In this blog post, we will examine whether personality is determined by genetic factors or shaped by our environment and relationships.
There has been a long-standing debate about whether nature (innate characteristics) or nurture (acquired characteristics) plays a more important role in shaping a person’s personality. To clarify this, experiments have been conducted, such as raising identical twins in different environments or raising different children in the same environment. However, due to methodological and ethical limitations, these experiments have not been able to draw clear conclusions about what is important. In this article, we will show that acquired characteristics have a greater influence on the formation of human personality than innate characteristics through the concepts of reductionism and relationalism.
Reductionism and relationalism are fundamental mechanisms for analyzing any object. Historically, reductionism appeared first, followed by relationalism. First, the reductionist method refers to a method of analyzing an object or relationship by reducing it to its smallest unit. For example, when trying to understand the tendencies of a society, one can derive answers by analyzing the tendencies of each individual member, or when analyzing the characteristics of life, one can derive answers by analyzing smaller and smaller units (organs, tissues, cells, genes).
Reductionism naturally became established in people’s minds with the advancement of science and technology. Around the 17th century, a scientific revolution took place, beginning with the publication of Copernicus’s “On the Revolutions of the Celestial Spheres” and followed by Newton’s “Mathematical Principles of Natural Philosophy.” This completely changed religious thinking and led to scientific thinking being regarded as the most important element of human reason.
As research progressed in various fields, people developed a tendency to analyze all phenomena reductionistically. In physics, the discovery of molecules, atoms, protons, neutrons, and electrons was made in the pursuit of finding the smallest units of matter, which led to the development of atomic models and the rapid advancement of quantum mechanics. Furthermore, the discovery of quarks, which are smaller than protons, led scientists to attempt to analyze physical phenomena reductionistically. This was because they believed that the secrets of all physical phenomena could be unlocked by elucidating the properties of quarks and other particles that are even smaller and have yet to be discovered. In biology, research into the microscopic dimension began with the invention of the microscope by Leeuwenhoek and the discovery of microorganisms. Many studies were conducted to explain life phenomena by observing the structure of cells and even smaller units. As time passed, a historically important theory emerged: Charles Darwin’s theory of evolution, published in the mid-19th century. Darwin argued that natural selection was the key to the evolution and change of living organisms, and that genes were the most important factor in this process. When Watson and Crick discovered that these genes were actually DNA and explained how DNA passes traits on to subsequent generations, the reductionist approach to analyzing living organisms became firmly established. The double helix structure, composed of four units, was so fascinating that people believed that analyzing it would unlock all the secrets of life. The genome project, which aims to identify the roles of all units within DNA, also began in this context.
The reason reductionism emerged in this way is because scientific research was conducted at the microscopic level. This is because reductionism is an excellent method for explaining natural phenomena. When studying how visible natural phenomena occur, it is convenient to reduce them from higher-level concepts to lower-level concepts, as this facilitates understanding of detailed mechanisms. In fact, many achievements have been made using reductionist methods. Representative examples include improvements in medical technology through understanding the human metabolic process and the internal structure of the human body.
However, in the 20th century, objections to reductionist analysis methods arose. World-renowned nuclear physicist Fritjof Capra argued that “classical physics, known as mechanistic physics, was based on causality, which is the foundation of reductionism, but in modern physics, causality, which is the foundation of reductionism, does not hold true according to Heisenberg’s uncertainty principle.” Reductionism is based on causality, which states that phenomena of a higher concept can be explained by phenomena of a lower concept. However, according to Heisenberg’s uncertainty principle, it is impossible to accurately observe phenomena in the microscopic world of photons, and therefore it is impossible to identify causes, which means that causality cannot be established. Furthermore, he emphasized that the mechanistic view of nature based on reductionist causality must be replaced with an organic view of nature without unilateral causality.
The limitations of reductionism became even more apparent in the process of analyzing the complexity of living organisms. As the analysis of genes became more in-depth, it was discovered that genes are expressed to induce protein synthesis, and that these proteins in turn regulate gene expression. This led to the realization that there is no unilateral causality in the system of life. In addition, it was suggested that the uniqueness of living organisms cannot be analyzed by reductionist methods. Discussing what life is in reductionist terms means determining the characteristics of higher organisms based on the characteristics of their lower constituent units that are common to all organisms. Ultimately, the results based on this method become a grand discourse premised on the universality of all organisms, which cannot explain the uniqueness of individual organisms.
As such, there are clear limitations to explaining life and natural phenomena using reductionist methods. In particular, despite the genome project, which was a representative reductionist method for elucidating the nature of life, being almost complete, it has not been possible to explain the uniqueness of individuals through gene expression. Accordingly, a relational approach was proposed as a new method of analyzing things or objects. Relational theory is based on the premise that when analyzing an object, rather than reducing it to its sub-levels to find certain characteristics, it should be viewed as part of a larger whole, and the object itself should be viewed as a whole. In this system, the relational approach analyzes the relationships between internal structures or between the object and its external environment to identify its characteristics. This is clearly different from reductionism, which analyzes objects by breaking them down into sub-steps and then analyzing the whole based on the idea that “the whole is the sum of its parts.” Instead, it’s based on the idea that “the whole is more than the sum of its parts because of the internal and external relationships of the object.”
The concept underlying the relational methodology is that of complex systems. A complex system is a system that cannot be expressed in a single word and changes randomly due to countless variables. In such complex systems, there are macroscopic phenomena that cannot be understood by looking at individual components. There are three representative characteristics of complex systems: phase transition, scale independence, and the rich get richer and the poor get poorer. First, phase transition refers to a major change from one state to another within a complex system. In complex systems, phase transitions can occur at any time as internal relationships change. Scale independence means that a part of a complex system is another complex system, and the whole is the same as the parts, similar to a fractal. The rich get richer and the poor get poorer refers to the fact that complex systems have uneven relationships reminiscent of the rich get richer and the poor get poorer phenomenon in economics. In relational theory, since groups of living organisms have the characteristics of such complex systems, each living organism is regarded as a component of a complex system, and it is believed that the uniqueness of each individual, which cannot be understood by reductionist methods, can be understood by observing the macro-level picture.
Living organisms have a tendency to differentiate themselves from their surroundings and form relationships with their environment. The uniqueness of each individual is determined by their physical characteristics, which are conferred by their immune system, and their mental characteristics, which are conferred by their nervous system. When something foreign invades the body, the immune system removes the stimulus through an antigen-antibody reaction and records the stimulus in memory cells to prepare for the next invasion. By storing stimuli in memory cells in this way, the body gradually develops physical uniqueness that distinguishes it from the outside world. The nervous system also develops as it grows, accumulating stimuli experienced and forming behavioral patterns for each stimulus, thereby conferring mental uniqueness. When living things are first born, they are in a state of almost complete undifferentiation from their surroundings, but as they interact with their environment, they establish their individual uniqueness. For example, newborn babies have no experience and are not yet differentiated from their surroundings, so they do not know what behaviors are acceptable and what are not. However, as time passes, they learn what behaviors are acceptable and what behaviors are unacceptable through the stimuli they receive from others in response to their actions, and they form their own personalities. In other words, they differentiate themselves from their surroundings. It is important to note that most living things do not simply seek to differentiate themselves from their surroundings, but rather change the direction of their differentiation through their relationships with their surroundings. Individuals who seek to differentiate themselves alone are like cancer cells. They act solely to establish their own identity without considering the reactions of those around them. From this perspective, psychopaths, who are unable to feel the emotions of others, can be seen as people who are unable to consider their relationships with others in the process of differentiating themselves from their surroundings.
In this way, a group of individuals that grows while forming relationships with their surroundings has all the important characteristics of a complex system. First, each individual accepts external stimuli and forms relationships, creating conditions for differentiation from their surroundings and bringing about rapid change. This can be seen as a kind of enlightenment that living things gain as they differentiate from their surroundings. In other words, these changes demonstrate the potential for phase transitions in complex systems. In addition, the internal components of living organisms constantly reorganize themselves and provide mutual feedback, ultimately reconstructing themselves into better structures, which is very similar to the way countless people change in society. In other words, living organisms themselves are composed of internal structures, and they are also part of a larger society composed of living organisms. In this sense, groups of living organisms can be seen as having scale independence in complex systems. Finally, the greater the degree of differentiation of living organisms from their surroundings, the more they can differentiate themselves based on that differentiation, whereas living organisms that have not yet differentiated much must make greater efforts to differentiate themselves. This shows the uneven degree of differentiation among living organisms, which is very similar to the rich-get-richer, poor-get-poorer characteristic of complex systems.
In other words, when analyzing living things, it is difficult to grasp their essence by reducing them to lower levels and calculating the sum of each part. Rather, it is necessary to recognize the individual itself as a complex system and then analyze the internal and external relationships of the individual from a macro perspective to properly understand its essence.
Human personalities are extremely complex and difficult to understand intuitively, and each person has their own unique characteristics. In other words, as we have seen above, when it comes to complex qualities such as human personalities, it is more appropriate to apply a relational approach rather than a reductionist approach to examine their essence. Reductionist and relational analysis methods can also be interpreted as analysis methods based on innate characteristics and acquired characteristics. According to reductionism, human personality can be seen as determined by DNA information that is innate at birth. In contrast, according to relational theory, human personality is formed through internal interactions based on innate DNA information, as well as new internal interactions learned through external stimuli and the differentiation of individual characteristics through constant interactions with other individuals. In other words, human personality is more influenced by nurture than by nature.
