University Essay: Evaluating Flynn's Work on Human Intelligence

This essay critically evaluates James Flynn's arguments on the contributions of genes and environment to human intelligence (HI), drawing on his 40 years of research, including his reflections from 2018. The essay explores Flynn's engagement with previous research, particularly Arthur Jensen's work, and the "Flynn effect," which revealed significant IQ gains over time. The essay delves into the Dickens and Flynn model, sociological arithmetic, and the interplay of social and individual multipliers in shaping intelligence. It examines Flynn's perspectives on the role of genes and environment, and how they interact to influence cognitive skills and IQ variance. The analysis also includes a discussion of the unshared environment and its impact on IQ variance. Ultimately, the essay aims to provide a comprehensive understanding of Flynn's insights into the complex relationship between genetics, environment, and human intelligence, highlighting the evolution of his ideas and their implications.

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Abstract
James Flynn has studied the association between genes and environment and human intelligence
(HI) for over 40 years with particular inspiration from previous authors such as Arthur Jensen in
1977. Jensen’s found out that there was no environmental justification of the IQ variance
between African American and whites; an aspect that worried Flynn causing him to conduct
more studies on the same. Flynn later demonstrated through the “Flynn effect” that there had
been immense IQ gains. The Dickens and Flynn model later proved that the essence of IQ gains
could not be ignored as much as they were not g gains. Based on the current improvements, the
author offers in-depth insight into the contribution of genes and environment on HI.
Introduction
The influence of genes and the setting on HI has been an area of study by Flynn for over 40
years. The research was sparked by the findings of Arthur Jensen in 1977 on how the frailties of
the environment within cohorts proposed similarity in the weakness between groups. To Flynn,
this was an indication that there was no environmental justification of the IQ variance between
blacks and whites. Moreover, it meant that the impact of environment between cohorts could be
disregarded. It is such discrepancies from previous research that prompted Flynn to conduct
further in-depth studies on the relationship between genes and environment and HI. The author
cross-examined several authors in the field to come with a comprehensive view. The objective of
this essay is to examine the arguments of Flynn (Flynn, 2018) about the comparative input of
genes and the environment to HI for the past forty years.
Flynn’s opinions on the role of genes and environment to HI are as a result of 40 years of
research based on previous researchers with a particular emphasis on Arthur Jensen’s research.

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Flynn’s arguments revolve around Jensen’s arithmetic, the Dickens/Flynn model, Lewontin and
arithmetic which results to the development of the sociological arithmetic as a solution to the
discrepancy that arises from the previous models. According to Jensen, genes and environment
plays a key role in explaining the black-white IQ gap. The author used identical twins; born and
brought out in a different environment, to prove his point. The author argued that if only the
setting caused the IQ variations, then the twins should develop with relatively similar IQ, and if
the genes were the single cause, they should develop with identical IQs. The outcomes of the
twin studies indicated that the environment was less significant than genes in determining human
intelligence. However, Flynn was not content with the conclusion of Jensen on the role of genes
and settings on HI. Thus, prompting him to use a social science model with his own life as an
example. He considered the environmental factor to be ‘the years of schooling’. According to the
findings of Flynn, genes did not render schooling as a weak factor within and between the cohort
group (the generation of Flynn and that of his father). In other words, the genes in the family of
Flynn accounted for much predictability with environment accounting for little.
The Dickens/Flynn model was designed to solve the problem of environment weaknesses within
a generation and environment. The model explains the value of genes within a cohort of same
age the idea of individual multiplier (IM) and social multiplier (SM) to explain the strength of
the setting. The authors used identical twins and found out that better genes place someone in a
better environment which further promotes one's performance or skill. An advantage of a good
gene at birth is that it is reproduced into a greater benefit in adulthood, hence called an IM. On
the other hand, an improved environment boosts performance or skill which further forces the
person to adjust to its level, and that develops even better quality of output, and thus becomes an
advantage to the individual, and such a setting improves one’s output, creating a much more

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improve the setting etc. This is termed as a social multiplier. An application of this model would
be ideal at the school performance. It is likely that genetic quality will determine how one will
respond at school, work hard, the kind of clubs to join, what university to attend among others. in
other words, one’s genetic quality will finally tend to match similar quality setting for cognition.
Genes envisage both the settings and IQ with the former alone predicting very little.
The above discussion proof that the equation of Jensen could not account for the gap that
distinguishes within the generation and between the generation. His equation assumes that each
gene implies the same IQs due to social multiplier. Therefore, it is completely wrong to use a
similar equivalence as suggestive of the function of speed against method and strength when
modelling something different. Hence the need for another equation in which speed has a
significant function addresses between-group variations in a mean IQ. Hence the proposal of
sociological arithmetic by Flynn. While still observing arithmetic rules, the author used
sociological factors to explain the environmental differences between-group IQ breaches. Flynn
uses them to contend that African Americans have not fully adopted the common culture than
white Americans (Flynn, 2008). It is easier to find out the social factors that distinguishes
cohorts. An example is formal schooling as observed by Luria who notes that it accustoms one to
classify and use logic on abstractions. Recent research indicates that the variations between the
IQ of cohort groups from the same population are based on age (Sta , Hogan, & Whalley,ff
2014). Using the Raven’s progressive matrices as a standard of measure of IQ of different
cohorts, multiple factors that cause IQ gains were observed (Flynn, 2012). Improved home
environment (in most cases improve the quality of school) led to increased IQ gains of
approximately 0.25 annually. The school years would be equal for both cohorts aged 11, which
would perform like a leveller. The additional years of school in the second group were

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worthwhile by 0.50 points annually. By age 17.5-24 (young adulthood) most had completed high
school and enrolled for university. Based on the Dickens-Flynn model, the present environment
destroys the impacts of previous settings, and as a result gains are not summative but instead
substitute each other.
Social change leads to fluctuations in the mean IQ one generation to the other. Society influences
the development or cognitive skills with regard to its own priorities. An example is that in which
taxi drivers (who have to locate their way around the big city) and bus drivers (who use fixed
routes) in London were compared with regard to mapping skills. The taxi drivers had enlarged
hippocampus the more years they served. The relative benefits on the two skills were all about
modifying social preferences and not g. Jensen found out that neural speed was much higher for
sharp students than the average person. Meaning the more intricate the task, the greater the
benefit, and thus the neural speed highly correlates with g. Flynn disagrees with this concept
because it lends g some particular importance that overrides gains on given cognitive skills when
in the actual fact they do not comprise g gains. The demand for the use of a given skill in the
society causes the brain to respond accordingly, and this is true for every cognitive sill and not
limited to those with significant g-loading such as working memory but also those with low g
loading.
In the study of the association between environment and genes between groups, there exists an
unshared environment which accounts for approximately twenty percent of IQ variance (Flynn,
2016; Haworth et al., 2010). This implies that it is often left unassociated with either variables or
a combination of both. There is a possibility of bad luck even amongst identical twins
irrespective of their good genes or environment. One can be subjected to unfavourable
surrounding thus suppressing the manifestation of the good genes. Therefore, the concept of IQ

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variance is usually perceived as the outcome of chance. However, it is in appropriate to opine
that twenty percent of this is just by chance because it is difficult to accurately determine. For
example, when a bright academic person joins the army it is perceived that he has gone for an
substandard setting, whereas when an individual who never performed well academically
chooses to be enrolled in a higher institution of learning, the individual has selected a standard
setting. Such choices are affected by genes for IQ, however, the usual presence of unusual
environment variance is a warning that some of them are just due to good choice.
conclusion
Flynn’s opinions on the role of genes and situations on HI are as a result of 40 years of research
based on previous researchers with a particular emphasis on Arthur Jensen’s research. In contrast
to Jensen’s findings, the genes in the family of Flynn accounted for much predictability with
environment accounting for little. The discrepancy in the problem of environment weaknesses
within a generation and environment were addressed using the Dickens/Flynn model which
explicates the value of genes within a cohort using the idea of IM and SM to explain the strength
of the situation. Based on the model, genes predict both the environment and IQ with the
environment alone predicting very little. Jensen’s arithmetic equation could not account for the
gap that distinguishes between and from the between-generation, hence the need for sociological
arithmetic by Flynn to address the discrepancy.

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References
Flynn, J. R. (2008). Where have all the liberals gone? Race, class, and ideals in America.
Cambridge, England: Cambridge University Press.
Flynn, J. R. (2012). Are we getting smarter? Rising IQ in the twenty-first century. Cambridge,
England: Cambridge University Press.
Flynn, J. R. (2016). Does your family make you smarter? Nature, nurture, and human autonomy.
Cambridge, England: Cambridge University Press.
Flynn, J.R. (2018). Reflections about intelligence over 40 years. Intelligence, 70, 73-83.
Haworth, C. M., Wright, M. J., Luciano, M., Martin, N. G., de Geus, E. J., van Beijsterveldt, C.,
& Plomin, R. (2010). The heritability of general cognitive ability increases linearly from
childhood to young adulthood. Molecular Psychiatry, 15, 1112–1120.
Staff, R. T., Hogan, M. J., & Whalley, L. J. (2014). Aging trajectories of fluid intelligence in late
life: The influence of age, practice, and childhood on Raven's progressive matrices.
Intelligence, 47, 194–201.