Nature or Nurture? A question that has been asked very frequently in recent decades. On one side of the argument some people believe that a person's mentality comes from their genetic make-up. On the other hand, some believe that a person's mental traits are determined by their environment and how they were "raised". Although there is a lot of evidence to support each theory, I personally believe that is not a single reason, but both.
In my personal experience I have found that both genetics and environmental variables have helped develop my personality and mental traits. As a young child I was fairly intelligent and had a strong desire to learn. In contrast, my sister at the same age was not interested in learning at all and would much rather participate in physical activities. As she is only my half-sister (we have different fathers), I believe that this was a factor but I don't believe this was the only factor. When I was young my parents had much more time to spend with me and my Mother didn't work, therefore, I got a lot more attention than my sister and my mom was able to teach me to read before I entered school. While my sister was young my mother worked all of the time and my sister got very little attention from either of my parents and she is a very poor reader. I am not saying that reading is a way to scale someone's intelligence, because its not, but I believe depending on the environment that a child is immersed in, the more drive the child will have in learning. My beliefs are also based on my father and my sister's father. My sister's father never attended college, did not do well in high school, but he is very physically fit. On the other hand, my father was very successful in high school and was less physically fit. There are so many variables that have to be accounted for when testing this theory that it is almost impossible to reach a conclusion. In my opinion genetics and environment are both reasons.