This blog post examines whether human character and intelligence are determined at birth or shaped by environment and upbringing, using various examples.
Most people have heard of the theories of innate goodness and innate evil. This question of whether human nature is inherently good or evil has been a significant topic in both Eastern and Western philosophy. The doctrine of innate goodness posits that humans are born with a fundamentally good nature, which can be further developed through proper education. Mencius is a prominent proponent of this view, arguing that humans are born with an innate capacity for altruism. Conversely, the doctrine of innate evil posits that humans are born with an inherently selfish and wicked nature, which must be reformed through social discipline and moral training. Xunzi, representing this view, believed humans possess selfish desires from birth and can only develop into desirable individuals through education and training.
Although these theories appear contradictory, they share a crucial commonality: They both acknowledge that even if human nature is innate, its expression can be shaped by subsequent effort and environment. Both the theory of innate goodness and the theory of innate evil emphasize that humans must exercise self-control and make efforts to live virtuously or morally correctly. So, is human character truly determined not by innate nature, but by subsequent environment and upbringing? To explore this further, let’s examine two socially prominent examples.
In 2004, a man named Yoo Young-chul caused a major uproar in South Korea by committing a series of murders. He brutally killed over 20 innocent people and was diagnosed as a ‘psychopath’ with antisocial personality disorder during the investigation. Psychopaths typically lack a sense of moral ethics or guilt. They exhibit a deficiency in emotional bonds within relationships, displaying cold and selfish tendencies. As news of Yoo Young-chul’s case spread, Korean society became deeply interested in antisocial personality disorders like psychopathy and sociopathy. Among the public, unverified psychopathy tests of unknown origin also proliferated.
Generally, people believe antisocial personality disorders like psychopathy or sociopathy are innate, influenced by genetic factors. Indeed, many criminal psychologists view antisocial personality disorder as emerging in childhood and persisting into adulthood as a stable trait. This is because children exhibiting antisocial tendencies often show an inability to understand moral standards or feel guilt from a young age. However, some studies suggest that these tendencies can be significantly influenced not only by genetics but also by acquired factors like the upbringing environment. In other words, even if nature is innate, environment and upbringing can play a crucial role.
Another example often cited to illustrate this is the movie Kevin. Released in 2011, the film is based on the novel of the same name. The story centers on the relationship between Kevin and his mother, Eva. From a young age, Kevin displays resentment toward his mother, deliberately engaging in behavior meant to torment her. He ignores her when she calls him, or repeatedly says “I don’t want to” to deliberately disregard her. Growing up, Kevin exhibits abnormal behavior. He kills his younger brother’s hamster and injures his brother by putting dish soap in his eyes, yet feels no guilt. Ultimately, just before turning 16, Kevin murders his father and brother and attacks his schoolmates in a large-scale incident.
The cover of the Korean translation refers to Kevin as a sociopath. So was Kevin destined to be a criminal from birth? To find the answer, we must examine the behavior of his mother, Eva. From the moment Kevin was born, Eva treated him indifferently, holding him as if she were merely carrying him rather than embracing him. She even stood next to a construction site to deliberately amplify the noise, silencing Kevin’s cries.
Crucially, Eva utters the words, “I would have been happier without you.” These actions suggest Kevin’s abnormal tendencies were not solely innate but also influenced by environmental factors.
Meanwhile, intelligence is widely recognized as one human trait significantly shaped by environment and upbringing. Studies on intelligence show that it can be influenced by environmental factors as well as genetic ones. According to Richard Nisbett’s book Intelligence, IQ tests were originally developed to predict academic achievement but later became established as a method for measuring intelligence. Nisbett explains that while IQ is partly determined by genetic factors, environmental factors also exert a significant influence.
For example, studies measuring IQ in children during early childhood and again years later indicate that IQ can vary not only due to genetic factors but also based on educational environment, parental attention, and family economic support. Notably, children tend to have higher IQs when class sizes are smaller and teacher quality is higher. This serves as a clear example of how education and environment influence intelligence.
Synthesizing these examples leads to the conclusion that human traits like personality or intelligence are not solely determined by innate nature but are highly susceptible to change through the influence of acquired environments and upbringing. However, human characteristics extend far beyond antisocial personality disorder or intelligence. Research is still needed to determine the extent to which specific traits are influenced by the environment.
Thus, humans are exposed to their environment from birth and live under its diverse influences. The question of whether nature or nurture is more important may remain difficult to answer definitively. Nevertheless, the value of such research lies in its potential contribution to exploring better parenting methods and educational approaches.
