Chapter 4

Understanding how things work

Smart Thinking — Art Markman, PhD

• Causal knowledge is the information you know about how the world works.
• The quality of our causal knowledge is less good than we think it is.
• We can improve the quality of our causal knowledge through self-explanation.

The big question: Why?

It turns out that to one degree or another, everyone wants to know why the world works as it does. However, engaging in Smart Thinking requires exceptionally good answers to that question. Getting answers to why questions plays a key role in everyday life.

• You are using your knowledge about why things work to help you solve a problem.

The ability to think about why things work and what may be causing problems when events do not go as expected seems like an obvious aspect of the way we think. It is interesting that this ability to think about why things happen (and what has gone wrong with them) is one of the key abilities that separates human abilities from those of just about every other animal on the planet.

• Asking why allows people to create explanations.
• Psychologists call the ability to generate explanations for things causal reasoning.
• Our ability to ask and answer the question why leads us to build on the innovations of past generations to create new more sophisticated tools.
• The ability to think about why things work is a huge part of what makes humans smart. The more causal understanding you have, the higher the quality of your knowledge overall. And High-Quality Knowledge is central to the formula for Smart Thinking.

The Organization of causal knowledge

To understand the power of causal knowledge, it is important to be aware of how your causal knowledge is organized and how it is used to solve new problems. Your causal knowledge is organized around explanations. That is, causal knowledge is always related to a particular why question. There are two important aspects of causal knowledge that result from the relationship between causes and explanations.

The first key aspect of causal knowledge is that there are often many different explanations for the same event. These explanations typically account for a variety of different factors that may affect a situation. Some of these factors may be physical, whereas others may be social or even psychological.

The second important aspect of our causal knowledge is that it is nested. That is, whenever you give an explanation, it is always possible to ask why again and to give an explanation at a more specific level. Five-year-olds learn this trick quickly, and they will continue to press adults for more and more specific explanations of an event.

The key here is that each explanation addresses a particular question. Once you build that explanation, though, it is always possible to ask another more specific question. Answering that question involves generating another more specific explanation. And so on. That process never ends.

Causal knowledge and expert problem solving

• The reason we care about causal knowledge is because it is crucial for solving new problems.
• The deeper my causal knowledge, of course, the more complex the problems that I can solve.
• When we classify someone as an expert, there are usually two dimensions of expertise that are important.
• First, experts have skills (or habits) that allow them to perform actions that a non-expert cannot perform.
• Second, experts have deeper causal knowledge than non-experts.

The two key elements of causal knowledge—1) that there are multiple explanations for the same event and 2) that causal knowledge is nested—explain why it is so difficult to develop extensive causal knowledge. An expert must know about the many types of explanations that relate to her domain of expertise, and the expert must have knowledge of many of the nested levels of explanation that are part of that domain. Because of the volume of knowledge that must be acquired, it is impossible for someone to be an expert in every area.

So, causal knowledge is a crucial part of your ability to solve new problems. If you understand why something works, then you can use that information to determine what has gone wrong when you are surprised at some outcome. This causal knowledge is also useful for suggesting ways to fix these problems. Expertise consists of both skills that relate to solving problems as well as causal knowledge that goes beyond the norm. Causal knowledge is a crucial part of what allows experts to solve problems that baffle non-experts. Putting all of this together, then, causal knowledge is exactly the kind of High-Quality Knowledge you need for Smart Thinking.

Leveraging the Expertise around You

You have probably heard it said that it is important to know what you know and to know what you don’t know. As it turns out, it is also important to know who knows what you don’t know. From a young age, of course, we begin to discover that different people are likely to have a range of types of expertise. The research of Frank Keil and his colleagues demonstrates that even five-year-olds believe that someone who knows how refrigerators work is more likely to know how stoves work than to know what makes people happy or sad. If you want to be smart, you clearly want to improve the quality of your own knowledge. In addition, you want to make sure that you know whom to call when you reach the limits of your knowledge. Spend time paying attention to which people you encounter who seem to have important knowledge that you are lacking. Use those people as resources to help you extend what you know.

The Illusion of Explanatory Depth

How good is your causal knowledge?

If you found some gaps in your own causal knowledge, then you are not alone. Yale psychology professor Frank Keil and his graduate student Leonid Rosenblit conducted a study with college students very much like what you just did. They first asked people to judge how much they knew about a number of different devices. Then they had people generate explanations for devices that they thought they understood. The central finding of this research was that there were many devices that people believed they understood but really did not. They expressed confidence in their ability to explain the way it worked, but when they actually had to produce that explanation, they failed. Rosenblit and Keil call this difference between people’s belief about the quality of their causal knowledge and their actual ability to formulate an explanation the illusion of explanatory depth.

Why does this happen? When you are asked whether you know how something works, you do not generate a complete explanation for it before answering. Instead, you use some shortcuts to make this judgment. First, you try to imagine the mechanism at work. So if you can form an image in your mind of the device at work, your confidence that you can explain it will increase. Of course, if there are key elements of the process that are hidden from view, then these elements will often be accompanied by a gap in your causal knowledge. Second, explanations are nested. When you try to decide whether you can explain something, you try to retrieve some of the explanation. You assume that if you can retrieve some of it, then the rest will follow. However, sometimes you have a very general explanation without any more specific knowledge underlying it.

Fixing the Illusion of Explanatory Depth through Specific Thinking

It is possible to improve your judgments about the quality of your causal knowledge by thinking specifically. At any given moment, you have lots of options for how you think about things in the world.

You can generate a mind-set to think about things specifically or abstractly. There are lots of ways to affect whether you will end up in an abstract or a specific mind-set. One easy way to influence your level of construal is to change your sense of how far away something is from you in space or time.

As an example, I am often asked to travel for work. Usually, I get an email or phone call several months before the trip asking me to give a talk or go to a conference. Because the trip is months away, I tend to think about it abstractly. I focus on issues like whether the conference will have interesting people at it or the location is one that would be enjoyable to see. After I agree to go on the trip, I put it on my calendar. As the date creeps closer, more specific issues start to arise. I have to reschedule meetings to accommodate the trip. I have to arrange things with my family to make sure the kids get to school. I begin to wonder why I am going on this trip at all, given how busy my schedule is. Because dates that are far off in the future are distant from me, they don’t come readily to mind, and so they are less likely to influence my decision to go on the trip than the more abstract factors. The same thing holds true for objects that are close to you in space.

When you think about an object abstractly, the illusion of explanatory depth is particularly strong. You get a general mental image of some object and make a judgment about whether you understand how it works. When you think about an object really concretely, though, you are more likely to realize aspects of it that you don’t understand. That means that if you have to make a judgment about whether you have a causal understanding of an object, you should try to imagine that object as being right next to you. By thinking about it specifically, you will make your judgments about the quality of your causal knowledge more accurate.

Filling in the gaps of Explanatory Depth

The main method for ensuring that you have high-quality causal knowledge is to learn a lesson from teaching. There is an old saying in education that the best way to learn something is to teach it to someone else. Indeed, a cornerstone of medical education is: See one. Do one. Teach one. The idea is that when a doctor is learning a procedure, she first needs to watch someone else carry it out. That gives her a general idea of how it is done. Next, she practices the procedure until she can carry it out. The process of doing something helps reveal some of the elements of the procedure that she did not understand. Finally, teaching the procedure to someone else makes sure that she has enough knowledge to really understand how the procedure is done and why it is performed. The reason why teaching is so effective at helping you learn is that when you teach something to someone else, you have to form a complete and understandable explanation of it. Both the words complete and understandable matter here.

• Complete, seems obvious. If you get to a part of your explanation where you are not sure how to continue, then you have identified a gap.
• Explanations also need to be understandable. Often when you give an explanation to someone else, you may use words whose meaning is not actually clear to you. In this case, you have given an explanation that appears to be complete, but it is actually not understandable either to you or to the person you are teaching.

If there are any gaps in your own causal knowledge, you will find them in the process of teaching. Because you have to ensure that your explanations are good ones, you will not only identify the gaps in your knowledge, you will also work to fill them by doing additional reading and exploration to learn the information that you are missing. After all, teaching requires you to have good explanations. In this way, teaching improves your causal knowledge.

Teach yourself

Of course, you don’t actually need to be in front of a classroom to do all of that work. You can treat every topic you encounter as if you were preparing to teach it. As you read new material or hear it from someone else in a lecture, you should attempt to teach it to yourself. These self-explanations will help you find gaps in your causal knowledge. Those elements that you can’t explain are an invitation to do more reading or to ask additional questions to make sure that you learn and understand the missing causal knowledge. Even if you choose not to fill a particular gap in your knowledge, you still have a better sense of the quality of what you know. That is, you have a better sense of what you do and don’t understand. Sometimes, it is just valuable to know the limits of your knowledge.

This process of self-explanation is particularly useful when studying for exams. Many people study by rereading the material that is going to be tested and deciding whether that material feels familiar. The illusion of explanatory depth makes clear that an overall feeling of familiarity is not a good way of predicting whether you will be able to produce a good explanation later. If the exam you are taking is going to require you to give an explanation, then the best way to ensure that you can generate an explanation is to actually produce that explanation when studying.

Making a smart habit of self-explanation

It does not feel natural to explain things as you go along. You often need to read things many times before you feel like you can explain them back. That is perfectly normal, but it also means that you need to work to develop the habit of explaining things to yourself. As you develop your own skills at generating explanations when learning, you can help other people to acquire this habit as well. The best way to do that is to get people to justify or explain their conclusions in meetings and learning situations. Often, we do not ask other people to explain their chain of reasoning when they present us with new information. Perhaps we feel that the explanation would take too much time. We assume that the person presenting information to us probably knows the full explanation that led to their conclusion. Sometimes, we are reluctant to indicate to people that we ourselves may not understand the reasoning behind someone’s conclusion. We fear that by asking questions, we might betray a weakness in our own knowledge.

The illusion of explanatory depth suggests that people may often be missing key aspects of their causal knowledge. In this case, the gaps will come to light only when they are required to give explanations. In addition, when someone gives an explanation to you, you may discover that you understood their point less well than you thought at first. Getting that explanation may, in turn, reveal gaps in your own knowledge.

An invitation to learn

If you push people to explain their reasoning, you must treat the gaps in people’s knowledge as invitations to learn more rather than as signs of weakness. That is, we all know people who ask questions in the hope of playing gotcha by exposing errors in someone’s reasoning or gaps in their knowledge in a meeting. That won’t help people become smarter, though, because it will discourage people from wanting to volunteer causal information in the future. Instead, it is important to see gaps in causal explanations as opportunities to learn. This process of asking people to explain their conclusions and encouraging them to fill in the gaps in the explanations that arise from these questions promotes learning. In this way, you are doing your part to create a Culture of Smart that will help you better understand what the people around you know and will increase the quality and depth of the causal knowledge of your peers, coworkers, and associates. By asking people to explain their reasoning, then, you make yourself smarter and you make the people around you smarter as well.

The takeaway

Causal knowledge, the knowledge you use to answer the question why, is crucial for solving new problems. It allows you to go beyond solutions you have encountered before by giving you information you need to diagnose problems and generate new methods for dealing with those problems. Causal explanations are a uniquely human ability that allows us to create more complex tools by understanding the goals that people have when they act and the way that tools help those goals to be achieved.

A key aspect of causal knowledge is that it is nested: every explanation has another one associated with it that provides more causal information about why that explanation is accurate. Despite the importance of causal knowledge, you may be poorly calibrated about the quality of your own ability to generate explanations. There are likely to be many instances in which you think you understand how something works, but in fact there are significant gaps in your knowledge. You can minimize the influence of this illusion of explanatory depth on your judgments by trying to think about objects specifically rather than only abstractly. The gaps in your causal knowledge hold you back from Smart Thinking, because they represent situations for which you do not have high-quality causal knowledge to help you solve new problems. In order to ensure that you have reliable causal knowledge, it is important to develop the habit of explaining things to yourself as you learn them. A good explanation is one that is free of gaps (complete) and is also understandable. You need to make sure you do not have elements of your causal explanations that use concepts whose meanings are fuzzy to you.

Explaining things to yourself is like teaching yourself as you go along. And you have to go through the full teaching process. Don’t just start the explanation and then assume you know how it completes from there. By teaching yourself, you identify and fill the gaps in your causal knowledge. Finally, you should demand this level of explanation from the people around you as well. In this way you can create a Culture of Smart, by promoting good thinking habits from your colleagues, coworkers, and friends—as well as from yourself.