The Intelligence Paradox: Why the Intelligent Choice Isn't Always the Smart One - Satoshi Kanazawa 2012
Brief Histories of Alcohol, Tobacco, and Drugs
Why Intelligent People Drink and Smoke More
Recall from the Introduction that one of my major goals in this book is to break the equation of intelligence with human worth and to demolish the myth that intelligence is universally good and that more intelligent people are universally better at everything than less intelligent people. For this purpose, an interesting test case involves the consumption of alcohol, tobacco, and drugs, because it is widely agreed that their consumption—especially their excessive use—has largely negative health consequences. If I can demonstrate that more intelligent individuals are more likely to consume these substances to excess, then I would have gone a long way toward demonstrating that more intelligent people don't always do the right thing and, in fact, more intelligent people are often more likely to do stupid things.
In this chapter, I'm therefore going to discuss drinking alcohol, smoking cigarettes, and using illegal drugs. While, once again, science does not make any value judgment, it would be very difficult to make the case from any perspective other than strictly scientific that these activities are neither good nor bad. We know the health hazards of drinking, smoking, and taking drugs. Although the current consensus of medical researchers appears to be that drinking alcohol in moderation may have some health benefits, you will see below that that's not what I am talking about. I will be talking about getting drunk and binge drinking, which have no discernible health benefits.
So, unlike all the preferences and values I have discussed so far in this book, drinking alcohol, smoking cigarettes, and taking drugs, especially to excess, are all inherently bad for health. But the Intelligence Paradox is not about good or bad (healthy or unhealthy) values and preferences. All that matters is their evolutionary novelty. No matter how bad they may be, the Intelligence Paradox would nevertheless predict that more intelligent individuals are more likely to value and prefer them if they are evolutionarily novel. So the question is, are they?
Brief Histories of Alcohol, Tobacco, and Drugs
Alcohol
The human consumption of alcohol probably originated from frugivory—consumption of fruits.1 Fermentation of sugars by yeast naturally present in overripe and decaying fruits produces ethanol, known to intoxicate birds and mammals that consume them.2 However, the amount of ethanol alcohol present in such fruits ranges from trace to 5%, roughly comparable to light beer (0—4%). It is nothing compared to the amount of alcohol present in regular beer (4—6%), wine (12—15%), and distilled spirits (20—95%).
“Ingestion of alcohol, however, was unintentional or haphazard for humans until some 10,000 years ago,”3 and “intentional fermentation of fruits and grain to yield ethanol arose only recently within human history.”4 The production of beer, which relies on a large amount of grain, and that of wine, which similarly require a large amount of grapes, could not have taken place before the advent of agriculture around 8,000 BC. Archeological evidence dates the production of beer and wine to Mesopotamia at about 6,000 BC.5 The origin of distilled spirits is far more recent, and is traced either to the Middle East or China at about 700 AD. The word alcohol—al kohl—is Arabic in origin.
“Relative to the geographical duration of the hominid lineage, therefore, exposure of humans to concentration of ethanol higher than those attained by fermentation alone [i.e., at most 5%] is strikingly recent.”6 Further, any “unintentional or haphazard” consumption of alcohol in the ancestral environment, via the consumption of overripe and decaying fruits, happened as a result of eating, not drinking, whereas alcohol is almost entirely consumed today via drinking. So there appears very little doubt that drinking alcohol of any measureable concentration is evolutionarily novel.
Tobacco
The human consumption of tobacco is more recent in origin than that of alcohol. The tobacco plant originated in South America and spread to the rest of the world.7 Native Americans began cultivating two species of the tobacco plant (Nicotiana rustica and Nicotiana tabacum) about 8,000 years ago.8 The consumption of tobacco was unknown outside of the Americas until Columbus brought it back to Europe at the end of the 15th century.9 The consumption of tobacco is therefore of very recent historical origin and is definitely evolutionarily novel.
Drugs
Most psychoactive drugs have even more recent historical origin than alcohol and tobacco. “Before the rise of agriculture, access to psychoactive substances likely was limited.”10 The use of opium dates back to about 5,000 years ago,11 and the earliest reference to the pharmacological use of cannabis is in a book written in 2737 BC by the Chinese Emperor Shen Nung.12 Most other psychoactive drugs commonly in use today require modern chemical procedures to manufacture, and are therefore of much more recent origin. Morphine was isolated from opium in 1806.13 Heroin was discovered in 1874.14 Cocaine was first manufactured in 1860.15 It is therefore safe to conclude that most psychoactive drugs in use today are evolutionarily novel and very recent in historical origin.
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Given that the consumption of alcohol, tobacco, and psychoactive drugs is all evolutionarily novel—unknown before the end of the Pleistocene Epoch 10,000 years ago—the Intelligence Paradox would predict that, perhaps contrary to common sense and the unquestioned assumption that intelligent people make “smart” choices in life, more intelligent individuals are more likely to consume all such substances than less intelligent individuals. Both NCDS and Add Health allow me to examine the effect of childhood intelligence on adult substance use.