. High Neuroticism is associated with mood swings, anxiety, and depression. Indeed, it is correlated with suffering from depression at 0.8.[5] High Extraversion predicts early death because extraverts are more likely to take risks, because they will enjoy the resulting pay-off so much more. One study found that high Extraversion leads to a three-fold increase in the risk of early death.[6] Extraversion also predicts poor health, because of the extra enjoyment that will be found in food or smoking. Unsurprisingly, high Agreeableness predicts having lots of friends while low Agreeableness is associated with marital breakdown and criminality.[7]
The General Factor of Personality
The Big Five were developed from the Big Three traits defined by psychologist Hans Eysenck (1916–1997). Eysenck arrived in England from Germany in the 1930s and made his temporary visit permanent after the Nazis, whom he loathed, came to power. Eysenck became the dominant personality in British academic psychology.[8] The Big Three are Extraversion, Neuroticism, and Psychoticism. In effect, the Big Five dimensions of Conscientiousness and Agreeableness are the opposites of various aspects of Eysenck’s Psychoticism; and Openness-Intellect takes some aspects of Psychoticism and blends them with behaviours characteristic of modern intellectuals or artistic types.
Like Eysenck, British-born Canadian psychologist J. Philippe Rushton (1943–2012) was a highly original thinker; to the extent that he was prepared to tackle controversial ideas. When he was a PhD student in London, Rushton attempted to protect Eysenck from a student mob protesting what they perceived to be ‘controversial’ aspects of his work, and got punched for his troubles. Rushton showed that the Big Five (and Big Three) are all co-correlated, and could all therefore be reduced to a single personality variable, which he called the General Factor of Personality (GFP). The GFP can be understood as the single foundational dimension of personality, corresponding broadly to social effectiveness—or the ability to effectively read people and social situations and to behaviourally regulate oneself. This underlies the more specific personality traits—akin to how general intelligence or g underlies all the specific cognitive abilities, as we have already explored. With personality, you have the ‘aspects’ or ‘facets’—lots of very specific traits such as ‘courage’ or ‘jealousy’. These can be reduced down to the Big Five and these, in turn, yield a Big Two comprised of a broad Stability factor (encompassing Conscientiousness, Agreeableness, and Emotional Stability) and a Plasticity factor (comprising Extraversion and Openness-Intellect). The Big Two always correlate. This gives rise to the g factor of personality; the ‘General Factor of Personality’.[9]
So the General Factor of Personality (GFP) can be conceptualised as the degree to which a personality is socially desirable and socially effective. GFP describes a basic personality dimension, high levels of which (it is suggested) evolved as an adaptation in complex and stable societies so that people would ‘get along together’. So a person with high GFP would be socially extraverted, be empathic and concerned with the feelings of others, conscientious and self-disciplined in pursuit of socially-approved goals, have stable emotions, and be open to new ideas. The existence of the GFP is also why people say things like ‘She has a nice personality’, or ‘He’s shallow!’: the idea being that people intuitively understand that there is one ‘core’ personality trait with socially desirable and undesirable poles—and that paying attention to this in choosing mates and allies likely would have had significant evolutionary pay-offs. Unsurprisingly, the GFP predicts likeability and employability, and is substantially correlated with (and is essentially the same thing as) Emotional Intelligence.[10] This is the ability to ‘know’ yourself and take command over your emotions, which, as was discussed earlier, is sometimes touted as a sort of ‘second’ intelligence, but is really a mixture of general intelligence and the GFP, with such traits properly belonging in the ‘personality realm’.
How Personality Develops and Why there are Differences
Personality develops throughout the lifespan.[11] Anyone who has ever had a four-year-old child will notice that, in comparison to a child of ten, the four-year-old will have lower impulse control and is more likely to have a tantrum, is less considerate to his or her friends, and is far more likely to become scared of something or inconsolably upset. We equally see that the elderly tend towards being non-aggressive and highly resistant to change; ‘set in their ways’. In the 18th-century satire Gulliver’s Travels, Gulliver travels to the land of Luggnagg where he meets a people called the Struldbruggs. They are immortal but lack the gift of eternal youth. In consequence, the very elderly do not even speak the same language as the young. The language has been evolving, but they are too set in their ways to keep up with this. This fits with what we know about the development of personality over the lifespan.
We don’t know much about how the GFP changes, so let’s stick to the well-studied Big Five for the time being. Conscientiousness increases with age up until puberty, where people regress a bit, and then from early adulthood it continues increasing. Exactly the same is true of Agreeableness. In males, Neuroticism simply decreases with age, while in females it decreases with age until adolescence, when it increases, before beginning to decline in early adulthood. For this reason, though there is much variation within the sexes, women score higher in Neuroticism then men and are more prone to anxiety.
It is interesting that the move towards higher Conscientiousness as one gets older experiences a blip during adolescence. It may be that there is some evolutionary benefit to this, such as young people being less inhibited and therefore potentially more creative, and so being more likely to attract the attention of a mate or produce some useful innovation for society at large. Such behaviour patterns might also make them more likely to break or loosen the bond with their parents, incentivising them to make their own mark on the world—the famed psychoanalyst Carl Gustav Jung (1875–1961) called this process Individuation.[12] Once people reach adulthood their personalities, compared to others of their own age, are fairly stable. For example, one study found that the correlation between personality scores over six years on the same adult sample was 0.85.[13]
There are clear personality differences between males and females. These fit with stereotypes about women entering caring professions and men being more aggressive and inclined to fight and compete. By the time they reach adulthood, women are higher in Agreeableness and Conscientiousness than men: they have higher impulse control and they are kinder. This would make women better carers for children and men higher in competitive drive and aggression. This should be borne in mind when people bemoan the fact that high-stakes, money-oriented professions like finance or even politics are male-dominated, but nursing and school teaching are female-dominated, as these differences are precisely what male–female differences in personality would predict. Women are also higher in Neuroticism than men, as already noted, which would mean a greater proneness to suffering from stress. They are higher in some Extraversion facets than men, more likely to be outgoing, for example. The differences on Openness-Intellect are at the facet level. Women are higher in ‘Aestheticism’; men are higher in ‘Intellect’.[14] So, you would predict that women would be more interested in the arts and men more interested in the sciences.[15]
