Nature is more important than nurture because genes determine who we are
Although our environment influences us, genes determine how it affects us. For this reason, nature is more important than nurture.
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People are a summation of their habits, temperaments, and experiences. However, where do these things that define us come from? Psychology has long been debating whether they stem from our genes or our environment. Settling the debate will expand our currently limited understanding of human development.
There is no software without the computer code underlying it. Similarly, there is no us without our genes. Through inheritance and mutations, genes create a unique map of just who each one of us is. Our environment may change how our genes manifest, but they manifest just the same, meaning genes are what actually create us. Our genotype is both the collection of our genes and how they interact to produce us. The way in which different genes interact in different ways produces infinite permutations of people despite having almost identical genes.  For example, consider two children with a tall mother and short father. The combination of genes each child inherits (i.e. genotype) will determine exactly how tall they grow to be. Their height, or expression of their genes, is a phenotype. If one is taller than the other, this is clearly genetic because the children grew up eating the same food. Eating different food would be an environmental influence, which can also impact us, such as with a malnourished child whose growth is stunted. Although our environment can influence our phenotype, we are not our phenotype. We are our genotype because genes control things like intelligence, personality, and temperamental habits (i.e. whether we’re night owls or morning birds) on top of our physical traits.  What are we, if not more than a collection of our physical and psychological characteristics?
A computer game can be played in almost infinite ways despite each player having the same code. What makes millions of different versions that each individual player creates? Their interactions with the game. Genes work similarly. They are the code, but our environment takes us from a possible person to a person. The only people that are mere genetic codes are embryos because genes do not otherwise exist in a vacuum. There is no genotype without a phenotype, and what our phenotype depends entirely on the environment. Since we are our phenotype once we develop, both the environment and our genes create us. Genes are not more important.
Rejecting the premises