De Gustibus Est Disputandum

De Gustibus Est Disputandum

SATOSHI KANAZAWA, Indiana University of Pennsylvania, 2001.

Principles of Evolutionary Psychology

Our preference for sweets and fats is an example of an evolved psychological mechanism (Barash 1982:144-47). Throughout most of human evolutionary history, procurement of sufficient calories to sustain our bodies physically was a particularly severe problem of adaptation (survival); malnutrition was a common problem. In this environment, those who had a “taste” for sweets and fats (which have higher calories) were better off physically than those who did not have the same taste. Those who had this taste therefore lived longer, led healthier lives and produced higher-quality offspring than those who didn’t. They in turn passed on their taste to their offspring, over many thousands of generations, until most of us living today have a strong preference for sweets and fats. (See Buss 1995:5-9 for other examples of evolved psychological mechanisms.)

Note that we do not consciously choose or decide to like sweets and fats. We just like them but otherwise don’t know why; sweet and fatty foods just taste good to us. […]

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Social sciences are branches of biology

Social sciences are branches of biology

Satoshi Kanazawa, 2004.

3. Puzzles: wage penalty for motherhood, wage reward for fatherhood (and bigger reward from boys than girls)

In a recent study, Budig and England (2001) find that mothers earn less than non-mothers with similar characteristics. The negative effect of motherhood on wage is greater for married mothers than for unmarried mothers. Their finding is in stark contrast to Lundberg and Rose’s (2000) discovery that fathers earn more than non-fathers with similar characteristics. In other words, there appears to be a wage penalty for motherhood and a wage reward for fatherhood.

Both Budig and England (2001) and Lundberg and Rose (2000) use a statistical technique called the fixed-effect model. By using two data points for each individual, before and after parenthood, the fixed-effect model controls for all unobserved heterogeneity, and allows these authors to rule out the possibility of selection bias. In other words, Budig and England (2001) demonstrate that it is not because women with lower earning capacities are more likely to become mothers that mothers earn less than non-mothers, and Lundberg and Rose (2000) demonstrate that it is not because men with higher earning capacities are more likely to become fathers that fathers earn more than non-fathers. It is motherhood itself that reduces wages, and it is fatherhood itself that increases them.

Further, Lundberg and Rose (2002) find, once again using the fixed-effect model, that such ‘wage reward’ for fatherhood is greater if the men have boys than if they have girls. Men earn more, and work longer hours, in response to the birth of sons than to that of daughters. What accounts for these peculiar patterns? What explains the puzzling fact that motherhood carries a wage penalty but fatherhood carries a wage reward, and that such wage reward for fatherhood is greater if the men have sons than if they have daughters?

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Precautionary principle : An Evolutionary Perspective

In his 2010 paper, “Why Liberals and Atheists Are More Intelligent”, Kanazawa stated :

When our ancestors faced some ambiguous situation, such as rustling noises nearby at night or a large fruit falling from a tree branch and hitting them on the head, they could attribute it either to impersonal, inanimate, unintentional forces (wind blowing gently to make the rustling noises among the bushes and leaves, a mature fruit falling by its own weight from the branch by the force of gravity and hitting them on the head purely by accident) or to personal, animate, intentional forces (a predator sneaking up on them to attack, an enemy hiding in the tree branches and throwing fruits at their head).

Given that the situation is inherently ambiguous, our ancestors could have made one of two errors of inference. They could have attributed the events to intentional forces when they are in fact caused by unintentional forces (false-positive or Type I error) or they could have attributed them to unintentional forces when they were in fact caused by intentional forces (false-negative or Type II error). The consequences of Type I errors were that our ancestors became unnecessarily paranoid and looked for predators and enemies where there were none. The consequences of Type II errors were that our ancestors were attacked and killed by predators or enemies when they least suspected an attack. The consequences of committing Type II errors are far more detrimental to survival and reproduction than the consequences of committing Type I errors. Evolution should therefore favor psychological mechanisms which predispose their carriers to commit Type I errors but avoid Type II errors, and thus overinfer (rather than underinfer) intentions and agency behind potentially harmless phenomena caused by inanimate objects. Evolutionarily speaking, it is good to be paranoid, because it might save your life (Haselton and Nettle 2006).

Recent evolutionary psychological theories therefore suggest that evolutionary origin of religious beliefs in supernatural forces may stem from such an innate bias to commit Type I errors rather than Type II errors. The human brain may be biased to perceive intentional forces (the hands of God at work) behind a wide range of natural physical phenomena whose exact causes are unknown. If these theories are correct, then it means that religion and religiosity have an evolutionary origin. It is evolutionarily familiar and natural to believe in God, and evolutionarily novel not to be religious.

Then, if the precautionary principle, so often despised by economists, is evolutionarily familiar, it appears that this attitude is highly beneficial because this will improve our reproductive success. As such, ideology like liberalism is maladaptative; by promoting unnatural attitude, it tends to decrease our reproductive success, unless the relation has been distorted by government’s laws (an example of this is provided by Kanazawa & Savage, 2009, p. 122). This is why liberalism correlates with higher IQ, and this is why high IQ is detrimental. Not surprising if the so-called “racism” correlates with low IQ. Given the precautionary principle, it is natural to distrust strangers. Again, this is because the consequence of Type II errors (thinking that the danger is not there when it is) does not worth the risk.

Why Nobody Seems to Know What Exactly Social Capital is

Why Nobody Seems to Know What Exactly Social Capital is

Satoshi Kanazawa & Joanne Savage, 2009, Journal of Social, Evolutionary, and Cultural Psychology.

Abstract: There is no consensus on what social capital is because there is no widely accepted theory of values. Capital is a resource that helps individuals achieve some goal, so one needs to know what humans seek to achieve before one can define what capital is (social or otherwise). Evolutionary psychology is a strong contender for a general theory of values. From this perspective, social capital is any resource that inheres in relationships between individuals that help them attain reproductive success. An evolutionary psychological perspective on social capital can solve some empirical puzzles: Why women have more kin in their personal networks than men do; why black women are more likely to have children out of wedlock; why social capital often has opposite effects on status attainment of men and women; and why social capital appears to be declining in the US. An evolutionary psychological perspective can tell us what exactly social capital is, why humans are social and social capital is important to them, when and where humans maintain social relationships, and how to measure social capital precisely.

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‘First, Kill All the Economists. . .’

“First, Kill All the Economists…”: The Insufficiency of Microeconomics and the Need for Evolutionary Psychology in the Study of Management

Satoshi Kanazawa

Manage. Decis. Econ. 27: 95–101 (2006)

Haselton and Buss’ (2000; Haselton, 2003) error management theory can tell us why. Their theory begins with an observation, made earlier by others (Yamagishi et al., 1999), that decision-making under uncertainty often results in erroneous inferences, but some errors are more costly in their consequences than others. Natural and sexual selection should then favor the evolution of inference systems that minimize the total cost of errors, rather than their total number. For instance, if a man must infer the sexual interest of a woman whom he encounters, he can make two types of errors: He can infer that she is sexually interested when she is not (false positive or Type I error), or he can infer that she is not sexually interested when she is (false negative or Type II error). What are the consequences of each type of errors?

The consequence of a Type I error, thinking that she is interested when she is not, is that he would be turned down, maybe laughed at, possibly slapped in the face. The consequence of a Type II error, thinking that she is not interested when she is, is a missed opportunity for copulation and to increase his reproductive success. The latter cost is far greater than the former. Thus men should be selected to possess a cognitive bias which leads them constantly to overinfer women’s sexual interest.

Haselton and Buss’ error management theory not only explains previously-known phenomena, such as a laboratory experiment demonstrating that men, both as participants and observers, overinfer women’s sexual interest than women do (Abbey, 1982), or the Safeway fiasco, but also leads to two novel predictions. First, women should underinfer men’s romantic commitment to them, because the cost of a Type I error (thinking that a man is romantically committed to her when he is not, getting pregnant by him, then having him desert, and having to raise the child alone) is far greater than the cost of a Type II error (thinking that he is not romantically committed to her when he is, and missing an opportunity to form a committed romantic relationship with him). Second, men’s tendency to overinfer women’s sexual interest should not apply to their sisters, because men need to perceive their sisters’ sexual interest in men accurately, so that they can protect the sisters in case they encounter unwelcome sexual advances from men.