What is Personality, What is
Intelligence?
Intelligence and Personality are the
two main ways that psychologists have developed for describing differences
between people.
In brief – Intelligence is an ability,
while personality is character; intelligence is general – with the level of
intelligence affecting many specific abilities, while personality can be
understood as a pattern of motivations, preferences, satisfactions.
In terms of computers – intelligence
is something like the processing speed, while personality is about the types of
software installed. Or, intelligence is about the efficiency of the brain,
while personality is about what that brain is designed to do. Or intelligence is about how well the brain
works; while personality describes the circuitry, the hard-wiring – what kind of brain it is.
A further difference is that
intelligence is measured by tests – IQ tests; while personality is evaluated by
human beings – either self-rated using self-describing scales, or else rated by
other people.
But a similarity is that both IQ and
personality are (nearly always) comparative measurements. A person ‘high’ in intelligence, or high on a personality trait such as
Conscientiousness, is high’ relative to
other people. ‘High’ or ‘Low’, in both intelligence and personality,
therefore does not describe an
objective measurement of a personal attribute in the way that (for example)
high or low blood pressure or blood sugar measurements would.
Personality
Personality is, in essence, our
general way of being. Subtle differences in personality predict differences in
how people will respond in a certain situation.
Personality evaluations are usually
measured by questionnaires: How close does a car moving at a certain speed have
to be to you before you judge that it is too dangerous to cross the road in
front of it? How many annoying things have to happen to you in a day before
your lose your temper and raise your voice? How strongly do the emotions of
others impact how you feel?
Different people will give different
answers to these questions, in part because of variation in their personality. Typically
people are asked whether a certain behaviour, or like or dislike, is present or
absent in them; or else asked to rate its strength. Multiple such questions can
be analysed and averaged to yield a few personality ‘traits’ which cluster
together.
The exact number of these traits used
by psychologists depends on the purpose of the personality evaluation. The
number can be as few as one general master trait (e.g. pro-social versus
anti-social – see below), or dozens of specific traits such as aggression, or
courage – but usually, for convenience, the number of traits used for
describing personality have been something between about two and five.
Although we will be suggesting
revisions and improvements to the scheme, many psychologists currently suggest
that personality can best be understood in terms of five essential personality
characteristics: these are the 'Big 5’, which each make a scale between
extremes separated by a dash:
(1)
Extraversion - Introversion: Experiencing positive feelings strongly.
(2)
Neuroticism - Emotional Stability: Experiencing negative feelings strongly.
(3)
Conscientiousness - Impulsiveness: Impulse control and a need to follow rules.
(4)
Agreeableness/ Empathizing - Indifference to other people: Altruism; empathy
for others.
(5)
Openness-Intellect - Aversion to change/ intellectual conservatism:
Intellectual curiosity, creativity, hypnotisability, unusual psychological
experiences. This weakly correlates with intelligence, as it is measuring some
of the same things.
These are (except for Openness-Intellect)
independent of IQ scores (at least within normal IQ ranges); and our placing on
them predicts how we behave. For example, high Conscientiousness as a child
predicts greater education and employment success; high Neuroticism predicts
problems with mood swings, anxiety and depression. High Openness-Intellect will
result in being an impractical, though perhaps artistic or spiritual, dreamer.
A moderately high score, however, is a predictor of artistic success – or at
least, on some measures of artistic success that focus on the production of
novelty (although, we will argue, not to genius).[1]
The Big Five were developed from the
Big Three traits defined by psychologist Hans J. Eysenck (1916-1997), who
arrived in Britain as a refugee from Nazi Germany. These are Extraversion,
Neuroticism and Psychoticism.[2] In
effect, the Big Five dimensions of Conscientiousness and Agreeableness are the
opposites of various aspects of Eysenck’s Psychoticism; and Openness takes some
aspects of Psychoticism and blends them with behaviours characteristic of
modern intellectuals (as may be inferred from this description, we regard
Openness as a concept of dubious biological validity).
Like Eysenck, the British-born
Canadian psychologist J. Philippe Rushton (1943-2012) was an original thinker,
unafraid to tackle controversial ideas.[3] Rushton showed
that the Big Five (and Big Three) are all co-correlated, and could all therefore
be collapsed into a single personality variable, which he called General Factor
Personality (GFP).[4]
GFP can be conceptualized as the single dimension of personality – from
pro-social to a-social - which underlies the more specific personality traits –
analogously to how general intelligence or ‘g’ underlies all the specific
cognitive abilities, something which we explore below
So General Factor Personality can be
conceptualized as the degree to which a personality is prosocial personality – in other words, the degree to which someone
has the kind of personality type and behaviours that underpin many socially
desirable traits, the degree to which someone approximates to the type of
person that makes for friendliness, helpfulness, being a ‘good neighbour’; for
peaceful, orderly, cooperative, hard-working, placid citizens.
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 sociably 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.
Marvellous as the high GFP person
sounds, throughout this book we argue that a personality of almost the opposite
type is necessary for the true genius (not the only thing required, but
necessary) – we call this the Endogenous personality, and this new concept will
soon be described in detail.
But in summary, the Endogenous
personality, necessary for genius, is self-sufficient, indifferent to the
opinions of others or normal social aims, being instead wrapped-up in his own
personal goals, and making judgements using his own internal, subjective
evaluation systems – he will work very hard and for long periods on his own
projects, but will not willingly go-along with other people’s plans and
schemes. But more on this later…
Personality traits, depending on how
they are measured, have been shown to be in the region of 50% to around 70%
heritable, based on twin studies.[5] (Heritability
is a measure of how closely parents resemble their children in a group study –
the number refers to how closely the parents personalities predict the child’s –
heritability of one would mean that children’s personalities were wholly a
product of their parents’ personalities; zero would mean the mathematical
relationship between parent and offspring’s personalities was random.)
Since the heritability of personality is
less than one, some combination of chance and the environment does affect the
kind of personality which you develop, but only within certain genetic limits.
An unstable, dangerous childhood will tend to increase mental instability, and
those who experience it will learn to see the world as a dangerous place – and
this may have a lasting effect on their behaviour (this calibration of adult
behaviour to childhood environment is the subject of Life History studies in
biology – humans as well as animals).[6]
For instance, when childhood is
unpredictable and dangerous, children will tend to be calibrated to ‘live for
the now,’ so displaying lower Conscientiousness, and they may be suspicious of
other people, leading to lower Agreeableness.
Another example is that girls who have
grown up in sexually-unstable situations seem to adopt a short-termist sexual
strategy, having children with a variety of men who are chosen for their
dominance (hence probably good genes) rather than their ability to remain
committed to a relationship and provide resources over the long term. In slang
terms, girls from unstable homes may exhibit a preference for ‘cads’ rather
than ‘Dads’.[7]
Intelligence
So much for personality, what then is
intelligence?
'Intelligence' can be seen as the
ability to think abstractly and to learn quickly – this leads to an ability to
solve problems quickly, but only when those problems have previously been
encountered. In problem solving, intelligence provides fast processing and a
larger knowledge base, but intelligence is not
about being original or creative.
Intelligence is measured by IQ tests (meaning
Intelligence Quotient; see below) and IQ test scores in childhood will predict
many important things – higher intelligence predicts higher education level,
higher socio-economic status, higher salary, better health, greater civic
participation,[8] lower
impulsivity, and longer lifespan[9]; lower
intelligence predicts higher criminality, and (probably causally related to
crime) shorter-term future-orientation.[10]
So, mostly high intelligence predicts
desirable outcomes – however there is one important exception: high
intelligence, in modern societies, predicts lower fertility, especially among
women. Thus, in modern societies (with access to birth control) the most
intelligent women average less than one child, because so many intelligent
women have zero children, and very few have large families.[11] Some
people argue to a broader definition of intelligence, including ‘emotional
intelligence’ for example. But there is, in general, no need to separate this
from ‘intelligence’ as we define it. The ability to solve social problems has
been shown to be predicted by intelligence.[12]
Intelligence is measured by IQ tests.
These typically measure three forms of intelligence: verbal, numerical (mathematical)
and spatial (geometric). Some individual people are higher in one form of
intelligence than another, and rarely there may be above average measures in
one measure of intelligence and below average in another - but, overall, in
group studies all of the many different measures of cognitive ability
(vocabulary, general knowledge, reading ability, puzzle solving, algebra,
what-comes-next sequences of numbers or of symbols etc.) will always positively
correlate. It is consistently found that, within-groups and between-groups,
high ability in one task goes with high ability in other tasks, and vice versa.
This is why intelligence is called ‘general’,
and why it can be compared with processing speed in a computer – a ‘faster’
processing computer is better at doing almost every kind of task – all the types of software (graphics,
statistics, word processing etc.) will run more efficiently. And not only does
a fast computer complete tasks more quickly, but a fast computer can also do
things that are – in practice - impossible for a slower computer (which will be
unable to cope with the load and sequence of computations, and will ‘seize-up’.).
The positive correlation between
cognitive measures means that we can talk about a ‘general factor’ that
underpins all of them. The IQ is a statistical construct which measures an
inferred ability which underlies all of these cognitive abilities. This underlying
ability is known as ‘g’ for ‘general intelligence.’
Intelligence increases throughout
childhood and decreases in old age (probably from early adulthood, but slowly) and,
as such, IQ is usually a comparative measure – comparing the individual with a group
sample of the same age. The IQ number is a way of expressing the individual’s
position in a rank ordering of IQ test scores for his age group; hence the term
‘intelligence quotient’ (IQ) (the average IQ is called 100, often calibrated
against the UK population average), larger numbers are above average
intelligence (expressing this is percentage terms) and lower numbers are below
average. A person’s intellectual ability must be compared to a reference group
of their own age because intelligence increases throughout childhood and
adolescence and decreases from middle-age onwards.
It is very important to recognise that
IQ is therefore a comparative measure – and this limits its usefulness –
because intelligence in a person or group is being measured only relative to another person or group.
The results of IQ tests strongly
correlate with intuitive measures of thinking ability (such as school work) and
they are not merely culturally influenced (although, naturally, culture and
familiarity do have some influence). We know that IQ testing is valid and
robust across cultures, because the cultures (or sub-cultures) that do badly in
IQ tests do the least-badly on the most culturally-biased parts of the test,
and also because the IQ test results correlate with something objective -
differences in simple reaction times - and reaction time correlates with IQ.[13]
As already noted, intelligence is a
vital predictor of life outcomes. Approximately 70% of the variance in school
performance is explained by differences in intelligence, 50% of the variance
among university undergraduate performance and 40% of the variance in
postgraduate performance. Intelligence explains about 30% of the variance in
salary and is a clear predictor of job status.[14]
It has been found that less-selective professionals,
like teachers and nurses, have an IQ of about 110, while it is 120 for doctors
and lawyers, and even higher for those who rise to the top of these
professions.[15]
Within academia, the average PhD student in education has an IQ of around 117,
while the average PhD student in Physics has an IQ of 130.[16].
As with personality, intelligence is
strongly heritable – indeed the heritability measures are higher for
intelligence than personality, perhaps because the IQ is a more precise and
valid measure than are personality ratings. Around 80% of the variance in
intelligence is probably genetic – overwhelmingly, therefore, intelligence is
inherited from parents.[17]
Environmental factors include
sufficient nutrition and a sufficiently intellectually stimulating environment
when growing up. Just as important is an intellectually stimulating adult
environment, which those with high intelligence will tend to create for
themselves. For this reason, among others, the genetic component of IQ during
childhood is relatively low, as the child’s environment will reflect its
parents’ intelligence. Only as the child reaches adulthood will its environment
reflect its own intelligence, leading to a genetic component of 80%.[18]
High intelligence is a sign of having
an overall-efficient, fast-processing brain - requiring (as American
psychologist Geoffrey Miller has pointed-out) ‘good genes’; which mostly means a
minimal load of deleterious mutations.[19]
Deleterious genetic mutations occur spontaneously
in every generation – due to any cause of mutation (radiation, chemical, heat
etc.) or from DNA copying errors – and some non-lethal but potentially-damaging
mutated genes are usually inherited from parents. Nearly all chance gene
mutations are harmful – and only very rarely are they ‘adaptive’ and improving
of function (but it is these very rare beneficial mutations that are the basis
of evolution by natural selection).[20]
In general, however, spontaneous
mutations reduce ‘fitness’ (i.e. reduce reproductive potential) and the human
species has needed to prevent mutations from accumulating every generation as
inherited mutations are added-to by new mutations. Somehow, these mutations
need to be continually removed from the human population, or else they would
overwhelm and destroy the species in a process termed Mutational Meltdown.
Therefore
science requires understanding ,and understanding is qualitative not
quantitative - understanding is not about
description and measurement.
(These
are possible when scientific understanding is utterly lacking; - they can even
be done mechanically even, by a machine - although there must first be
some-thing to draw-a-line-around that which is described or measured.)
The difference between intelligence and IQ
The
difference is that intelligence is the real, underlying psychological function,
whereas IQ is a score achieved in a test – a score which is intended to compare
and measure intelligence but which is an indirect, only partly-precise and only
partly-valid measure of intelligence.
Therefore,
we can think of a qualitative, subjective understanding of the phenomenon of real
intelligence as an irreducible
entity - not understood in
terms of other things nor only in terms of what it does, but in terms of itself as a
real thing which we can detect and measure only indirectly. And we can then
conceptualize IQ as the practical, simplified, publicly-shareable way of
conceptualizing and investigating intelligence.
IQ can be, and usually is, researched in a 'theory-free' fashion, with operational definitions based on proxy description, measurement by comparison, and correlation – indeed intelligence sometimes asserted to be nothing-more than a mathematically-derivation from IQ scores.
But we
would emphasize that to understand intelligence requires understanding that a
person may be of high intelligence and not have a similarly high IQ score - and that this may be the case no matter how
validly, how often and how carefully the IQ is measured and calculated. And
another person may have high IQ scores (measured in the best ways and by the
best methods) yet not be of similarly high
intelligence.
This is a
simple consequence of the fact that intelligence is not reducible to IQ score or any
other measurement: it is an indivisible, qualitative entity.
Intelligence can be 'thought' hence understood -
but understanding intelligence is like knowing a person (as compared with
describing a person, their hair colour, height etc); getting to know
intelligence is therefore like getting to know a person - it is a result of
experience.
For
instance, highly intelligent people who do not score highly on IQ tests are easy
to understand - because anything which reduces test performance could lead to
this outcome: illness, pain, impaired consciousness and concentration from
sleepiness, drugs, drug-withdrawal, mental illness... there are multiple
causes, and some are chronic (long-lasting, perhaps life-long).
And people with high IQ scores who are not of similarly high intelligence are familiar to anyone who has attended a highly-selective college or educational programme or who are members of intellectually 'elite' professions; since they make-up the majority of participants. The 'Flynn effect' - of rising average IQ scores over the twentieth century in a context of reducing average real-intelligence – can indeed be understood as an historical record of the emergence of more and more people with high IQ scores who do not have similarly high real intelligence.
After (probably)
six or eight generations of rising average IQ scores and falling real-general
intelligence; the gap between
intelligence measured in terms of IQ scores and intelligence understood as a
real underlying phenomenon is by now very large. Indeed, it seems likely that
many or most people among modern high IQ scorers do not have similarly high real-intelligence. This would be expected
to apply especially at highly-educationally-selective institutions
where Endogenous personalities are substantially selected-out by the
decades-long trend for an increasingly-high minimum-threshold of conscientiousness
imposed by educational qualifications.
The
correlation between IQ score and 'g' was probably much higher in the past
(a century plus ago) than it is now – meaning that the distinction between IQ
score and real, underlying intelligence is more important now than it used to
be.
The evolution of intelligence and the rise of the Endogenous
personality
Geoffrey Miller’s emphasis on intelligence
(he emphasizes particularly ‘creative’ intelligence) providing a ‘fitness
measure’ which one person can evaluate in another; and his noting that relative
IQ provides a quantitative correlate of deleterious mutations - is worth
pausing over and amplifying.
This implies that high IQ serves as a kind-of
guarantee and advertisement of ‘good genes’ – and this is why high intelligence
is regarded as attractive, and therefore why men and women of higher
intelligence tend to pair-up in marriage in much the same way that good-looking
men and women tend to pair-up (this system of like pairing with like is termed assortative
mating).
We have already noted that
intelligence correlates with fast reaction times. This strongly implies that ‘intelligence’
is simply the function of a brain that is working well, just as strength is the
function of muscle that is working well. The human body has evolved to work
optimally well in a particular environment and the same is true of the human
brain. Detailed historical research by British economist Gregory Clark has
shown that until the Industrial Revolution a form of natural selection was
operating in Western societies. Those who were not physically strong, who did
not have strong immune systems, who were of low intelligence and unable to work
steadily for long hours would usually either die as children or be unable to
raise children of their own; and would thus be unable to pass on their
deleterious genes.[21]
In other words, until about 1800 only the
minority of people with the ‘best genes’ (i.e. the lowest mutation load) would
be able to survive and reproduce. Deleterious mutations were fileted-out from
the population every generation by this harsh form of natural selection.
In much the same way, the number of
surviving offspring was predicted by socioeconomic status – and therefore
intelligence – is pre-Industrial Europe. Clarke shows that in seventeenth
century England, for example, the richer 50% of those who left wills had 40%
higher completed fertility (children of their own, still alive when they passed
away) than did the poorer 50%. This makes perfect sense. Those with low levels
of deleterious mutations would, for that reason, have high intelligence and a
high functioning immune system. As such, they would attain or maintain high
socioeconomic status, and, in a context of limited medicine, their offspring
would be more likely survive. In addition, genes for intelligence would permit
them to become wealthier, meaning they could better protect themselves, and
their offspring, from disease, poor living conditions and accidents, and they
could afford to have large numbers of children (ensuring at least some
survived), without risking starvation. These two related processes would ensure
that the children of the richer survived better.
The message seems to be that in
pre-industrial Europe (before about 1800-1850) natural selection on humans
operated mostly via mortality rates – especially child mortality rates. An
average of more than half of children would die before adulthood, but this
consisted of near total mortality rates among the children of the poor, and
ill, and of low intelligence or ‘feckless’ personality; whereas among the
skilled middle classes (clerks, merchants, lawyers, doctors etc.) the mortality
rates were lower and fertility (number of births) was high. Therefore in each
generation most of the children came from the most intelligent group in the
population, and over several generations almost all the population would have
been children of the most intelligent (also conscientious, and relatively
peaceful) sector of the population.
(This is why anyone English who has
ever traced their family tree will find that by the sixteenth century – when
records begin – their ancestors are, at the very least, wealthy though
non-aristocratic farmers (‘yeomen’ or richer ‘husbandmen’).[22] And this
is why every English person alive is descended from King Edward III - 1312-1377!).[23]
Clarke argues that this harsh natural
selection resulted in an increase of average intelligence with every generation,
and ultimately culminated in the intellectual and social breakthroughs of the Industrial
Revolution. It meant that there was a percentage of the society whose
intelligence was so high that the necessary breakthroughs could be made and that
the society as a whole was sufficiently intelligent such that it could maintain
and even develop these breakthroughs. Furthermore, the workforce developed a
personality type which was pre-adapted (by preceding Medieval natural
selection, operating over several hundred years) to the needs of large scale
industry and complex social organization.
This ‘eugenic’ (i.e.
fitness-increasing) situation stopped in the wake of the Industrial Revolution
and soon went into reverse; with socioeconomic status becoming negatively associated with fertility,
especially among women. In other words, after the Industrial Revolution the
direction of natural selection turned upside-down, with higher social status,
wealth and education leading to lower reproductive success.
This process – known as dysgenics (i.e.
selection that is reducing fitness) – has been documented by British
psychologist Richard Lynn. In addition, Lynn notes that the pattern of reproduction
ceased to eliminate genes that would lead to a poor immune system or various
physical impairments. Modern medicine means that genetically-damaged people can
procreate leading to a dysgenic impact on health, more deleterious genes and
thus a further negative impact on intelligence.[24]
Probably the most significant impact
of the Industrial Revolution was in reducing child mortality rates from more
than half to (eventually) just about one percent. For the first time in history,
almost all the population, including the poorest classes and those with the
heaviest mutation loads, were leaving behind more than two surviving children.
Over a few generations, the mutational load must have accumulated – fitness
must have declined – and average intelligence must have reduced due to the
effects of deleterious mutations on brain development and functioning.
Since intelligence is correlated with
genetic quality, this inferred population level mutation accumulation implies
that average intelligence should have declined since the Industrial Revolution.
The inferred decline in general
intelligence due to both mutation accumulation plus ‘dysgenic’ patterns of
fertility, can be measured using simple reaction times, which correlate with ‘g’
– and it has been found that reaction times have slowed considerably since the
late 1800s when reaction times measurements were first performed.
We will return to discuss this matter
further – but so far it seems that intelligence first increased due to natural
selection in the Medieval era; then has declined due to the changes in natural
selection at the time of the Industrial Revolution.
So, what about personality – how was
personality affected by natural selection on the European population, first in
the Medieval era, then through the Industrial Revolution?
In sum, it seems that Medieval Europe
was a breeding ground for high intelligence – which is one component of genius;
but also a breeding ground for pro-social extraverted people of stable ‘high
GFP’ personality type, high in conscientiousness, empathic; obedient, good at
working regular hours and getting along with their neighbours.
However, although high intelligence is
a component of genius, and although an average pro-social personality type is
useful, and perhaps essential, for successful industrial societies; the high
GFP/ pro-social personality is almost the opposite
of that required to make a genius. And yet, late Medieval and Renaissance Europe
was a veritable hotbed of genius, and it was these geniuses who enabled and
triggered the Industrial Revolution!
So, how can the average population
increase in pro-social personality, yet that same population generate
individuals of exceptionally high intelligence who have the ‘asocial’ Endogenous
personality type, some of whom made major breakthroughs and became recognized
as geniuses?
Two ways of being highly intelligent; Good genes or the
Endogenous personality
Most people would probably say that an
Endogenous personality was a matter of sheer chance – that in a population
characterized by high GFP, a few individuals just happened (by random
variation) to have low GFP - and this low GFP/ Endogenous personality group
included some individuals of very high intelligence who were the potential
geniuses.
But our suggestion is different: we
suggest that the high rate of European genius was not an accident. We will
argue that the Medieval European population was under group selection as well as
individual natural selection – and specifically that it was group selection
which led to the evolution of geniuses.
In a nutshell, the Endogenous
personality evolved in a high intelligence population to provide a minority of
geniuses, whose function was creative problem solving and invention
specialists. The activities of this minority of geniuses had disproportionate
impact, and were of general benefit to the survival and /or expansion of the
social group among whom the geniuses lived and worked.
Indeed,
we would argue that there are two ways of being exceptionally intelligent. The
usual way is that someone in a population is exceptionally intelligent is by
what is termed Good Genes: that is, having few faults or errors - the person
has a normal brain but with nothing (or nothing much) wrong with it. In other
words he has a low load of deleterious mutations (or, conversely, he is not suffering from mutation
accumulation).
But there
is another way - which is by having an Endogenous personality - which means
that his brain is purposely designed
(by group selection) to be creative, to make breakthroughs. Such a person is,
in sum, a genius (albeit very probably not a world historical genius; but a
tribal or local genius).
Our
assumption is that in the potential genius – and if we could measure it, which
is not possible at present - we would see a brain wired-up to be intelligent.
Therefore
the brain of an Endogenous personality has high intelligence not so much
negatively from lack of mutations; as positively - because it is a brain
specialized (by evolution) to be highly efficient for the purpose of creative
discovery.
And this
is why the genius has a special (Endogenous) personality. Usually personality
and intelligence are almost distinct and little-correlated; but the brain of a
genius is differently wired from a normal brain: it is a specialized and
purposive brain, a lop-sided brain, a brain in which some circuits usually used
for social intelligence and reproductive success are co-opted to this purpose.
In sum, the brain of a genius is one that is
specialized for creative discovery and both high intelligence and an
'inner-oriented' personality are features of this specialization. This is why
personality and intelligence go together in the genius, whereas in ‘normal
people’ personality and genius can vary almost independently and there is
little correlation between the two.
We have discussed, then, the concepts
of personality and intelligence and the factors that lead to differences in
them. We will now attempt to understand how these relate to Genius.
[1]
For a more detailed introduction to ‘personality’ see Nettle, D. (2007). Personality: What Makes You Who You Are. Oxford:
Oxford University Press or G. Matthews,
I. Deary & M. Whiteman. (2003). Personality
Traits. Cambridge: Cambridge University Press
[2] Eysenck, H. J.
(1993). Creativity and personality: Suggestions for a theory. Psychological
Inquiry, 4, 147-178 or Eysenck, H. J. (1992). The definition and
measurement of psychoticism. Personality
and Individual Differences, 13: 757-785.
[3] See, Nyborg, H.
(2015). Obituary: J. Philippe Rushton: Eminent scientist, hero and friend died
2nd October 2012. In H. Nyborg (Ed). The Life History Approach to Human Differences: A Tribute to J.
Philippe Rushton. London: Ulster Institute for Social Research.
[4] Rushton, J. P.,
Bons, T. A., & Hur, Y.-M. (2008). The genetics and evolution of a general
factor of personality. Journal of
Research in Personality, 42, 1173–1185 or Rushton, J. P. & Irwing, P. (2008).
A General Factor of Personality from two meta-analyses of the Big Five. Personality and Individual Differences, 45:
679-683.
[5] See, Lynn, R.
(2011). Dysgenics: Genetic Deterioration
in Modern Populations. London: Ulster Institute for Social Research.
[6] Simonton, D.
(2009). Varieties of (scientific) creativity: A hierarchical model of
domain-specific disposition, development, and achievement. Perspectives on Psychological Science, 4, 441-452.
[7] Bugental, D.,
Corpuz, R. & Beaulieu, D. (2014). An Evolutionary Approach to
Socialization. In J. Grusec & P. Hastings (Eds). Handbook of Socialization: Theory and Research. Guildford
Publications.
[8] Deary, I., Batty, G. D. & Gales, C. (2008).
Childhood intelligence predicts voter turnout, voter preferences and political
involvement in adulthood; the 1970 cohort. Intelligence,
36: 548-555.
[9] For a more detailed
discussion of these associations, see, Lynn R. & Vanhanen, T. (2012). Intelligence:
A Unifying Construct for the Social Sciences. London: Ulster Institute for
Social Research.
[10] Shamosh, N. A. & Gray, J. R. (2008). Delay
discounting and intelligence: a meta-analysis. Intelligence, 36: 289-305.
[11] See Lynn, R.
(2011). Dysgenics: Genetic Deterioration
in Modern Populations. London: Ulster Institute for Social Research.
[12] Kaufman, S., DeYoung, C., Reiss, D. & Gray, J.
(2011). General intelligence predicts reasoning ability for evolutionarily
familiar content. Intelligence, 39:
311-322.
[13] For a more
detailed introductions to intelligence see, Dutton, E. (2012). Religion and Intelligence: An Evolutionary
Analysis. London: Ulster Institute for Social Research, Ch. 4; Neisser, U.
et al. (1996). Intelligence: knowns and unknowns. American Psychologist, 51: 77-101; Eysenck, H. J. (1992). Know Your Own IQ. London: Penguin; Jensen,
A. R. (1998). The g Factor: The Science
of Mental Ability. Westport: Praeger. For ‘reaction times’ and intelligence
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[15] Herrnstein, R. & Murray, C. (1994). The Bell
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[17] Lynn, R. (2011). Dysgenics: Genetic Deterioration in Modern
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[18] Bouchard, T. J. (1998). Genetic and
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[19] Miller, G. (2011).
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[20] See, Hamilton, W. (1996).
The Narrow Roads of Gene Land. Oxford:
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[22] See, Dutton, E. (October
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[23] Millard, A.
(2010). Probability of descending from Edward III.
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Ulster Institute for Social Research.
