How Teaching Benefits Teachers

Education is obviously of enormous value to students of all ages. Often overlooked, however, is the incredible value of teaching to the teacher, specifically the cognitive benefits a teacher gains.

The idea that we achieve better understanding of a concept or subject by teaching it to someone else is not new. The Roman philosopher Seneca (ca. 4 BC–65 AD) wrote, “Men learn while they teach.”¹ Other authors have since expressed similar ideas. But what exactly are the cognitive benefits of teaching and how do they manifest?

As we shall see, teaching serves not only to refresh the teacher’s memory of the subject, but also to clarify, enhance, and deepen his understanding of it. These are reasons why those with the requisite knowledge and interest may want to consider teaching, even if only as a part-time or occasional complement to another career.

Whether one gives a single lecture or a whole series of them, the allotted time and the rate at which students can grasp new material limit what can be included. A teacher, therefore, must decide what material is important enough to include and what must be left out. To do so, he must determine (perhaps for the first time) the essential concepts and principles of the subject. This is true whether he is giving a one-hour cooking workshop or a series of advanced college lectures in physics.

For example, suppose the teacher is preparing to teach a course on the history of the Industrial Revolution. There are numerous facts he could include (such as a list of inventions or a list of events and their dates), perhaps far more than he could fit into several courses. Unless he distills the subject to its essential principles and files the relevant facts and examples under these—a process that greatly advances his own understanding of the subject—he will have no rational means of deciding what to include and what to omit. He may select a subset of facts at random, which, unfortunately, is the method of many so-called teachers today. But doing so will handicap his students’ ability to think clearly about the subject, requiring them instead to proceed by means of rote memorization. This, of course, is not teaching—and the would-be teacher derives no cognitive benefits from it.

After selecting the essential material, the teacher must decide on the logical order in which to present it. The hierarchical nature of knowledge means that students cannot understand advanced concepts without first learning the basic concepts on which they depend, nor can they understand these without a grasp of the facts on which they rest.² In some cases, the material necessitates a particular order (e.g., arithmetic must precede algebra), whereas in other cases, the teacher has a range of viable options (e.g., the order in which to teach John Keats’s poems).

Many college professors today, especially in the social sciences, offer courses that are mere disparate collections of topics with no attempt at integration or logical progression. For example, some teach microeconomics (the study of economic decision making by individuals and firms) and macroeconomics (the study of the economy as a whole) as almost completely separate disciplines, even though understanding the latter logically depends on understanding the former. In turn, understanding microeconomics depends on understanding more basic concepts such as values, trade, goods, and services. By contrast, other teachers present material to students in a logical order, which requires skillful integration and analysis and helps the teacher clarify (or further clarify) his own understanding of the subject.

Of course, students and teachers approach material from different contexts of knowledge, and one way a teacher can bridge this gap and communicate his knowledge or experience is by defining key terms. In order to convey ideas clearly, a teacher must define every new concept he covers in terms of its essential characteristic(s).³ In so doing, he defines concepts in terms of other concepts, which, if done properly, reveals the logical and hierarchical relations between concepts. The teacher thereby profits in two ways: First, he further clarifies his understanding of the essential characteristics of the concepts he uses; and, second, he sees more clearly the logical hierarchy of concepts, which helps him trace abstract concepts back to more basic ones, all the way down to observable facts. For example, he may define a “market” as “a place where buyers and sellers meet to determine prices and exchange goods and services.” This captures the essence of the concept and points him and his students to the observable facts that give rise to it.

Because the teacher generally knows much more about the subject than his students, he must define concepts in ways that will make sense to them, which also enhances his grasp of the subject. For example, when teaching arithmetic to first-graders, he may define “addition” as “combining two or more things.” If, instead, his definition refers to “set theory,” an advanced mathematical concept, he will merely confuse his students. But, as their knowledge progresses, he can offer more advanced definitions. For instance, he can broaden the above definition of “market” to capture the facts that people exchange financial assets and use computer networks to do so, as in, “a market is a venue where buyers and sellers determine prices and exchange economic goods and services.”

An indispensable component of teaching any subject is providing specific instances or applications of the material. Ideal examples are concretes that students already are familiar with and that illustrate the lesson being taught. Examples complement definitions in that both serve to tie abstract concepts to observable reality. When teaching new subjects or updating his course material, the teacher may need to find examples to illustrate an abstract point. Perhaps, while teaching economics for the first time, he’ll realize that he doesn’t know of societies that have employed the gold standard. He can bolster his knowledge of the subject and confidence in presenting it by finding examples. By identifying these examples, he concretizes an otherwise “floating abstraction”—a concept disconnected in his mind from any basis in reality—which, in turn, helps his students.⁴

Of course, the benefits mentioned above apply to other forms of communicating knowledge, such as writing a book. Live interaction with students, however, is unique to teaching, and the benefits are substantial. A student’s question might reveal gaps in the teacher’s knowledge or fog in his thinking, and this feedback can help him hone his understanding.

The cognitive benefits of teaching are not automatic; they require ongoing effort. Teachers who blindly follow a textbook and do not search for principles, logical hierarchy, contextual definitions, or reality-based examples will not advance their understanding. Take, for instance, a physics teacher who rattles off memorized mathematical formulas and makes no effort to understand (much less teach) their real-life applications. His reliance on rote memorization and floating abstractions will not lead to cognitive growth but to stagnation.

Teachers tend to profit most when teaching a subject for the first time. That is when many discover the greatest number of gaps in their knowledge. But because the process of acquiring knowledge is open-ended, teachers can continue deriving benefits even after teaching a subject for many years. They can find new examples or applications to explore, and new students bring interesting new questions. Plus, as a teacher’s knowledge and interests expand, he may want to teach different subjects or more advanced courses in his field of expertise.

You need not make teaching your full-time job in order to enjoy its benefits. You can reap the rewards by tutoring, offering classes at a local library or community center, or even mentoring a promising coworker. Opportunities abound to help others clarify their thinking while clarifying your own. And given the intimate connection between clear thinking and good living, few win-win relationships are as mutually beneficial as those one develops while teaching.

About Arie Vilner

Arie Vilner is a day trader in New York. He has taught economics and finance at New York University and Brooklyn College.

View all articles by Arie Vilner →