European Journal of Personality
Eur. J. Pers. 21: 767–787 (2007)
Published online in Wiley InterScience
(www.interscience.wiley.com) DOI: 10.1002/per.658
Author’s Response
The Big G-Factor of National Cognitive Ability
HEINER RINDERMANN*
Institute of Psychology, Otto-von-Guericke-University Magdeburg, Germany
Abstract
The response deals with several controversial issues: theoretical concepts of cognitive
abilities, their cultural relativity in definition or level, the meaning and validity of national
cognitive ability, methodological questions like the ecological fallacy, the variance of
intelligence at different levels of observation, multi-level analysis, the correctness and
importance of levels of analysis in cognitive-ability research, the aggregation and
adjustment process, and the similarities of different cognitive assessment approaches.
Central to this research are questions of causality (the causes and consequences of
national cognitive-ability homogeneity and level), of malleability of these levels, and of
ethical and political consequences of intelligence research. Copyright # 2007 John Wiley
& Sons, Ltd.
First I want to express my gratitude to all of the commentators. Even though some do not
agree with the essence of the presented paper, all of the commentators and critics show a
thorough analysis of the paper. The contributions help to form, assess, rethink, clarify and
improve lines of thought and empirical research.
THEORETICAL ISSUES
Demetriou presented a theoretic definition of the statistical phenomenon g as ‘Speed of
processing, control of processing, representational power, inference and self-awareness
self-regulation’. My definition of intelligence deals only with complex cognitive abilities.
Basic cognitive abilities like mental speed, attentional control or (at the boundary between
basic and complex) working memory are prerequisites for complex thinking abilities, but
*Correspondence to: Heiner Rindermann, Institute of Psychology, Otto-von-Guericke-University, Magdeburg,
Germany. E-mail: [email protected]
Copyright # 2007 John Wiley & Sons, Ltd.
768
Discussion
not identical with them. Such a position can be justified theoretically and is supported
empirically by higher g-loadings of more complex tasks (Flynn).
In my view, intelligence is understood as the complex ability to think: It is the ability to
solve new cognitive problems by thinking (without relying on pure recall of knowledge),
to infer (to draw inductive and deductive-logical conclusions, reason), to think abstractly
(to categorise, to sort out information, to process abstract information in the form of verbal
and numerical symbols, in the form of abstract figures and in the form of general rules) and
to understand and realise (to recognise and construct structures, relationships, contexts and
meaning).
The main problem with this definition is its distinction from knowledge. Certainly pure
recall of knowledge is excluded, but knowledge is necessary for reasoning, helps in
abstract thinking and is especially important for all processes of understanding.
Additionally, knowledge is always required to solve the kinds of tasks confronting
individuals in everyday life or appearing in cognitive-ability tests. Conversely, thinking
ability helps to increase and use knowledge. The g-factor always refers at least to some
degree to both thinking ability and knowledge. Fluid intelligence tests consisting of
school-distant material (no verbal and no numerical content, no knowledge questions) rely
more on thinking ability, other cognitive-ability tests (intelligence or student assessment
tests) rely more than fluid intelligence tests on knowledge (e.g. WAIS, TIMSS). As
De Fruyt mentioned, the switch from knowledge to competence measurement in student
assessment studies has increased their correlations with intelligence tests, which are
usually constructed with the intent to measure thinking ability.
B. Spinath pointed to one central theoretical aspect: ‘If intelligence is defined as the
ability to think, this definition does embrace all cognitive competencies, no matter how
context-specific these competencies are’. This does not mean that we cannot distinguish
between different content-based scales (school- and knowledge-near verbal vs. numerical
vs. school-distant scales) for some theoretically justified research questions (e.g. sex
differences, cultural/ethnical differences, effects of instruction) or for students’
counselling, but intelligence tests and student assessment tests should not be distinguished
any longer. Obviously, all assessment tests with different names are intended to measure
something different; this is true within the tradition of intelligence tests too.
Prenzel and Walter pointed out that high correlations between variables do not imply
that the two variables represent the same phenomenon, with examples taken from medical
research (body size and body weight; or from meteorology: lightning and thunder). These
pairs of variables are highly correlated, but they represent different theoretical concepts
and empirical phenomena. In agreeing with this position, I note that we need task and
cognitive analyses, analyses of the cognitive demands of items and the problem-solving
processes used for answering them to determine the content validity of both intelligence
and student assessment scales. This is an important topic for future research, and there
already exist some studies investigating this within the large-scale assessment tradition
(e.g. Woschek, 2005).
CULTURAL RELATIVITY
Helfrich and Hunt have referred to the possible cultural relativity of intelligence
concepts: ‘What is considered as ‘‘intelligent’’ refers to the successful adaptation to those
cognitive tasks which are significant within a specific culture’ (Helfrich). ‘It can be argued
Copyright # 2007 John Wiley & Sons, Ltd.
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769
that intelligence, as evaluated by these tests, is a Western concept, and that the abilities
evaluated by the tests may not be the ones valued by non-western societies’ (Hunt). Yet,
both authors understand (as I do) intelligence as a cognitive ability. Non-cognitive
behaviours such as relying on tradition and listening to the elderly (as in some concepts in
African cultures) are not included.
To continue this line of argument, not only does the definition of intelligence depend on
culture, but the level of cognitive ability itself does as well, and perhaps the definition of
intelligence depends on the level of intelligence too: The esteem for intelligence—as a
cognitive competence, as the ability to solve new cognitive problems by thinking (and not
e.g. by authority), as thinking abstractly (see the affinity to Piagetian formal-operational
thinking), as drawing correct inductive and deductive-logical conclusions and as
understanding—helps through cognitive stimulating education and practice of thinking
in everyday life to improve cognitive ability.
If others or other cultures use the word ‘intelligence’ to refer to different or
opposite concepts, it would help to use other terms (e.g. ‘traditionalism’ or
‘traditionality’). Finally, an etymological analysis of the term ‘intelligence’ (see
Rindermann, 2007a) shows that Latin intellegentia and intellegere (inter-legere) and
Greek legein and oo& stand for rational ways of thinking and understanding the world.
The development of this idea seems to be interdependent with autonomy, rule of law and
(at least mental) liberty.
MEANING AND VALIDITY OF NATIONAL COGNITIVE-ABILITY LEVEL
Several comments deal with the meaning of the aggregated intelligence and knowledge
data (Bosker, Brunner & Romain, Volken). Volken retorted: ‘Macro-level entities
cannot be intelligent, unless one is referring to intelligence metaphorically’. Of course, the
mean intelligence per passenger of a car is not the intelligence of the car. Basically,
national cognitive-ability levels can have two meanings: (a) the means of individuals
within those nations, (b) the levels of intelligence of the nations themselves (of institutions
like rational bureaucracies, universities, etc.). The preferred meaning here is the means of
individuals within those nations.
Similarly, in economic research mean GNP per capita of a country is a well-established
concept. National intelligence and mean intelligence are analogous to national wealth and
GNP per capita. Alternatively, the sum GNP of a country reflects (apart from productivity)
the size of the country; for the cognitive domain, the number of universities or issued
patents would be analogous. Per capita (mean) values are normally more useful.
Allik claimed that denying cognitive ability differences across cultures and nations is no
longer possible. But it seems that Brunner & Romain and somehow Helfrich are still
denying them. For example, Brunner & Romain maintained that national cognitive
competence levels stand for wealth, not for the ability to think or knowledge. Naturally,
variables are indicators of all characteristics correlating with them, independent of the
causes of these observed correlations, e.g. national cognitive abilities correlate with
wealth, modernity, quality of schooling, skin colour, latitude, etc. (I will deal with causal
questions below).
How should we refer to national cognitive-ability levels? Asendorpf used the term
‘big G-Factor’ for the statistical results, Hunt ‘national cognitive competence’ for
the construct. Both expressions are applicable for statistical results or for the construct.
Copyright # 2007 John Wiley & Sons, Ltd.
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Discussion
I will use national or macro-social cognitive ability for national cognitive competence,
which I will abbreviate as national intelligence (though I mean it to include knowledge).
I mean by this a general complex cognitive ability to think and use important knowledge
correctly.
Wicherts & Wilhelm questioned the validity of sub-Saharan Africa test scores. (‘The
IQ values for African countries are consistently too low’.) Results for sub-Saharan
countries are the lowest and also of the worst quality. Within-continent differences in subSaharan Africa are perhaps not valid, and it is not appropriate to assign their populations
terms for low intelligence of psychiatric–neurological origin (‘mental retardation’,
‘debility’; see also Jensen, 1998, p. 367ff.), but I do not believe that the scores at the
general level are largely incorrect: The low values correspond to too many other variables
and aspects standing for low cognitive abilities like results of student assessment and
Piaget studies (e.g. Botswana in IEA-Reading 14-year-old pupils 1991 330, as IQ 75;
South-Africa in TIMSS 8th graders 1999 259, as IQ 64; Ghana in TIMSS 8th graders 2003
266, as IQ 65; South-Africa in TIMSS 8th graders 2003 254, as IQ 63; plausibility
considerations lead to lower results for the youth of Africa because of low school
attendance rates and unrepresentative participation of countries), poor quality school
systems, high skipping rates, low rates of high school degrees, low patent application rates,
no famous universities, and many reports of everyday behaviour from officials, traders,
journalists, ethnologists and other scientists in 19th century to this day such as belief in
witchcraft, use of Sangomas, etc.
This does not mean that intelligence in Africa could not be enhanced easily, at least at
the lower levels, through training (Skuy, Gewer, Osrin, Khunou, Fridjhon, & Rushton,
2002) and better nutrition (Whaley et al., 2003). It also does not mean that there is no
Flynn effect (Daley et al., 2003). But there are still some strange empirical phenomena in
the cognitive-ability research in non-western countries such as university students with
average IQ’s of 77–78 in South Africa (in psychology 84, in math 100, in engineering 103;
Rushton, Skuy, & Fridjhon, 2003), or Yanomami Indians who cannot solve one item in the
SPM (personal observation by Rindermann [2001] in Brazil). These results correspond to
the low achievement outcomes of former generations in the Western World and the dispute
about their origins is similar to the frequent discussion of the validity of inter-generational
differences (Flynn, 2007).
In contrast, natives of these low-scoring countries demonstrate levels of ability
unimaginable to Western people to orient themselves in nature (see Lewis, 1976, or old
reports of ethnologists like Von den Steinen in the 19th century). These observations are
confirmed by many other empirical data (test studies and observations of everyday
behaviour by others). The level of teaching in universities seems to be highly adaptable in
both directions to the competencies of students (and perhaps to the intelligence and
knowledge of the instructors too); the competence levels implied by given degree levels
vary widely, even within countries. We need further behavioural observations to validate
test results and to give them more credibility and persuasiveness within science. Some
preliminary remarks have been presented in the paper and response.
METHODOLOGICAL ISSUES
Several authors were concerned about the ecological fallacy problem (see Allik,
Asendorpf, Bosker, Helfrich, and Figures 1 and 2). Others stressed that the variance in
Copyright # 2007 John Wiley & Sons, Ltd.
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intelligence (or in student assessment results or in genes) is greater at the individual level
than the variance at the national level (Johnson, F. Spinath).
I agree that there is a fundamental difference between correlations at the national (or
other aggregated levels) and the inter-individual (or intra-individual) level. Indeed, there is
no logical relation between correlations at different levels (see King, 1997). Personality
data, whose measurement depends on effects of framing of reference (Leung & Bond,
1989), is especially subject to inconsistent relations. However, in empirical research we
rarely look for logical generalisation or inference, but frequently for inductive
generalisation and generalisations supported by plausibility. For this kind of generalisation
theoretical justifications and empirical findings are necessary (see below).
Second, caution is necessary in inferring causation from correlations in nonexperimental studies. For causal interpretations we need (a) a correct explanatory theory
and (b) support from results of corresponding studies that further control for important
possible causal factors and (c1) done in different country samples and (c2) by different
researchers (c3) at different levels (successful replications). The strongest evidence would
come from (d) cross-lagged panel studies (including control for important alternative
causal factors) analysing reciprocal effects. Blind interpretations of correlations are not
only unusual but also could lead to inappropriate conclusions.
The simultaneous multi-level factor analysis recommended by Bosker and Wicherts &
Wilhelm requires inclusion of all tests, from intelligence tests through TIMSS and PISA,
in one sample of pupils across countries. So far data for this kind of analysis are not
available. Within PISA or within TIMSS it would be possible today. But the objection to
my conclusions that the analysis should be multi-level runs the risk of becoming a mantra,
sometimes raised where no data are given, sometimes where the samples are too small,
sometimes connected with the demand to interpret significance levels, standard errors and
confidence intervals (which are correct only by use of multi-level analyses and software
like HLM, Mplus and others). But the use of inference statistics at the level of nations is
not very sensible. More meaningful as a proof against chance and test of generalisability
(both standing as indicators for truth) would be the proof of robustness of results across
different national samples, test samples, and measurement points, and tests of the stability
of results after consideration of additional factors.
In the international student assessment studies, the aim is to analyse populations, not
individuals. Research questions at the national level are important, especially because of
the relevance of cognitive abilities to the development of nations (see below). Similar
questions at the national level are meaningful in other fields, e.g. why is it less warm in
Norway than in Spain? Obviously, additional factors within countries are important, such
as sea level (in the mountains it is colder than at the coast), side of a valley (north or south,
east or west), season (winter or summer), and time of the day (in the morning or at
midday); nevertheless it remains important to understand why it is colder in northern than
in southern nations. This question could be analysed at the national level, even though
additional knowledge could be obtained by analysing within-nation differences. Nobody
would deny that.
In the target paper I recommended using sum values of different scales and studies.
Economists also use sum values in educational research (e.g. Hanushek, 2002, p. 14,
‘composite measure’). But several commentators see problems in the aggregation
process in computing sum values. Volken recommended the weighting of single scale
and study data by sample size and quality. He also questioned the estimation of missing
data. Prenzel, Schmitt, F. Spinath and, in personal communication, Flynn and
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Discussion
Wuttke expressed a suspicion that the adjustments I carried out were not perfect. In
agreement with these remarks, I believe that the aggregation and especially the
adjustment process I used could be improved. Maybe the results were slightly
overadjusted. But the results of analyses with unadjusted and adjusted data were
similar. The aim was to have valid values for students at school in a country, or agenormed for all youth or for the whole population of a nation (including immigrants and
adults). The adjusted means are intended to reflect age-normed levels for the whole
youth including immigrants. Indirectly, they should also apply to the adult population
(if reproduction and migration differences within the adults and between youth and
adults are not too large; Weiss).
Voracek mentioned that the Buj study is less suspect than some researchers may
believe. But the data of Vinko D. Buj seem not to be ideal for differences within Europe
because these data yielded correlations with student assessment studies of only around
r ¼ .10 to .07. In contrast, the mean IQs of the Lynn & Vanhanen collection (including
Buj) correlated with student assessment studies within Europe at r ¼ .61 (N ¼ 31; grade),
r ¼ .71 (N ¼ 29; age) and r ¼ .67 (N ¼ 35; student assessment sum, all corrected). As in
many other research fields, the aggregation of different sources of information increased
the quality of the data.
INTER-INDIVIDUAL DIFFERENCES
Several authors questioned whether the correlations at the national level are relevant for
psychological research because this research deals with individuals, their differences and
their development. Correlations at the individual level (inter-individual or intra-individual
differences) could be different from those at the national level (national differences). And
even similar correlations could have different causes (Allik, Asendorpf, Helfrich, Schmitt).
Of course, no cogent conclusions between the levels are possible, not from individual to
the national level and not from the national to the individual level. Correlations seem to be
unstable for (non-ability) personality variables (e.g. reading interest). Lynn and Vanhanen
(2002) have tried to show that correlations of ability measures with other similarly
objective variables at higher levels are in the same direction and normally, but not always
higher, particularly because of higher reliability through aggregation (see Asendorpf,
Bosker, De Fruyt, Walter).
Due to lack of space a detailed description of results at the individual data level was not
possible; further information can be found in Rindermann (2006, 2007a). But at present
correlations between TIMSS and PISA at the individual data level (Helfrich) are
unknown. To develop them, we need to administer the same tests to the same students.
This has not been done, but the author has asked for a grant (DFG) to do this research in
the future. This would make it possible to do factor analyses at the individual data
level (Walter) and perhaps multi-level analyses (Bosker, Wicherts & Wilhelm).
High correlations do not preclude some content-specific parts and relations to
environmental and genetic factors (see target paper and Helfrich, Walter, Wicherts &
Wilhelm).
In the target paper I described correlations and similarities between intelligence and
student assessment test results. Some commentators think that this position is a
controversial and perhaps rather revolutionary point of view. But a half century ago
Coleman and Cureton (1954) described high correlations between intelligence tests (Otis
Quick-Scoring Test Beta) and student performance tests (Stanford Achievement Test) of
Copyright # 2007 John Wiley & Sons, Ltd.
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r ¼ .83 and r ¼ .84. And 80 years ago, Kelley (1927, p. 64) spoke about the jangle fallacy of
using different words for the same thing: ‘The use of two separate words or expressions
covering in fact the same basic situation, but sounding different, as though they were in
truth different’. He found a correlation (corrected for attenuation) of r ¼ .90 between
intelligence and school achievement tests.
QUESTIONS OF CAUSALITY: CAUSES AND CONSEQUENCES
Causes for the homogeneity of the different intelligence and student assessment test results
could also be causes for the different levels of national cognitive competencies.
Additionally, we can distinguish between (a) the causes of the intelligence and knowledge
differences across nations and (b) the consequences of the intelligence and knowledge
differences across nations. The observation of correlations between abilities at the one side
and cultural, social, political, economic, geographical, educational and further environmental and biological (genetic) aspects at the other side is not enough. It is important to
know what causes what? Prediction of wealth (Allik) is fine, but science and successful
improvement require explanation.
Some authors described possible outcomes of high intelligence levels. Demetriou: ‘I
believe that going in this direction is a move away from the reasons that cause poverty,
misery and war within and between nations’. Motti-Stefanidi: Cognitive abilities like
‘reasoning and abstract thinking’ are helpful to cope with the cognitive challenges of
modern times, for the ‘countries’ economic advance’, for ‘facing up to the challenges
posed by globalisation’. Oesterdiekhoff: ‘Formal operations account for the development
of sciences, enlightenment, modern law systems, economic growth, humanism,
secularisation and a lot of other related processes’.
Possible causes were systematised by Meisenberg: ‘There are three possible causes for
the covariance of IQ and school achievement across countries: differences in national
school systems, differences in the non-school environment and genetic differences
between human populations. All three possibilities are theoretically plausible and are at
least somewhat supported by empiric evidence’. He adds a teacher intelligence factor for
school as well: ‘Most likely student performance depends not only on the student’s
intelligence but also on the teacher’s’ (see also Lynn et al., 2007). As mentioned earlier,
(a) the G-factor (high correlations) may depend on these factors or (b) the ability level
(or perhaps (c) both).
There exist two courageous attempts to use genetic factors besides environmental
factors to explain international cognitive-ability differences: Lynn understands ethnic
differences in intelligence to result from adaptation to the cognitive demands of survival
during the winter that evolved in the European and East Asian peoples. Rushton holds the
opinion that the r-K-theory can explain assumed genetic intelligence differences between
groups (‘genes influence group differences in about the same proportion as they do
individual differences within a group (i.e. about 50%)’, ‘both individual and group
differences are . . . caused by genetic as well as environmental influences’). These
hypotheses are backed up by correlations with the indicators skin colour (Meisenberg,
2004; Templer & Arikawa, 2006) and latitude (Meisenberg, 2003) at the macro-social
level. But at present the specific genes involved are unknown, and causal links at the
genetic–biological–neurological–psychological levels have yet to confirm these hypotheses (from genes to proteins via neurological functions to intelligence; see too Wicherts &
Copyright # 2007 John Wiley & Sons, Ltd.
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Discussion
Wilhelm). Classical twin studies cannot be used for the explanation of group differences
(F. Spinath) and they cannot answer these biological questions.
It could be asked why cold is a stronger environmental challenge than drought or
alternations of droughts and rainy seasons in areas such as Egypt, Mesopotamia, India and
Middle America. One response might be the necessity and possibility of keeping supplies
which is enabled by foresight (see the German proverb ‘Denk daran, schaff Vorrat an’.
‘Think of it, stock up on’.). Predictable and cognitively solvable environmental challenges
could stimulate evolutionary cognitive development; diseases like malaria were not part of
cognitively solvable environmental challenges in pre-modern times. Examples like
differences in lactose intolerance show the ongoing process of evolution and the important
differences in genes between groups.
Easily testable is the suspicion of Brunner & Romain that the national G-factor and
cognitive-ability levels are indicators of national prosperity. First, the correlations between
cognitive and educational levels are higher (r ¼ .78) than between intelligence and wealth
(r ¼ .63) or education and wealth (r ¼ .60). Second, the correlation between intelligence
tests and student assessment tests (r ¼ .86) remains after partialing out GNP (rp ¼ .76).
Third, the positive manifold still exists after partialing out GNP. The first unrotated factor
explains 81.8% of the variance, factor loadings on the G-factor are still high (see Figure 4).
Fourth, wealth, politics, and cognitive abilities load on different factors (Sternberg; see
Table 1). Fifth, there are reciprocal causes between intelligence and wealth (as expected by
Brunner & Romain) but longitudinal studies show stronger effects of cognitive ability on
wealth than of wealth on intelligence (Rindermann, 2007b). A little bit odd is this assertion
formulated by researchers in Luxembourg: Luxembourg has the highest level in GNP
worldwide but to this day is not famous for very good results in tests of cognitive
competence or other indicators for particularly high cognitive abilities.
The longitudinal results (Rindermann, 2007b) offer strong support for the human capital
theory (Hunt): ‘Consider Japan and South Korea. In less than half a century both countries
Figure 4. G-factor of cognitive abilities at national level (unadjusted data, GNP partialed out, 81.8% of variance
explained, FIML, N between 25 and 185 including estimated values, sample N ¼ 185 countries; see target paper).
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Table 1. Results of factor analysis of different attributes of societies
IQ-LV-06
Grade (TIMSS þ PIRLS)
Age (PISA, 00-03)
Literate adults
Secondary school
Years of school
GNP 1998 LV
GNP 2000
Democracy
Rule of law
Political liberty
Ability-education
Wealth
Politics
N
.79
.94
.91
.80
.77
.71
.37
.26
.33
.36
.21
.35
.27
.35
.19
.21
.42
.85
.93
.47
.64
.23
.12
.11
.22
.33
.26
.41
.25
.22
.67
.36
.88
193
65
48
172
117
107
185
184
183
131
186
Note: Coefficients equal or higher than ¼ .50 are printed in bold. Test values not adjusted. FIML, varimax,
sample N ¼ 194 countries. Data: see target paper and Rindermann (2007b).
rose from the devastation of war to become two of the most prosperous countries on the
globe, virtually entirely on the ingenuity of their people, for neither country is rich in
natural resources’. With all due modesty, the two Germanies and other countries of Europe
destroyed in the Second World War or Singapore and Taiwan could be examples too. In
historical economic research the comparison between Ghana and South Korea is often
used as an example (see Landes, 1998). Of course other factors besides cognitive resources
are still important for the development of wealth. Hunt: ‘A full understanding of the
importance of human capital will require understanding reflectivity, persistence and
personal discipline as well as understanding the narrower sorts of intelligence evaluated by
a 1- to 3-hour test’.
Some of these factors were described by Irwing (personality, knowledge, motivation
and psychopathology) and Sternberg (leadership, creativity, wisdom); Heckman (2000)
also advocates a wider concept of human capital. Economic and political factors
(economic freedom, ownership law, rule of law, etc.) are also important for growth.
Intelligence is never everything, and intelligence needs to be embedded in a towards merits
oriented society. Without meritocracy, the advantages of thinking and knowledge are lower
(Irwing). For example, meritocracy seems to be more realised in Britain (Nettle, 2003)
than in Germany (OECD, 2002, p. 67). Meritocracy is also necessary for the function of
public administration (as ‘Weberianness’, Evans, & Rauch, 1999) and for the efficient
employment of human resources (optimised allocation) in the private and public sector
(including universities and research). Some researchers (Bosker, also Weede, personal
communication) are of the opinion that abilities of the elite are more important for social
development. This thesis could be examined in further studies by using the percentages of
pupils and adults at the highest level in the OECD- and IEA-studies.
Thanks to Hunt for his reference to climatology: relationships at the macro-social level
are similarly complex; and intelligence research at this level is still young, starting with the
seminal works of Lynn and Vanhanen and the IEA- and OECD-studies.
Flynn proposed the hypotheses that modernity causes national cognitive growth and
that international differences in abilities depend on modernisation: ‘Since modernity sets
in action a process by which rising formal education and rising IQ reinforce one another by
reciprocal causality, between-nations comparison would blur distinctions between their
measures’. From this perspective, both the G-factor (high correlations) and the ability level
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Discussion
depend on modernisation. I suggest that modernisation may be an accurate description of
processes rather than a causal theory: modernisation is a phenomenon which needs
explanation by itself. The driving forces of modernisation are cultural and cognitive
factors. Passive and given wealth like in the rich Arab gulf states leads only to technical
modernisation achieved by foreigners from Asia (mainly India) and the West; similar
cognitive gains are not observed in these states. The assumed processes of reciprocal
causation (Flynn, Oesterdiekhoff) function only in societies where these processes are
self-made, coming from inside, at least some internal cultural-cognitive receptors must be
present to bring about this development.
Helfrich thinks that student assessments are not indicators of school quality because of
their high correlation with intelligence. I think this is not exactly correct, because
intelligence is also supported by school (Meisenberg, Sternberg; Ceci, 1991; Winship &
Korenman, 1997). Purer measurements of the effects of school can probably be obtained
by partialing out more school-distant intelligence measures (Meisenberg). Hence future
student assessment studies should include fluid intelligence tests (Meisenberg). At present
would be possible to partial problem solving out in PISA 2003. But this strategy could be
dangerous and faulty, because effects of education would also be eliminated: fluid
intelligence (e.g. measured by CFT) depends also somewhat on schooling (Stelzl, Merz,
Remer, & Ehlers, 1995).
Bosker raised a very important question about causality and level: ‘A child’s cognitive
development is by far more dependent on the family, peer, neighbourhood and school
context, than on regional and country-level factors’. The main problem with this position
is that it is only appropriate for inter-individual differences. It underestimates macro-social
effects: family, peers, neighbourhood and the school context themselves depend on
cultural and historical determinants! The strong effect of macro-social determinants has
been demonstrated by the secular rise of intelligence in the 20th century (‘Flynn effect’).
QUESTIONS OF MALLEABILITY
Linked to the question of the cause of the national cognitive-ability levels and their
differences is the question of malleability of (a) the national cognitive-ability levels or (b) of
the national differences. And even if absolute differences could be reduced, rank orders might
be preserved. Malleability or immutable innate capacity questions were raised by Johnson
and B. Spinath (‘Can we advance something that is heritable?’). In favour of malleability
were Asendorpf, Ceci & Williams and Demetriou; against it was Nyborg (‘resistant to
intervention at the individual, school or national level’). Probably Nyborg meant the
malleability of differences as rank orders and not the malleability of levels. To go with this
interpretation Demetriou referred to the plasticity of brains and malleability of national
cognitive levels (secular rise). Even a genetic determination does not deny modifiability
(Motti-Stefanidi; e.g. myopia can be corrected by the use of glasses or surgery).
However, the assertion of the relevance of environmental or cultural factors does not
imply that modification will be easy! For instance, how can education in families and
schools in Islamic or African countries be easily changed (e.g. UNDP, 2003), given their
emphasis on tradition and authoritarian rules? The strongest intervention in this respect
was instigated by Atatürk in Turkey, and it was not very successful according to measured
cognitive-ability results (IQ-LV-06 ¼ 90, TIMSS-99-8 ¼ 431, PISA-03 ¼ 427) and other
indicators of cultural modernisation.
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777
ETHICAL AND POLITICAL CONSEQUENCES OF INTELLIGENCE
RESEARCH AT THE NATIONAL LEVEL
Some comments dealt with the provocative nature of this research (Helfrich:
‘provocative paper’, B. Spinath: ‘explosive potential’). Is this kind of research
especially provocative, or is important social research always provocative because of its
impact on interests and philosophies of life? That intelligence and student assessment
tests are highly correlated is not really new (Ceci, 1991; Coleman & Cureton, 1954;
Kelley, 1927). Perhaps this research field is fruitful because researchers could make this
discovery anew every thirty years. It is not only (a) the homogeneity assumption that
seems to be provocative, but also (b) the assumption of differences between groups
(within and between nations) at the social, ethnical/racial, political or cultural levels,
(c) the assumption that these differences are causal factors for social development (from
wealth to health) and (d) the assumption that these difference are not due to chance but
caused by systematic determinants mainly be located within nations. This controversy
about causality reflects the old dichotomy between internal and external explanations,
between idealistic (e.g. cognitive-mental) and materialistic (e.g. economic) world
views.
Some authors have raised questions about the ethical and political consequences of
intelligence research at the national level (Allik, Asendorpf, F. Spinath). F. Spinath:
‘What is the scientific value of world maps of IQ differences or figures displaying negative
correlations of national cognitive level and, for example, percentage of Muslims in a
country?’ I hope it has become clear that the scientific and practical value is understanding
the outcomes for societies (e.g. human capital theory). Percentage of Muslims is an
important question because it shows the relevance of interdisciplinary research and
breadth of perspective in the field of intelligence research: religion is a cultural
determinant for the development of cognitive abilities; the esteem and practice of
education and thinking depends on religious, philosophical and cultural attitudes (for
Islam: Nagel, 1988; Renan, 1883; Tibi, 1992). Like being open to biological research,
intelligence and educational research could gain being receptive to findings from
sociological, historical and cultural research.
In accordance with a strong occidental tradition (starting with Greek philosophers like
Socrates, continued with renaissance humanist like Alberti, with enlightment and neohumanism, with idealism and conventional civil philosophy of life), my view is that
education (‘Bildung’ in the sense of development and stimulation of rational thinking by
oneself and in the sense of transmission of important and accurate knowledge) is the
primary way to autonomy and success in different aspects of the life of individuals and the
fate of societies. This kind of education depends on cultural values and belief systems.
Culture and education are not the only causes of today’s differences in cognitive abilities
between nations, but probably the most important ones.
Corresponding to this, Motti-Stefanidi has demanded educational reform (less rote
learning of information through repetition, less drilling and less solution of preconfigured
problem sets, more stimulation of the ability to think). Rote learning has an authoritarian
aspect and memory is not identical to the ability to think. Both from genetic (e.g. Weiss)
and environmental (e.g. Motti-Stefanidi) points of view, we need more offspring of better
educated and intelligent adults who will further cognitive ability through their education
and environment (language quality and quantity, authoritative parenting style, books,
support of school learning, etc.) as well as through their genes. Perhaps the easiest way to
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778
Discussion
accomplish higher macro-social cognitive-ability levels would be to increase the
availability of cognitively stimulating education for all.
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