In this blog post, we will look at whether human personalities and intelligence are determined by nature or formed by environment and upbringing through various examples.
Everyone has heard of the theory of sexual reproduction and the theory of sexual selection at least once. This question of whether human nature is good or evil has been addressed as an important topic in both Eastern and Western philosophy. The theory of human nature states that humans are born with a good nature and that this nature can be further developed through proper education. Mencius is a representative supporter of the theory of human nature, and he argued that humans are born with a sense of altruism. On the other hand, the theory of innate evil sees human nature as inherently selfish and evil, and therefore requires social discipline and moral training to correct it. From the perspective of this theory of innate evil, Sun Tzu believed that humans have selfish desires from birth and can only grow into desirable human beings through education and training.
Although they seem to be opposing arguments, these two theories have important commonalities. The point is that even if human nature is innate, its appearance can change depending on acquired efforts and the environment. Both the theory of nature and the theory of nurture emphasize that humans must control themselves and make efforts to live a good or morally correct life. So, are human characteristics really determined by acquired environment and upbringing rather than innate nature? To understand this more deeply, let’s look at two examples that have received social attention.
In 2004, a man named Yu Young-cheol caused a stir in South Korea with a series of murders. He was a serial killer who brutally murdered more than 20 innocent people, and as a result of the investigation, he was diagnosed with antisocial personality disorder and was deemed a “psychopath.” Psychopaths are generally characterized by a lack of moral ethics or guilt. They lack emotional bonds in human relationships and show cold and selfish tendencies. As the case of Yu Young-cheol became known to the world, Korean society became very interested in antisocial personality disorders such as psychopathy and sociopathy, and unidentified sources of psychopathy tests spread among the public.
Generally, people think that antisocial personality disorders such as psychopathy and sociopathy are inherited by genetic factors. In fact, many criminal psychologists believe that antisocial personality disorders appear from childhood and are not easily changed even as adults. This is because children with antisocial tendencies tend not to understand moral standards or feel guilty from a young age. However, some studies suggest that this tendency may be influenced not only by heredity but also by acquired factors such as the upbringing environment. In other words, even if nature is innate, the environment and upbringing can play an important role.
Another example often cited to explain this is the movie “Kevin’s Story.” The movie was released in 2011 and is based on a novel of the same name. The movie revolves around the relationship between Kevin and his mother, Eva. Kevin has had a dislike for his mother since he was a child and deliberately acts to annoy her. He ignores his mother by not answering when she calls or deliberately repeating the word “no.” Kevin, who showed abnormal behavior even as a child, kills his brother’s hamster, puts dish soap in his brother’s eye and hurts him, and commits other dangerous acts, but does not feel guilty. Eventually, Kevin murders his father and brother shortly before turning 16 and causes a major incident in which he attacks his classmates.
The cover of the Korean translation says that Kevin is a sociopath. So was Kevin destined to be a criminal from birth? To find the answer, we need to look at the actions of Kevin’s mother, Eva. Eva treated Kevin indifferently from the time he was born, holding him as if she were holding him up, and standing next to a construction site to intentionally make the noise louder to block Kevin’s crying. Crucially, Eva tells Kevin, “I would have been happier without you.” These behaviors suggest that Kevin’s abnormal tendencies may have been influenced not only by his innate characteristics but also by acquired influences.
On the other hand, intelligence is widely recognized as a human trait that is greatly influenced by the environment and upbringing. Studies on intelligence show that intelligence can be changed by environmental factors in addition to genetic factors. According to Richard Nisbett’s book Intelligence, IQ tests were originally developed to predict academic achievement, but have since become a way to measure intelligence. Nisbett explains that while IQ is partly determined by genetic factors, environmental factors also have a significant impact.
For example, a study that measured IQ in children several years after they had been tested as infants found that IQ can vary depending on not only genetic factors but also the educational environment, parental attention, and financial support at home. In particular, the smaller the class size and the higher the quality of the teacher, the higher the IQ of the children tended to be. This is a good example of the impact of education and environment on intelligence.
When we put the above cases together, we can conclude that traits such as personality and intelligence are not simply determined by innate nature, but are highly likely to change under the influence of acquired environment and upbringing. However, there are many other traits of human beings besides antisocial personality disorder and intelligence. Research is still needed to determine how much a trait is influenced by the environment.
As such, humans are exposed to the environment from birth and live under various influences. It may still be difficult to find a clear answer as to whether nature or upbringing is more important. However, such studies are of great value in that they can contribute to the search for better parenting and educational methods.
