Tuesday, January 24, 2012

Nature vs Nurture

Nature Vs Nurture

There is an issue that has been conferred upon by philosophers in the past and still so by scientists today. This issue is whether heredity or environment plays a greater role in the determining or shaping of an individual's behavior. It is known as the nature versus nurture debate.

Numerous generations before us have deliberated on the reasons behind the development of human behavior. There have been many theories formulated to explain why humans behave the way they do. The surviving theories for behavior derive from physiological and sociological explanations. However, the two explanations have not always been compatible with each other. The famous nature vs. nurture debate over human behavior resulted from conflicting views between proponents of the physiological (nature) and sociological (nurture) explanations. Throughout history, research has swayed popularity back and forth between the theories. Yet, theorists have broken down the line separating nature and nurture. As of today, people utilize both explanations to explore human behavior.

Way before our time, early philosophers endeavored to understand the human behavior. As early as 350 BC, such philosophers as Plato and Aristotle tried to understand behavior. The question of nature or nurture as the primary drive can be traced to these times. Plato believed behavior and knowledge was due to innate factors. Plato theorized that all knowledge is present at birth. Plato also believed that the environment played a part in human processes, but he thought it had a unique role. He believed the environment did not teach people anything new, but its purpose was to remind people of information they already knew. Although Plato's views are not supported today, he laid the groundwork for other researchers to follow.

Philosopher Aristotle theorized a different idea about human behavior. He presented “Tabula rasa” the idea that humans are born into the world with a "blank slate" and people's behavior and thoughts are due to experience. Aristotle's idea of the tabula rasa is not believed today.

During the late 1700s, the nature vs. nurture debate began to heat up between philosophers. Internalists (nature) and empiricists (nurture) wrote literature back and forth trying to prove their beliefs and disprove the other’s theories. Two philosophers, G.W. Leibniz and John Locke, were main representatives of their respected explanations. Leibniz promoted the internalism point of view.
John Locke campaigned for empiricism. Like Aristotle, the philosopher believed that human’s thoughts and actions were determined by their unique experiences.
From the 1920s to 1950s, behaviorism and nurturism dominated psychology. The domination did not last forever. In 1929, behaviorism came under attack by psychologists who believed genes were the key to human behavior.
The Nature Theory – Heredity
Scientists have known for years that eye color and hair color are determined by specific genes in each human cell. The Nature Theory takes that more abstract trait such as intelligence, personality and sexual orientation are also in an indivual’s DNA.
The most debated issue to the nature theory is the existence of a “gay gene”. In debating sexual orientation, much is unknown. And there is not answer to know if this is hereditary or not.

A large number of the study of twins was undertaken by Thomas Bouchard of the University of Minnesota starting in 1979. He collected pairs of separated twins from all over the world and reunited them while testing their personalities and IQs. Other studies at the same time concentrated on comparing the IQs of adopted people with those of their adopted parents and their biological parents or their siblings. Put all these studies together, which include the IQ tests of tens of thousands of individuals, and the table looks like this:

Same person tested twice 87%
Identical twins reared together 86%
Identical twins reared apart 76%
Fraternal twins reared together 55%
Biological siblings reared together 47% (studies show that reared apart about 24%)
Parents and children living together 40%
Parents and children living apart 31%
Adopted children living together 0%
Unrelated people living apart 0%