Who I am? What is it that affect my actions? Am I doing what I really want to do or is there an invisible force internal or external driving my actions and fooling me to think that it is me who is the captain of my life? Sometimes under the influence of extreme anger, we think and ask ourselves ‘that was not me’, ‘I was out of character’. These are a few questions regarding the development of our personality and the old age bifurcation of nature vs. nurture. These questions are very important questions to ask and every human being ask himself or herself these questions in the course of their lives. There are no straight answers to these questions and the debate is ancient in human intellectual history that date back to the ancient Greeks, thinkers the like of Plato and Aristotle and hence, the debate is still here puzzling and amazing us with its complex implications and repercussions that does not provide a simple answer but forces us to ask more questions that in turn leads to further questions. This chain of questions and no specific answers do not mean that the debate is a waste of time but on the contrary it introduces to the more insightful, deeper and uncanny nature of human existence and the world we live in.
Therefore, the purpose of this essay is not to give you the hard fast rules about the development of human personality but to introduce the reader to this ongoing debate that does not cease to amaze us due to the open-endedness and ambiguous nature of this debate. In the course of this essay, first, we would examine the gene-environment interaction influence on human personality and the cultural factors that influence personality development. Similarly, we would also examine the twin studies and its influence on inheritability on human personality. Furthermore, we would also see the features of temperament regarding its contribution to adult personality and its constancy and variability over time.
The most important thing regarding the knowledge of the personality development as I have already referred in my introduction about the two sides such as nature and nurture, the gene-environment interaction emphasizes that both genes and environment contributes in the development of our personalities. Second, genetic and environmental influences are not independent, the effect of one variable depends on the other. For example, human beings have the natural tendency to kill their fellow beings but this natural instinct does depend on external factors and more specifically the stimuli that are provided through environment. Hence, their dependency is the crucial concept to understand gene-environment interaction studies in personality development.
This interaction between genes and environment is commonsensical. For example in Joseph Conrad’s Heart of Darkness there is a sequence where an Englishman kills a Congolese merely for the reason of telling him the wrong price of the hen and according to Conrad that man was regarded as ‘the most gentlest and kindest man ever walked on earth’. Hence, our environment controls our genes, hence, ‘in essence, it is only when adverse environmental conditions are experienced that the genes come on-line’ (Dick and D.M, 2011). A recent study has also introduced a new term known as ‘plasticity genes’, according to this idea the genes which are negatively affected by the adverse environments are likely to advantage more from the positive environment (Belsky J et al., 2009).
Twin studies are the most important of all in order to investigate the insights into the nature versus nurture argument. As far as the twin studies are concerned regarding the inheritability of personality results shows variations. According to this study the environment plays an important role in controlling the genes. For example, the individual who have low genotype on extraversion would be low on extraversion if predisposed to an environment very organized and suppressive while on the contrary the individuals who have high score on extraversion trait would score high regardless of their environment. In the second case, the individual who have genotype of high impulsivity trait would increase this impulsivity if predisposed in a conflict filled environment (Bergeman et al, 1988).
Temperament is defined as the emotional reaction that one shows towards his/her environment. It is very difficult to answer this question by referring to the simple categorization of the things that stay stable and the things that change over time, nevertheless, some temperaments which stay stable over time would contribute to personality development to adults. For example, introverts are to stay introverts for the rest of their lives while in some cases the introverts seem to get out of this psychological condition. Although some people argue that the brains of the introverts are wired the way they cannot bear the burden of sociability and hence are forced to isolation, friendliness and emotional anxiety. Similarly, there are many psychological issues involve in the development of our temperament in our early childhood that is also known as Freudian subconscious. These childhood traumas develop one’s temperament which is life long and unchangeable in the case many individuals, sometimes it is positive and productive for individuals (artists) and the other times it can be fatal and painful (cases related to sexual abuse and child molestation).
Culture plays and important role in the development of our personalities, culture programs our minds, our minds are easily manipulative and can be controlled accordingly. I gave an example of the character from Conrad’s novel. What was that things that resisted him to behave nicely in England while mercilessly in Congo? I think the answer is the culture that consist of values, law, and most of all the law enforcement institutions, the moment you have removed these institutions that inflict or try to inflict order, you are exposed to your real nature, the nature of an ape who can kill if opened into the wilderness of Africa. The Lord of the flies is another beautiful work of art that deals with this issue of cultural and institutional programming in human societies.
The brief summaries that I have provided so far is a small attempt to understand human nature and it’s working in the environment he/she lives in. the studies we have discussed give no black and white answer to the posed questions of what contributes in the development of human behavior and human personality. For some cases, genes seem to rule our behavior while in other cases it the environment, while in other cases it is both environment and genes that stimulates human behavior. Hence, there will never be any study that can give a closed ended answer to the mysteries of human personality and its make but the chunks of studies that rationalize it on case by case basis.
Belsky, J., Jonassaint, C., Pluess, M., Stanton, M., Brummett, B., & Williams, R. (2009). Vulnerability genes or plasticity genes?. Molecular psychiatry, 14(8), 746.
Bergeman CS, Plomin R, McClearn GE, Pedersen NL, Friberg LT
Cervone, D., & Pervin, L. A. (2015). Personality, binder ready version: theory and research. John Wiley & Sons.
Dick, D. M. (2011). Gene-environment interaction in psychological traits and disorders. Annual review of clinical psychology, 7, 383-409.
Psychol Aging. 1988 Dec; 3(4):399-406.