Sometimes trying to understand what other people know and don’t know can be really challenging. As adults it may take us a while to figure out how to give driving instructions to someone who is new in town or how to tell a joke to someone who is just learning English. No wonder, then, that coming to understand that other people might not know what we know is one of the biggest milestones in development for children. But knowing what we know should be easy, right? Well, not always. Research suggests that children (and sometimes adults) struggle to understand what they themselves know and when they came to know it.
One of our favorite studies investigated this topic directly with children. Marjorie Taylor and her colleagues taught 4-5 year olds a series of new facts embedded in short stories. These were facts children did not know before the study began (for example, that a cat’s whiskers help it gauge the size of tubes). The children also heard stories embedded with facts children already knew (for example, cats chase mice). The researchers later asked these children if they’d just learned the facts or known them for a long time. Nearly all 4-year-olds believed they knew the new facts for a long time—in fact the same number said they’d known the novel facts for a long time as had said they’d known the familiar facts for a long time. 5-year-olds did a bit better, but still nearly half mistakenly believed, upon learning a new fact, that they’d actually known it all along.
One might think that children are just trying to look smarter than they really are or that they lack the intellectual humility to recognize that they did not know something before the experimenter told them, but most likely they actually believe that they knew these facts all along. The tendency to think we knew all along something that we actually just learned is a tendency even adults are susceptible to, though to a less extreme extent. You would probably recognize that you didn’t know that a cat’s whiskers help it gauge the size of tubes, but you could mistakenly assume that the right answer to a question about the capital of Australia is obvious, after reading an article about Canberra.
Another instance of not knowing exactly what one knows is the illusion of explanatory depth. This is the illusion that one can explain a phenomenon deeper, or with more details, than one actually can. As an example, Frank Keil and his colleagues ask people if they know how a zipper, air conditioner, or helicopter works. Adults start out by thinking they know and that they can easily explain the relevant mechanisms. They are then asked to do so—by providing a step-by-step description. Perhaps not surprisingly, given this blog’s title, but more surprisingly for participants, they realize they were mistaken about the depth of their knowledge. The researchers studied this phenomenon in children, too. Just as they had done with adults, they asked kindergarteners, second graders and fourth graders how much they knew about how a toaster works, for example. Then they asked children to explain it and even read to them an expert description of how a toaster works. At the end the researchers asked the children again how much they knew about those devices. Like adults, children think they know more about how devices work than they actually do. However, contrary to adults younger children (the kindergarteners in this study) tend not to realize the holes in their knowledge, even when asked to complete this task. They, much like Olivia, in the clip above, believe they understand the process in its entirety. Thus what appears to change over development is not the overstatement of what one knows, rather the ability to confront evidence to the contrary and update our assessments. So next time your grade schooler tells you that he does in fact know how to load the dishwasher, it may be worth watching nonetheless!
Copyright 2013 Sara Haga and Kristina Olson
Sara Haga is a post-doctoral research associate at the University of Washington investigating the developmental origins of intellectual humility, funded by the Fuller Theological Seminary /Thrive Center in concert with the John Templeton Foundation. Kristina Olson is an assistant professor at the University of Washington and director of the Social Cognitive Development Lab. Follow the lab on Twitter @scdlab
Kristina R. Olson, Ph.D., is an Assistant Professor of Psychology and Cognitive Science at Yale University.