If we dig a bit deeper into this idea, there are two related aspects of curiosity. The first is that it is important to try to explain how the world works. That is, curious people spend a lot of time asking the question why? But, having asked why? it is also important to try to answer that question. So, curious people should not just wonder about the world, but also explore it, taking things apart and trying to understand what makes them tick. As I discuss in my book Smart Thinking, it is crucial to develop high quality knowledge about the way the world works if you ultimately want to be able to solve new problems.

An important question is whether creating explanations for things guides people's search for new knowledge. This question was addressed in a clever study published in a 2012 issue of by my colleague Cristine Legare. She studied children between the ages of 2 and 6.

In these studies, children were exposed to both surprising and unsurprising events. First, this study explored the kinds of explanations given to these events. In particular, kids should be most focused on trying to explain surprising things. Second, the study examined whether the type of explanations that kids give to surprising events influenced the way that the kids played with the objects later.

At the beginning of the experiment, children were shown two boxes with lights inside them. The boxes were designed so that when some objects were placed on top of them, the boxes would light up. (The boxes were actually set up so that an experimenter watching the study could turn the boxes on and off, but from the child's perspective, the boxes lit up when certain objects were put on them.)

The objects used in this study were blocks of different shapes and colors. All of the blocks were actually boxes, so that if you looked carefully at them, you could see that they opened up. A block of a particular shape and color (say a red triangle) was placed on top of one light box, and then the other. When the block touched the box, it lit up. Children were told, "This is a blicket." Then, another block of the same shape and color (another red triangle) was placed on each of the boxes. Once again, when the block touched the box, it lit up, and it was labeled a blicket. After that, a different block (perhaps a green hexagon) was placed on the box. This time, the box did not light up. The child was told "This is not a blicket."

After being introduced to the box and the blocks, children saw two more demonstrations. Now, two light boxes were put in front of the child. The blicket was placed on one box and the not-a-blicket was placed on the other. The first time this happened, the box with the blicket on it lit up, and the box with the not-a-blicket did not. The key part of the experiment came when the next pair of blocks was tried. In the consistent condition, the blicket made the box light up again and the not-a-blicket did not. In the inconsistent condition, neither block made the box light up.

Children were asked to explain what just happened. After giving an explanation, the children were allowed to play with the blocks for a while. After completing this part of the study, the children each participated in the other condition as well. So, each child did both the consistent and inconsistent conditions.

When children saw a consistent event, they rarely saw the need to explain what happened. If blickets consistently made the box light up, then the best explanation for why a new block made the box light up was that it was a blicket.

The inconsistent events were the ones that really required an explanation. In this case, there was a block that once made the box light up, and now a new one failed to make it light up.

Children at all ages tried to come up with explanations for what went wrong. At each age group, there were two general types of explanations that children gave. Some tried to explain why the block did not make the box light up. They might way that the block ran out of batteries, or that placed on the box the wrong way. Others explained the unexpected event by focusing on the category the object belonged to. They would say things like, "I guess that one isn't really a blicket." Overall, about half of the kids gave explanations for why the object didn't make the box light up, while about a third of the kids focused on the category of the objects. The explanations given by the rest of the kids were some other type.

The type of explanation kids gave was related to the way the kids played with the objects later. The kids who tried to explain why the block did not make the box light up spent more of their play time testing the blocks than the kids who gave other types of explanations for what happened. They would stack a few blocks on the machine, open up the blocks, and tried different combinations of blocks on the boxes.

The children who gave explanations based on the categories of the objects spent more time than other children sorting the blocks into categories. They would place a block on the box, and if it lit up, they put it in one pile, but if it didn't light up they put it in another pile. This kind of behavior will not let children understand anything about why the blocks make the box light up, it just confirms that some blocks make the box light up, while others don't.

A fascinating aspect of these findings is that there is a clear relationship between curiosity and exploration. Starting from the age of 2, when a child asks the question why, this question is followed by an attempt to answer that question. That means that giving explanations that focus on understanding why things happen drives a better understanding of why the world works as it does. Merely categorizing objects in the world does not promote this same kind of understanding.

There are two important questions for future research raised by these studies. First, are there big differences between kids in how likely they are to give why explanations? Is a kid who asks why today also more likely to ask why tomorrow?

Second, can we teach kids to be better at asking why? Because the kids who ask why are engaging in behaviors that promote smart thinking, it would be wonderful to help make that a habit even in kids who don't generally ask why on their own.

And, of course, even as adults, we should spend a lot of time asking why.

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