Why learn something that isn’t true?

As we progress in school, the lessons get more difficult and complicated.  Sometimes they’re difficult because we have to unlearn things.

Our chief consultant writes:

For our consultants, it normally happened about the first year of college.  They took up again sciences they’d learned in High School, notably chemistry and physics, but at a higher level.  And sooner or later a student would exclaim, “They lied to us!”  What usually prompted the outburst was the discovery that situations weren’t actually as simple as the earlier textbooks had them.  Ball-and-stick models of molecules turned out to be inadequate; frictionless surfaces weren’t; simple harmonic motion wasn’t so simple.

The discovery that life is complicated is a part of reaching adulthood and is always at least somewhat painful.  But this was particularly galling to our consultants, who thought they understood chemistry, or physics.  (Mathematics was less of a problem, since the new complexities of calculus were built on algebra and geometry, rather than replacing them.)  Unlearning and relearning requires some concentrated effort.

So why not include all the complexity at the outset, and avoid the complications of unlearning?

In large part, it’s because it leads to a very ineffective way of teaching.  In our library we have some books of grammar, setting out the system of a language in organized form, all the complexity there at hand.  It’s almost impossible to learn from them.  Language teachers found out long ago that students learn best by starting with simplified sentences and gradually adding complications.  The Feynman Lectures on Physics attempted something of the sort by including some pretty advanced material in a first-year physics course, and Richard Feynman himself thought that part didn’t work.

In part, it’s because one would have to wait until the student had mastered advanced partial differential equations (about the junior year of college) before beginning the study of chemistry, which is largely built upon quantum mechanics.  That’s much too late to make much progress as an undergraduate.  And, as we’ve noted, knowing mathematics to that level is simply not necessary for carrying out much of the work of a chemist.

So from a teaching and a learning standpoint beginning with simplified situations is the more effective way to go, even if it requires unlearning and relearning later on.  But we meet with a certain irony: a simple situation can be very difficult to arrange.  Air friction disturbs the motion of all objects, so that none actually follows the perfect parabola of innumerable physics problems.  Even the best springs have some energy losses, so the masses stop bobbing up and down as we watch.  A chemistry experiment designed to demonstrate the conservation of mass is bedeviled with many ways to go wrong, so that (in another irony) it takes a fairly well-developed skill in the lab to show this beginning-chemistry idea convincingly.

Beginning with the simple and adding complication can be difficult in several ways, but it’s the most effective way of learning that we have.  So far.