Nature VS Nurture Theories of Personality in 21st Century

Nature vs Nurture theories has wasted a lot of energy for human beings. Plato is considered the first to realize that you are made of not only flesh but also an intellectual soul. However, the issue may be much older.

In Greek Mythology, when the gods created man, they endowed him with divinity. However, their creation (man) started challenging them. They feared his potentials and decided to deprive him of his might. So, the big question of the day was, “Where to hide his divinity?”

They considered heights of icy mountains, limits of shining stars and pits of the earth. But every place was accessible to man’s capabilities. Finally, they decided to hide it within the man himself.

Since then man has been climbing icy mountains. He has navigated deep seas. He has traversed the moon. His machines have even touched Mars. But he is still looking for his ‘lost paradise’.

Hey buddy, it’s inside you!

Today we call this lost paradise, personality. So, how does our personality come into being? Is it inheritable? Is it natural? Is it an outcome of the environment? Do we have the will to change our behaviours or are you are bound to follow our genetics?

Nature vs Nurture theories focuses upon these issues. And new discoveries in genome and quantum physics have revived the debate. Incidentally, the more they discover, the more they bewilder. The abstraction continues intensifying.

How to Define Nature vs. Nurture Theories

Allow me to attempt to bring this into something all of us can understand. There are three distinctive schools of thought.

1-Personality is Natural:

This group believes that your personality is a result of an evolutionary process. You inherit behaviours due to the complex interaction of genes. They control your behaviours. So you don’t have free will to act otherwise.

2- Personality is Nurtured:

This group argues that you don’t get your personality inherited. Your mind is a blank slate at your birth. It is your environment, education and culture that make up your behaviours. There are differences though on the issue of ‘free will’ to change your behaviours.

3- Personality is Spiritual:

This group claims that your personality is a result of neither nature nor nurture. It is a gift of some deity. This group is also split on the issue of ‘free will’.

Now, what does psychology have to say about this conundrum?

Nature VS Nurture Theories and Evolutionary Psychology

Darwin’s theory of evolution led William Hamilton, George Williams and many others to the idea of personality evolution. They proposed that like physical organs, your personality is a result of natural selection for survival of the fittest. You do as your genes dictate.

They suggest that fear of death, fear of injury, fear of snakes, shyness, addiction, criminality and sexual orientation are the main examples of inheritable behaviours. Steven Pinker (2004) includes religiousness, liberalism and conservativeness in the list. William Paley considers cognitive capabilities, temperaments and cheating behaviours inheritable.

However, there is strong criticism of this approach.

First, there is no single universal behaviour that can be proved evolutionary. Even fear of death, which seems natural to all, is overridden in crusades, suicides and suicide bombings. Second, you are made of 25,000 to 30,000 genes. They are mere twice the number in a fruit fly. Chimpanzees share 95% of your genetic characteristics. However, they don’t share even 10% of your behaviours. Third, people don’t differ in behaviours as they do differ in skin pigments. Extroverts, introverts, optimists, pessimists, criminals, liberals etc are found in all societies and cultures. Even identical twins (with 100% similar genes) and fraternal twins (with 50% similar genes) behave differently in most cases.

Plus, there hasn’t been a genome scientist that has related genes or a set of genes with any kind of behaviours. Just look at the vast number of living organisms and fossils we can look at and all of them suggest intermediary stages to the physical evolution. However, no such intermediary stages are available for personality evolution.

Nature vs. Nurture Theories and Physics

The discoveries in physics have always provided new meat to the nature vs nurture theories. The conclusions of Newton and Einstein helped people to believe that future events can be predicted with the help of true knowledge of matter and natural laws. This led psychologists to suggest that your future behaviours can be predetermined. The whole mechanism of psychometrics follows this hypothesis.

However, quantum physics has changed the situation altogether. Evidence proves that you can’t make two (almost) simultaneous measurements of observables correctly. For example:

  • Position and momentum of a particle

  • Position and direction of a particle

  • Time and frequency of a sound wave

  • Wavelength and magnitude of a sound wave

The list goes on…

Quantum physics has shaken determinism. So much so the scientists have to devise the “Heisenberg uncertainty principle” which challenges that any physical event can be predicted precisely in time and space.