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1-Page Summary of The Nurture Assumption

Overview

As a parent, you can’t help but feel proud of your child. You’re also well-versed in parenting manuals and always set on doing the right thing.

But, as surprising as it may seem, parenting has little to do with a child’s personality! It seems like we believe that parents are the ones who shape their children. However, if this is not true and parents don’t determine how kids turn out, then who does? These questions will be answered by these key points.

In addition, you’ll learn about a boy raised as a girl and vice versa; the differences between identical twins who were separated at birth; and how two chimpanzees raised a human child.

Big Idea #1: The nurture assumption – that parenting plays the key role in a child’s development – is dead wrong.

We all have wondered about how we became the person we are today. This has led people to believe that our genes or upbringing play a large role in shaping us. However, most of us tend to lean towards the latter, nurture assumption because it’s more probable than nature (our genetics). It is also widely believed that parents shape their children’s personalities and characteristics. People tend to assume this because it seems logical for them as well as being a cultural norm.

However, as you’ll see, the evidence amassed by developmental psychologists in support of the “nurture assumption” has been biased from the beginning. The nurture assumption is a huge cultural myth because children are influenced by many people outside their family such as friends and teachers.

Because of the nature of scientific research, it’s hard to study the relationship between a child’s upbringing and her character. Scientists can’t just take 500 children away from their parents for the sake of research.

Instead of looking for a cause-and-effect relationship between shyness and punishment, researchers are content to look for correlations. For example, if a child is punished often, he or she tends to be shy. This makes it difficult to find other factors that could contribute to this correlation.

Big Idea #2: Compared to our genetic makeup, the home we’re raised in barely affects our character.

If you have siblings, then you probably feel like they’re nothing like you at times. But it’s not surprising that there are similarities between siblings because of their shared experiences growing up together.

Genes impact personality because they’re responsible for certain traits. For example, identical twins have the same genes and often end up with similar personalities.

The Minnesota Twin Family Study was conducted on two pairs of twins. They were genetically identical, but raised in very different environments. Despite the differences in their upbringings, they both developed similar habits and likes/dislikes as adults, such as biting their nails and driving the same car.

Not only did they have the same names, but their sons were also named James Allan and James Alan. That’s pretty amazing evidence of how genes influence our development. But it gets even more interesting: twins who grow up in different homes are just as similar to each other as those who grow up together. So if growing up together doesn’t make twins any more similar, what does? It turns out that having a lot in common is all about genetics—not upbringing or environment.

For instance, a study in Minnesota looked at the personality traits of twins and found that they were only 50% similar. This means that there was no significant difference between them and twins who grew up separately.

From the data above, we can infer that parents have little control over how their children turn out. However, this is hard to believe since everyday life influences a child’s character and behavior. We’ll explain why in the next key point.