MBTI nature vs nurture

By James Kim 

Is is interesting to ponder if whether or not personality types are solidified at birth, or through life. This is not to say that we are incapable of changing out actions or abilities, but really in that nature or life proivdes us with the type that enables us to be truely happy.

Quotes such as "In my later years, I had the game all wrong. The game was to figure out who I already was" and "know thyself"

These quotes seems to suggest that we are born with a certain type. So the main question becomes:

is personality types formed by nature or by nurture?

Assuming that MBTI is the correct form of typing personalities, then if personalities are formed by nurture, then we are born with a blank slate. Such in a way that during infancy, we are able to experiment with the different types and see which ones are most strongly impressed upon us. This usually being from the caring guardians. IF this is the case, then it is possible to break down out natural preferences and assume any of the 16 MBTI type freely. The discipline to do so would be rather simply if there aren't any other complications.

If personality types are formulated by nature, then it is a function of DNA or out genes given to us by our biological parents. Since our personalities are ingrained in us by the genome, we are then forever linked to that personality. This also means that we can assume any of the 16 personality types, but it would be much harder to do so than if by nurture.

For this question, how can we best go about testing such a thing?

One of the first things that comes to mind is that of situations when the child is raised by non biological guardians early in the child's life. This meaning that the nature element is isolated from the nurture element. Yes it is true that from nature there are mutations that happen, however over a large sample size, such mutations should be well with a controlled mean or standard deviation.

The test would then be somewhat simple. You calculate the possibile type for the child as a function of the difference of the 2 parents. For instance, if the parents are 1 letter off, then the child can be only 2¹ = 2 different outcomes. similarly is the parents are off by 2 dimensions, the possible child types are 2² = 4. The maximum possibility would then be 2⁴ = 16. If over a large sample size, the number of calcuation matches child personalities are found, then one can argue that personality types are provided by nature, within a standard deviation in respect to natural mutation. If the results are found that the distribution somewhat more flatlines, or an even distribution, then it would seem that it would have to do more with nurture, or more specifically, that we are born with blank slates.

Test Scenario 1: artifitial insemination, whereby the semen is selected and implanted into a womb.

Test Scenario 2: twins. The twins should all have the same MBTI type given that the embryotic seperation happens at the correct stage. This is also interesting to discover when the personality trait is formed within the womb.

Test Scenario 3: twins seperated at birth. This is an interesting case whereby if the wtins reunite later in life, they should still have the same personality type. The best cases here are if the guardiam parents are different from the child or outside of the calculated possibilities. (british news about seperated twins who got married)

Test Scenario 4: adopted child from birth. "baby on the door step" This scenarios is illuminating because the personality types of the birth parents, and the child rearing parents are random, and perhaps on the opposite sides of the spectrum.

Further thoughts

1. If the personality type is by nature, then there is a personality gene somewhere in our makeup. Perhaps not so tacky as finding the gene responsible for extravertedness or introvertedness, but even perhaps a combination of genes that make up each of the 4 dimensions of MBTI. Perhaps not a gene that labels is as such, but more of a gene system, or gene group responsible for our natural preferences.

2. It may be interesting to survey the population every 5-10 years to see if there is a resemblance of MBTI type via nature in accordance with evolution. It is said that there are more sensing people in the US than there are Intuitives. Is this because of natural selection? Thinking back to mating practices, when the jocks were popular, lots sensors were born within statistical norms. How about the competing fads? Like the geek fetish and artist fetish? Would these people mate more towards the intuitives? It would be interesting to map evolution in regards to personality types.