To understand Robert Wright, it is first necessary to define evolutionary psychology, which is the foundation of Wright's theory. Evolutionary psychology contends that most, if not all, of human behavior can be understood by the interests of internal psychological mechanisms. These internal mechanisms are adaptations, or products of natural selection that helped human ancestors survive and reproduce. Evolutionary psychology looks at the challenges early humans faced in their hunter-gatherer environments and the problem-solving they went through to meet those challenges. Based on these problem-solving adaptations, it then establishes the common roots of ancestral behavior and, especially related to Wright's book, how these common behavioral roots are observed and acted upon today. Human behavior, just like physical traits, has passed on from generation to the next. In their brains humans have specific knowledge that helps them adapt to the environment. The brain is subject to natural selection just like any other organ.
As Wright explains in the introduction (9), evolutionary psychologists discern the second level of human nature: Anthropologists find recurring themes in cultures, such as a need for social approval and capacity for guilt. Psychologists explain that these themes alter from person to person, where one person's desire for social approval is low and another person's high. Genetic differences play a role, but more so, genetic commonalities play a bigger role. There is a species-wide developmental program that absorbs information from the social environment, and the brain adjusts correctly to it.
Wright thus explains that humans are genetically created by evolution to replicate their genes. There is a biologically-based human nature where all organs in the body are "adaptations" or "fine products of inadvertent design" (26), which exist today because in the past they contributed to an ancestor's fitness. All these organs, as noted above, are species typical. There may be differences, but on the whole, most of the genes from one organ, such as the lung, are the same as another person's.
Darwin summed up natural selection as "Multiply, vary, let the strongest live and the weakest die" (24). Here, according to Wright, "strongest" does not only refer to the brawniest, but also to other ways of adapting the environment, such as camouflage, and, in the case of this book, cleverness and other mental adaptations. The word "fitness" is the task of transmitting genes from generation to generation within a specific environment. Fitness is the factor that natural selection continually "seeks" to maximize and improve, as it continuously redesigns the species. Fitness is what made humans act as they do today. The human body was made by hundreds of thousands of incremental advances, with each increment being the result of an accident that helped one ancestor to get its genes into the next generation.
Wright then extends this concept to the brain and today's modern mind. Why, he asks, should the organ of the brain be any different from these other organs? Mental organs, which make up the mind, are species typical as well. The hundreds of thousands genes that affect human behavior -- genes that created the brain and control neurotransmitters and other hormones -- have continued to exist from the early ancestors to present time for a reason. That reason is that they goad humans to extend their genes from one generation to the next. Assuming the theory of natural selection is correct, then everything about the human mind should be understood in these terms. The fundamental way that people feel about each other, the basic things individuals think about each other and express to one another, are all part of the makeup of the mind because they were able to pass on genetic fitness.
Male and Female.
Wright explains that differences exist between males and females and their ultimate goals to achieve this state of fitness. To determine what females are inclined to seek in males and males in females, it is necessary to refer back to the ancestral environment. It is important to remember that the behavior observed today is not based on the present environment, but the one that existed thousands of years ago to which early humans adapted. This ancestral environment provides an understanding why females are less sexually reserved than females in any other species and why the reserve for females in the human species is higher than the level for males, regardless of the environment. This is based on the premise that over her lifetime, an individual female is able to have many fewer offspring than an individual male. Such reproduction exists much farther back in time than with early humans; it stems back through evolution to the reptiles. For example, female snakes only mate with certain males. Thus, females are inherently coy or "precious" because of their biological role in reproduction, and the slow rate of female reproduction.
This choosiness by females is based on natural selection, because it "gives great moment to their choices," as noted by Darwin (34). If females prefer to mate with a particular kind of male, those kinds will proliferate. Such ornamentation of male animals, such as the lizard's inflatable throat sack, has evolved not because it helps in daily survival, but because it can charm the female and, in the case of a stag's horns, can win at combat. Both these traits, ornamentation and combat, are part of sexual selection.
Natural selection unconsciously ingrained in organisms both certain physical and mental traits to maximize genetic legacy. This goal implies different tendencies for males and females.
Males can reproduce hundreds of times a year, but females can only reproduce once a year. For men, doing better is to have more partners and get more genes into the next generation.
However, for women, the answer is quality, not quantity. Having a child involves a great deal of time and effort. Each child, because of genetic reproduction, is very precious. Parental investment includes producing the egg or sperm, achieving fertilization, gestating the egg, and rearing the offspring. Females make the higher investment both up until birth and, in most cases, after birth as well. The child must survive and pass on its genes to the next generation. Women, therefore, must be very selective about the men they choose to create these children. Unconsciously, based on thousands of years of history, a woman "sizes up" a man and is attracted or not attracted based on natural selection. Genes leading to attractions that ended up good for genetic legacies have flourished, and those leading to less productive attractions did not. People's minds are designed to maximize fitness in the environment when those minds evolved. Only the traits that propelled genes from one generation to the next should, in theory, be part of today's human nature. These stem from the environment of the hunter-gathers.
As noted by Trivers, (42), quantifying the imbalance of investment between mother and father helps to better understand many things, such as the dichotomy between male eagerness and female coyness, the intensity of sexual selection, subtle aspects of courtship and parenthood, male-female bonding and fidelity and infidelity. Rightly so, as Trivers suggested, such behavior results from a psychological complexity. The basic emanations of natural selection come from the older parts of the brain all the way into the newest tissue.
Men and Women
It is very easy, then to see why men developed in a way to help rear their young. Genetic factors made it worthwhile for a man to love his offspring, to worry about them, defend them, provide for them, and educate them. This helped the children survive and pass on their genetic heritage. If an offspring did not live long enough to reproduce, then there was no need to produce the offspring in the first place. This is why most species were monogamous: to help the mother protect the offspring against predators. Men needed to hunt to feed his family. Somehow this developed into the sensation of love, not only for the child but for the man and woman. The genetic value of having two parents devoted to each other and their children was great.
For hundreds of thousands of years, natural selection has been inclining males to love their children. During this same time, natural selection had been favoring men and women to love each other. The lifestyle of today's philandering bachelor in large populated cities, who seduces and abandons available women time after time for years without any parental investment, has not been a wise sexual strategy in the past when women were married as soon as they became fertile. A woman's genes would be well served by her early and critical scrutiny of a man's likely devotion. Women have wanted men who are ambitious, generous, trustworthy and, most important, especially committed to her. This then became part of the female psychology.
At the same time, just as women have a reason to focus on a man's ability to provide resources, men have a particular reason to focus on producing babies. They have to care about the…