Monday, August 4, 2014

Metaphors Bewitch You


Do these statements sound familiar to you?

·       “An atom is like a little solar system, where the nucleus is the sun, and the electrons are the planets.”

·       “The kingdom of heaven is like treasure hidden in a field.”

·       “Working memory is a conveyor belt.”

During the last few years, as I spent time listening to Great Courses, learning about disparate disciplines like writing, philosophy, physics, history and theology, I have been struck with one recurring method used by the many teachers I’ve heard, and it occurred to me that every teacher I could remember used that same method.  What is the method?  Comparison as explanation.  Simile, metaphor, models: all of these are ways to explain one concept in terms of another, and they all depend on the ability to compare something you already know to something you want to learn more about.

When you’re learning something new, you’re standing on what you can think of as an island of existing knowledge, and you want to cross over to some new island of knowledge.  To get from one island to another you can walk over a bridge of metaphor.  That is, you can base your understanding of the new, by comparing it to something you already know. 

This is not simply an effective teaching technique, it’s also both something our minds seem programmed to do and a method we apply to our own lives without even thinking about it.  Often, when we learn about something for the first time, especially if the new topic is complex, we can get a basic understanding by comparing one thing to another.  For example, the first statement above compares atoms to planets.  By the time we start learning about atoms in school, we have typically been exposed to the solar system in previous science classes.  The comparison, then, makes sense.  It gives us a mental picture on which we can scribble mental notes.  This is very, very helpful.

But as we drive over the bridge of simile, we need to be careful that it does not collapse and drop us to our doom.  Why would that happen?  Well, the comparison can only be as good as the underlying structure of the known thing is similar to the underlying structure of the new thing.  If the two things are not extremely similar, we might make a generalizing assumption which gets us in trouble.  For example, two primates are very similar, whereas a primate and a jellyfish are not.  So, while you might deduce some similarities between a jellyfish and an ape, based on them both turning food into energy, for example, you probably don’t want to generalize a similarity when it comes to how they will react to a mirror introduced into their environment.

And, in the case of the atomic structure being like a solar system, you might picture electrons being solid objects, similar to planets.  This would be carrying the analogy, perhaps, too far – depending on the degree of detail you need.  Electrons, as explained by current quantum theory anyway, don’t “really” travel in circles (or some other relatively “flat” closed-loop paths) but sometimes it helps to think of them that way, especially when first learning about them.  Once you get to a point, as an engineer or physicist, to require a deeper understanding of subatomic structure, however, you need to know quantum theory, and that is not much like a solar system at all.

The trouble with using these comparisons, you see, is noticing when you have fallen off the bridge.  If the bridge were a real thing, instead of a metaphor, it would be obvious.  You’d be falling, or submerged in water, or smashed to a pulp.  But, as this bridge is metaphorical, it can be more like a wrong turn, which seems to be making progress towards your goal, but which is really taking you somewhere you didn’t intend to go.

Many years ago, for example, scientists thought that light was a wave.  This caused them to posit a material through which the wave traveled.  They called it “ether.”  Why did they think ether existed?  Well, the waves they knew about all had some substance through which the wave transmitted itself.  Waves in the ocean have, at their basis, water.  Without the water, there is no wave, so clearly light – because it was a wave – must have some “stuff” in which to carry itself. 

Of course, ultimately, scientists proved this was nottrue.  They had been using the metaphor of a fluid wave, and it had led them down an incorrect path.  Light might have some properties of “physical” waves, but not the requirement to have a transmitting material.

None of the above is meant to discourage anyone from using comparisons!  Far from it!  As I said before, our minds seem to look for similarities, and those similarities help us learn.  My point today is about being aware of the metaphors you are using, so that if you need a more thorough understanding of something, you can use more than the model. 

Of course, even when you do, you’re probably going to just encounter another model – those scientists who care about electrons need to understand mathematical probability – because true understanding of many topics might just be beyond what you need, or what we can accomplish.  But if an additional metaphor helps you comprehend the thing more completely, then, by all means, use it!  Just be aware, it’s still just a model.

==========================================


[I have been wanting to write about this topic for well over a year, but I’ve been avoiding it because I feel it’s very expansive, which makes it hard to cover properly in a blog, which I feel is a medium typically more conducive to taking a concise approach.  So, what changed my mind?  Well, I recently bought another Great Course, and as I looked at the list of lectures, it appears I will be hearing 30 minutes on this very topic.  I decided that I want to get my thoughts captured before being exposed to those of the professor.  I will be happy to revisit the whole idea later.  Meanwhile, I remain abashed proud of the silly pun in the title.  So I like Star Wars; so sue me. ]

2 comments:

Larry Bolhuis said...

Oh go take a long walk on a short Bridge!!

Buck said...

Wittgenstein has some interesting thoughts on language and shared experience. When you and I have a common framework, a simple phrase like "MacArthur on the beach" conveys many things despite the spare word count. Promises kept, vows fulfilled, inevitable victory, we make our own fate...

Without a shared framework, something that says a LOT to me may be quite incomprehensible to you, despite common English words: "The new East Coast distance record for 78GHz is over 125km!" The words seem clear enough, but where's the emotional content? Meh, am, I right?

Metaphor helps to establish a shared context between speaker and listener, writer and reader. No communication is perfect, but having a common framework helps.