Until about a century and a half ago, serious studies were published in respectable scientific journals regarding the correlation between the skull sizes of people and their intelligence. Some people went even further and inferred the mental abilities of people from the shape of their face.
A few decades later, when Darwinism entered the mainstream, many known researchers were pushing purely hereditary systems of intelligence, proposing to sterilize mentally ill, or just "funny looking" people in order to prevent them from reproducing.
Finally, in the 20th century (and probably up until today) research has been focusing on devising test that will assess intelligence in a single number, nowadays called IQ.
These are the topics discussed in great detail in this book. Prof. Gould obviously took this issue seriously, and produced an amazing scope of research on the subject of measuring human intelligence. Actually, the book is so packed with information and facts, that it almost feels like a long scientific paper, which makes some portions burdensome to read. Along with presenting the history of intelligence testing in detail, Gould focuses on two important topics which are the main theme of the book.
One is the unavoidable skew and prejudice that inevitably seeps into many scientific researches, and more often than not reflects the cultural patterns of the era in which the research was conducted. For example, in the 19th century when
craniometry was the leading "tool" to try and measure intelligence, many works were skewed by racial prejudice. Researches would, knowingly and unknowingly finagle data to try and "prove" that blacks are inherently inferior to whites, French are superior to Germans, Germans are superior to French, et cetera. In the early 20th century, crude written and oral intelligence tests (which later evolved into the
Stanford Binet IQ test) were used as a weapon of people who tried to prove that immigration into America is bad because it lowers the average intellectual level of the residents.
The other is the inherent will of humanity to reify everything (
Reification is the attempt to treat abstractions as concretes), sometimes unjustifiably. In the context of the book, an especially unforgivable reification is trying to quantify something as obviously complex and multi-dimensional as human intelligence in a single number. Here is a quote from the book (pp. 252) that describes this well:
The temptation to reify is powerful. The idea that we have detected something "underlying" the externalities of a large set of correlation coefficients, something perhaps more real than the superficial measurements themselves, can be intoxicating. It is Plato's essence, the abstract, eternal reality underlying superficial appearances. But is is a temptation we must resist, for it reflects the ancient prejudice of thought, not a truth of nature.
Although this book is a bit heavy, it still makes an interesting read, since it gives a rare insight into the sometimes forgotten motives that invariably involve themselves into science. Although in theory science is objective, quite often personal motives, prejudices and just plain subjective patterns of thought creep in, and it is important to know when this happens in order to be able to see the facts clearly.
Eli Bendersky's website