The nature of human intelligence, the issue that has always been of great interest of a
number of scientists, psychologists and philosophers. What forms the basis of human
intelligence? Does genetic heritability determine differences in intellectual development?
And what does IQ heritability mean for race issue? These are the questions that the authors
of “the Bell Curve: Intelligence and Class Structure in American Life“, Richars J.
Herrstein,a psychologist, and Charles Murray, a political scientist, columnist, pundit, focus
on. The reason why the book created bitter disputes is the authors' argument that “...both
genes and the environment have something to do with racial differences“ (Cognition 56
1995:99-128) that some scientists called „scientific racism“.
The authors claim that intelligence is heritable, i.e. variations in intelligence are to a wide extent predicted be genes that people inherit. Thouhg they don't deny the influence of environmental factors. It follows thence that heritability can be divided into so-called narrow-sense heritability and broad-sense heritability. According to Neven Sesardic, the author of “Making Sence of Heritability“, the first type is based on the additive effect of genes that exclude any kind of interaction: between genes or between genes and environments, while broad-sense heritability, on the contrary, is premised on the assumption that genes and environments don't act separately, but at the same time there is no concrete evidence to what extent this interaction affects the heritability of IQ (Sesardic 2005:49).
I am not quite sure, but I am inclined to think that broad-sense heritability is more a theoretical issue, because it is difficult to draw a boarder between genetic and environmental influence on the intelligence. What has more impact in one particular case? And can we talk about genetic heritability at all if it turns out that environment has a defining role in the development of characteristics of a person.
The authors claim that intelligence is heritable, i.e. variations in intelligence are to a wide extent predicted be genes that people inherit. Thouhg they don't deny the influence of environmental factors. It follows thence that heritability can be divided into so-called narrow-sense heritability and broad-sense heritability. According to Neven Sesardic, the author of “Making Sence of Heritability“, the first type is based on the additive effect of genes that exclude any kind of interaction: between genes or between genes and environments, while broad-sense heritability, on the contrary, is premised on the assumption that genes and environments don't act separately, but at the same time there is no concrete evidence to what extent this interaction affects the heritability of IQ (Sesardic 2005:49).
I am not quite sure, but I am inclined to think that broad-sense heritability is more a theoretical issue, because it is difficult to draw a boarder between genetic and environmental influence on the intelligence. What has more impact in one particular case? And can we talk about genetic heritability at all if it turns out that environment has a defining role in the development of characteristics of a person.
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