Diverse environments nurture us without the effects of nature

The argument

Although our genes contribute to who we are, it is our environment that really determines identity. Urie Brofenbrenner proposed a theory called the ecological model of development that explains this. We are infants with genes born into families, but those families determine who we are. How this happens depends on the family composition, how roles are divided within the family, and the quality of family interaction. However, Brofenbrenner didn’t think that families are the sole determiner of who we become. His model also explains that our development is influenced by a series of increasingly vast systems. Peer groups are one of the systems outside of families that influence us. On a broader scale, the communities we live in (i.e. Maryland or Minnesota, rural or urban, impoverished or affluent) have influence over us too. So does the culture of the society a person grows up in. All of these systems that simultaneously influence us are what mold us into who we are. Our environment might not be able to change whether we develop a disease that we have a mutation for, but what really shapes us is not the development of the disease, but how the world responds to it. This encompasses whether we have support and good treatment, as well as whether the disease is stigmatized in this person’s community/culture. This argument assumes that people do not develop in a vacuum. Even people who grow up in the complete absence of social interaction (i.e. children locked in a room) are still environmentally influenced. Even though they have the genetic capacity for language like everyone else, they don’t develop it. It is our environment that does that. So thus, the environment is more important to our development because our environment is what causes us to acquire language.

Context

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.

Premises

Counter-arguments

The fact that infants are born with genes need not be discounted entirely. As much as their family contributes to their development, so do their genes. Infants are not blank slates, but are born with some genetically-determined traits and temperaments. These influence how the family interacts with them. More social babies elicit more social responses, which increases their sociality. Less social babies are socialized with less, so they grow up to be less social. Nurture isn’t everything, because our genes determine exactly what kind of nurturing we get.

Rejecting the premises

[Rejecting P1] The premise concedes a genetic contribution and then sets it aside, which is where the argument needs its work done. 'Contributes but does not determine' is compatible with either position, and no reason is given for ranking the two. [Rejecting P2] Bronfenbrenner's model describes the environmental systems surrounding development; it was not designed to weigh environment against heredity and does not do so. Cataloguing environmental influences in detail says nothing about their share, since the same exercise could be performed for genetic influences. [Rejecting P3] The feral-children case shows environment is necessary, not that it is more important. Language requires exposure during a developmental window and it also requires the human genetic endowment — no other species acquires it under identical exposure — so the example demonstrates that both are required. [Rejecting C] The counter-argument on record identifies the mechanism the argument omits: infants arrive with temperamental differences that shape the environment they receive, with more sociable babies eliciting more social response and so more of the input that reinforces sociability. On that account genes and environment are not separable quantities to be ranked, which is what both this position and its rival assume. Behavioural-genetic studies of twins and adoptees, which are designed to make the comparison the argument asserts, consistently find substantial heritability for the traits at issue.