By: Kevin Canaber

Metaphors are helpful in explaining concepts, but if not used carefully, do the exact opposite. Teachers that use metaphors can potentially cause the wrong and backward developments of the student’s future knowledge.

I had an experience with a science professor who was teaching anatomy concepts. She could easily use the terminology and phraseology in anatomy that has survived centuries, but she wanted to invent her own metaphors. I suspect she wanted to brand herself and her work.

Yet, there are already metaphors in anatomy that are being used effectively, and are handy for illustrating complex concepts. Why this teacher wishes to introduce new ones and forego the classic ones is outside of my comprehension.

For example, the adrenal glands secrete cortisol; our bodies have a “fight or flight” response to threat; our heart rate can increase or decrease in physiological response to our thoughts.

Now imagine a teacher attempting to teach these three examples in invented metaphors. Imagine she says our adrenal glands perform cortisol showers; our bodies have warrior reflexes to respond to threats; our bodies have internal-blab-syndrome where stressful thoughts change our heart rate. She's introducing so many additional images and relations that certainly do not simplify the learning process, but makes it more complex and ambiguous.

It's important to know the difference between the metaphor and the actual subject it attempts to compare and explain. Sure, metaphors are handy at illustrating concepts, or at triggering recall toward a primary point, so long as you keep in mind it itself is not the primary point. It is only a means of understanding the primary point. Metaphors are tools to achieve a specific end but is not the end in itself.

The problem is, there are professors treating metaphors as an end and not a means of understanding. This can be intellectually harmful for the student who wishes to integrate what he’s already studied to what the teacher is trying to teach. It could create confusion when learning new things that don’t agree with the metaphor.

Moreover, when a teacher assigns a student to study her metaphor because it will be on her exam, that’s when disaster sets in. Not only does she corner students into accepting her invented terms, but they must burn the metaphor into their memory.

Imagine having to accept and study a whole chapter on something called cortisol showers. Imagine a math teacher teaching subtraction and introducing something called friendly-neighbor-digits because they borrow from each other when one doesn’t have enough to carry out a function. It is ridiculous, but it happens.

When a teacher uses a metaphor to explain something, the metaphor should not distract from the subject. A good metaphor makes a concept easier to understand, and after an understanding is reached the metaphor can be forgotten without any loss of advantage. That metaphor served its purpose.

For example, consider the fact that our bodies have an internal mechanism that controls the physiological responses of our organs based on night and day, seasonal and yearly activity. The commonly used metaphor for this concept is the "biological clock."

This is a great metaphor because the word clock conjures up images that match the behavior we are assigning to the organs. It is not vague. Just as a clock measures time, so does our organs account for time. The relation is clear and additional elaborations could only make it more obvious.

Using the word "clock" helps convey more in less words. It's not likely to be confused with the verb version of clock, where you can "clock" someone over the head. It would take some imagination to conclude we have a biological system that throws punches, so we don't have to accuse the metaphor of being ambiguous either.

A great feature of this metaphor is it has survived up to now and it is understood by almost all. Biological clock is a term science professors use in their teaching, or at least have in their general repertoire. There will be no need to unlearn it because of it potentially interfering with other concepts.

Be alert if a teacher introduces a metaphor which she invented as a form of branding her own concepts because then she is essentially creating her own subject of study. This is actually an irresponsible and careless handling of authority on the part of the teacher.

In most cases, the student registers for a class and expects to learn what's normally taught in that class. Nothing extra. No brand new ideas invented in the teacher's mind. In some cases where the student actually felt helped, then her metaphors were the perfect fit. Ultimately, it is the student who will decide if they've been helped or misled.

If a teacher's metaphor is confusing, go to the original source for clarity. Visit a library and check out reputable college textbooks and look up the exact terms the metaphor was trying to explain.

Evaluate the true meanings and see if the invented metaphors were necessary at all. Another option is to communicate with the professors themselves, so long as they are willing to listen to feedback from students. They might change their use of metaphor but don't count on it.

Other ways of avoiding the metaphor problem include asking questions whenever a confusing metaphor is used. A student can also ask other professors of the same subject to verify meanings. A more objective approach might even be visiting the professor during visiting hours and asking for clarification of every single confused concept.

Teachers Should Be Careful With Their Metaphors