On Nature Versus Nature

On Nature Versus Nurture

The “Nature Versus Nurture” debate has raged on for centuries, and is still relevant today as it is concerned with our intelligence, personality and physique, and our understanding of the human race in its entirety. Its goal is to determine which is more important in the adult human; Nature (our innate being, the genes descended from our ancestors) or Nurture (personal experience, whether it be environmental, cultural or familial).
In the mid 19th century, the first published work on this matter was produced by Sir Francis Galton, entitled “Hereditary Genius: Its Laws and Consequences”. Galton was fascinated with the idea that talented individuals often came from families with similar abilities, and observed that it would be possible to produce “super-humans”, which would be extraordinarily talented, and essentially speed up the process of natural selection through human-selective breeding (This would later become known as Eugenics, and was a field of particular interest to Adolf Hitler and the Nazi party). This idea (much like Nietzsche’s “super-man”) was commonly abused and misinterpreted to fit the ideas of many racist and apartheid schemes, and to withhold human rights from certain races.
By the early 20th century, views worldwide were much less extreme, and analysis of intelligence test data suggested that it was social class, and not race, which affected the average Intelligence Quotient. This made many psychologists believe that although genetics still had an impact upon humans, their childhood and socio-economic success was the key in determining their overall intelligence and personality.
Despite much progress in this turbulent field, there are still large amounts of disagreement and hostility between different scientists, philosophers, psychologists and religious groups. Determining the heritability of certain traits and intelligence quotients is extremely difficult, and so the most obvious way of analysing the differences of experience is through separating identical twins (as both have the same genetic makeup), and studying their different lives and personalities years later, though this has obvious moral implications.
The results from tests such as these do seem to suggest that identical twins reared apart show much more similarity than two randomly selected people, and this evidence has been used in support of the “nature” argument. Also, biological siblings show much more personality similarities than adoptive siblings, despite them having the same environment to grow up in. These results show that personality is heritable to a certain extent, though gives no definitive answers.
Some sceptics are unconvinced however of the results showing anything, as they have pointed out that the environment that the children are brought up in can influence the ways that their genes manifest and develop. This occurs because of Epigenetic Markers, which adjust the intensity of the gene manifestation. Twins are born with the same epigenome, but as environmental factors affect them more they grow older, these can be altered and it is the key reason why twins become less alike as they grow older. This has puzzled scientists even more so, as it could mean that although people may not have a disorder, it could still be genetic. Taking this into account, it becomes extremely hazy as to which (Nature or Nurture) has contributed more to the development of the twins.
The idea that experience shapes our genes is supported by a recent study that began fifteen years ago, when scientists gave 30 babies a selected diet, 15 of which were given high-protein food, and the other half were prescribed the regular recommended diet. The babies who were given the high-protein diet came out significantly higher in an IQ test done fifteen years later than the babies with the normal diet. This evidence suggests that intelligence (as far as humans can measure it) can be improved as well as knowledge over the course of a life.
Another commonly known (although very rarely supported) argument is the “Tabula Rasa” opinion, which states that all children are blank slates which have all their ideas, personality, physique and moral basis etc given to them through experience of one kind or another, and this opinion fails to take genetics into account. This is quite an outdated opinion, yet still one which some take seriously. It is however, an important view, as it is firmly based at one end of the spectrum, and so gives hypothetical ideas that allow one to grasp the different viewpoints of the entire debate.
For instance, if all of us were only affected by experience, which experience is of utmost importance? Is the culture we live in the central factor, or are the people we know and how they act? Such questions can never be definitively be answered, but asking them and thinking about them is the only way we can truly grasp what experience is, and understand this side of the argument. A famous quote (of the Tabula Rasa opinion) from the psychologist John B. Watson in 1924 stated that given twelve healthy young infants and his own specific world, he could take any one at random and train them to become any type of specialist he chose, regardless of their talents, tendencies, penchants, abilities and race of their ancestors.
A recent work in this debate, which strongly contrasts from the Tabula Rasa opinion, is “The Bell Curve” written by Herrnstein & Murray in 1994, which caused a huge amount of controversy in the debate, as it was firmly placed in the “Nature” side of the argument. The book was called “alien and repellent” by some and named the authors as “pseudo-scientific racists”. According to the Herrnstein & Murray, Asians and Asian-Americans have a superior IQ to that of White Americans, and that the latter have a higher IQ than Africans and African-Americans. It also states that the lower socio-economic success does not cause low intelligence, but that low intelligence causes lower socio-economic success. This view was met with much hostility, but despite this, even those who opposed the book recognised that it was an important work, which contributed to the psychological and social side of the “Nature Vs. Nurture” debate. The book’s main hypothesis is that intelligence is heritable and because of this, certain races are superior in intellect to others.
Aside from the many scientific and psychological studies that have taken place in order to try to find a clear-cut answer, many theologians and philosophers have also taken a keen interest in this debate, as it deals with free will, morals and epistemology. Free will is a concept that most believe they have, but the “Nature Vs. Nurture” debate challenges the idea deep at its core. As we have no control over our genes and the environment we are brought up in, they can shape the actions we take. Aristotle’s “Virtue Ethics” claims that the virtuous man would not do bad or evil things, as he believed that our character dictates our actions, and so if our genes and/or environment have moulded us into an evil person, we could not help but do evil actions. It is important at this point to make clear the distinction between morals and ethics; morals meaning the actions we take, and ethics referring to the character we have. The Kantian deontological morals require nothing of character, just a set of rules of which we are to follow.
If our characters (and therefore our actions) were pre-determined, could we not foresee which children could be potentially dangerous, and have them imprisoned before they have actually done anything illegal or hurtful to another human? This ‘Nineteen-Eighty Four’ approach to crime may seem heartless and somewhat disturbing, yet if we could truly determine who had criminal tendencies, would it not be logical to take such action?
Morally, the debate has always had undertones of controversy, predominantly because of the seemingly immoral ways of determining an answer to this huge question, and of the actions taken in its name. Is it morally acceptable to knowingly separate orphaned twins or siblings in order to scientifically measure their differences due to the different environments they were brought up in? Or was the high-protein diet experiment really acceptable when no one knew the outcome of feeding the babies the unnatural diet scheme. Fortunately, the high-protein was beneficial for the babies, but if it had not been, how could it have been justified when the babies had no say in their participation?
Eugenics is a subject that has never been far away from the topic of “Nature Vs. Nurture”, as it the study of improving the human species through human selection, rather than the evolutionary natural selection. Such a process is fraught with moral complications, and has caused a great deal of hurt. The holocaust is a key example of Eugenics in practice, the Nazis systematically wanting to rid Germany and the world of numerous races such as the Jews, the Slavs and the Blacks in order to make way for an Aryan only super-species.
The debate also throws into question the subject of epistemology, and how we come to have the ideas and knowledge we have, whether it be from our genes, our experience of the world, or as some believe, from a God. For instance, in a western society such as the United Kingdom, the majority of the population agree with the judicial system and the laws it sets down. Do they agree with this because they have experienced what is “good” and “bad”, or they know others who have experienced such events? Or, do they agree because most people are inherently “good” (either because of a God or because of genes and innate qualities) and have a firm idea of what is right and wrong?
The search for the answer in the “Nature vs. Nurture” debate is fruitless, as the terms ‘nature’ and ‘nurture’ are joined in every respect, for the experiences (the nurture) of our ancestors have (through evolution) shaped the human beings we are today (our nature). Other recent experiences, such as if a mother smokes before pregnancy and it affects her child, mean that one person’s experience will directly alter another’s nature. A famous psychologist once answered in reply to the “Nature Vs. Nurture” question, ‘What is more important in the area of a triangle, its height or its width?’. I have the belief that a question such as ‘what is more important, nature or nurture?’ is unanswerable, as both are intrinsically linked and are mutually dependent on one another. Both are equally important in shaping our qualities, traits, intelligence and physique, and so neither can be said to have more importance than the other.

By Matthew Short

This is a paper I wrote a couple of months back now, and this is a subject I've become keenly interested in. I'd love to hear some listologists' views and opinions on the subject of Nature Vs. Nurture.