Three-year-olds are in a stage of development where they’re just learning the rules for all kinds of stuff.  So, for instance, when a kid first learns language as a toddler you’ll notice that they do what scientists call over-regularize.  They want everything to be the same. 

"That hurted my foots!"

All the past-tenses are with “ed” and all the plurals are with “s” even if that doesn’t actually make correct language.  Now I think that what kids do with gender at that same age is kind of similar.  They’re just barely getting a grip on the rules and they’re very simplistic, and they’re often kind of superficial.  They know things like girls wear pink frilly dresses and boys play in the mud.  Girls play with dolls, boys play with trucks.  

And because they’re kind of not all the way there on the concepts—most kids can’t even reliably tell you whether they’re a girl or a boy until they’re about two and a half years old—they cling very tightly to these few things that they do know.  And they can, you know, little kids, toddlers that age, are really very insistent in a lot of domains about the world being exactly the way they think it is.  And they’re the same way about gender.  They’ll relax quite a bit and get more flexible as they get older. 

In Their Own Words is recorded in Big Think's studio.

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