Like other timeless stories, I see this story as having multiple layers of truth such that different generations can find meaning that resonates with their knowledge and experience. Here are my thoughts, taken from a section of my book Guided by the Faith of Christ: Seeking to Stop Violence and Scapegoating (nearing completion):
The Tree of Knowledge of Good and Evil
Why was the tree of the knowledge of good and evil forbidden? This question has prompted much theological reflection. I will offer some thoughts drawn from the social sciences, keeping in mind that I regard the Garden of Eden story as a parable and not as a historical account.
Evolutionary theory presumes continuity between species, and consequently one would not expect there to be any uniquely human attributes. However, certain attributes might be distinctly developed in humans. As humans evolved from prehuman creatures into humans, our remote ancestors came to experience more anger, bitterness, and resentment when they lost competitions for objects of desire. Whereas the desires of prehuman creatures were likely more ephemeral and material, such as immediate satisfaction of hunger or sexual cravings, human desires tend to be more persistent and symbolic, such as gaining self-esteem or a sense of meaning.
As a parable of humanity's origins, I think the Garden of Eden story describes the emergence of what we might call human self-consciousness. While many animals demonstrate self-consciousness the Garden of Eden story explores the consequences of experiencing human self-consciousness.
Human self-consciousness involves the ability to recognize that one is a living being distinct from others. We can imagine how others perceive us, and we can empathetically imagine how we would feel if we experienced what others experience. This ability to see things from other perspectives allows us to envision different possibilities emanating from a given situation. Therefore, to the degree that prehumans lacked this kind of self-consciousness, they likely were unable to perceive evil, because recognizing evil requires an ability to recognize that other, better possibilities could arise from a given situation. Prehumans surely experienced suffering and fear, but most likely they had little capacity to view these experiences as "evil." Prehumans tried to avoid pain and death, but they did not seek to understand why the world included pain and death, because they could not imagine other possible realities. Without these cognitive skills, prehumans generally experienced the world as resembling the biblical Garden of Eden. They usually had enough to eat, they were not pre-occupied with worries about possible future food shortages, and they were not distressed about the prospect of their inevitable demise.
Gaining human self-consciousness, humans saw themselves as actors in a world in which they might suffer or be killed at any time, and they would definitely die. This describes the effect of eating from the tree of knowledge of good and evil: Knowing good and evil, humans could no longer relate to God and God's creation in harmonious balance. Fearing possible suffering and death, humans came to see the world as full of danger, competition, and strife, even in the absence of immediate dangers or challenges.
Consequently, in times of plentiful food and other resources, people have tended to hoard as a hedge against possible scarcity, often generating actual scarcity. With scarcity, conflicts have arisen that have often led to violence. One thing that has kept people from hoarding excessively has been the fear of being killed by the victims of their rapaciousness. Since fear of death has been one of the few things that has tempered acquisitiveness, God rightly feared what would happen if Adam and Eve gained immortality by eating of the tree of life. The only way to save Eden from total destruction was for God to banish Adam and Eve. Therefore, the human desire to distinguish good from evil, a consequence of human self-consciousness and abstract thinking abilities, has made it impossible for humans to experience nature as the mythical Garden of Eden.
It is noteworthy that, after eating the forbidden fruit, "The eyes of both were opened" (Genesis 3:7), which I regard as metaphorically describing their gaining human self-consciousness. With self-consciousness, Adam and Eve could regard themselves as a third person might regard them, and from this perspective they saw their sexual and other desires as shameful. In contrast, previously they were unabashedly naked and "one flesh" (Genesis 2:24). After eating the forbidden fruit, they recognized their nakedness and covered themselves with sewn fig leafs. In other words, human self-consciousness generates the capacity to feel guilt and shame, and guilt and shame are unpleasant feelings that people are eager to transfer onto other individuals. Consequently, Adam blamed Eve and Eve blamed the serpent for their transgression.
Our self-consciousness allows us to imagine how God views us; and our shortcomings, including our illicit desires, make us feel vulnerable to divine condemnation. Therefore, accompanying human self-consciousness is a strong inclination to transfer our sense of guilt and shame onto other individuals, i.e., to scapegoat.
8. Whatever animals were like before the time when humans gained self-consciousness, scientific investigations - primarily studies of animals in their natural habitats - have found that many animals today exhibit evidence of thoughts, feelings, and self-consciousness. See Bekoff, Marc. 2006. Animal Passions and Beastly Virtues. Philadelphia: Temple University Press; and Masson, Jeffrey Moussaieff. 1995. When Elephants Weep: The Emotional Lives of Animals. New York: Delacorte; Midgley, Mary. "Persons and Non-Persons," in Singer, Peter, ed. 1985. In Defense of Animals. New York: Basil Blackwell, pp. 52-62.
9. There is scientific evidence of empathy in some more cognitively skilled animals. This not only illustrates moral character among animals but also suggests an important degree of abstract thinking ability. In one study, rhesus monkeys, upon pulling one of two chains to get food, observed through a one-way mirror a second rhesus monkey receiving a simultaneous electric shock. One chain caused a fellow monkey to receive an electric shock, and the other did not. Ten of fifteen monkeys preferred the non-shock chain, and two monkeys did not pull either chain, preferring instead to go without food for 5 days and 12 days. Self-starvation was more likely among monkeys who had previously received electric shocks themselves. (See Masserman, Jules H., Stanley Wechkin, and William Terris. 1964. " 'Altruistic' behavior in rhesus monkeys." American Journal of Psychiatry vol. 121, pp. 584-585.) The documentary People of the Forest depicts an adult male chimpanzee who watched over and protected an unrelated, crippled, adolescent chimpanzee from the torment of other adolescent chimpanzees. (See Van Lawick, Hugo, director. 1991. People of the Forest, Discovery Channel Video.)