Over the past few days, a conversation has been progressing in my timeline about the exact definition of an ‘expert’. Sure enough, it quickly evolved into a vehicle for the usual suspects to take potshots at Cognitive Load Theory (CLT). I thought it might, which is why I decided not to get involved. Instead, I am responding with this post.
I don’t much care what the definition of a expert is. When people start arguing about definitions, I tend to switch off. Apparently, Anders Ericsson has suggested some parameters to do with hours of practice. Yet this seems essentially arbitrary. For example, if you know all of your times tables up to 12, are you an ‘expert’ in times tables? In a sense, perhaps you are, but the word doesn’t seem appropriate because it connotes a wider body of knowledge and/or skills developed over a longer time.
We may also make a mistake when we assume people are experts in vicious domains like financial markets. They may talk-the-talk but their predictions could be no better than anyone else’s or the roll of a dice.
What has all this got to do with Cognitive Load Theory? Not much. There is a CLT effect known as the ‘expertise reversal effect’ but ‘expertise’ and ‘expert’ are not synonyms. Expertise is relative and it seems far better to describe someone has having expertise in times tables than it is to talk about them in absolute terms as being a times tables expert. And it is relative expertise that is important in CLT.
For instance, I teach projectile motion as part of a physics course. In order to solve problems involving projectile motion, students need to be able to rearrange equations, but I don’t tend to teach this technique because they generally tend to have this expertise. If anything, I remind them and I point to a few potential pitfalls. Instead, I explicitly teach them key principles, such as the independence of vertical and horizontal motion, and I model solutions by working through examples of problems while explaining my thinking. Later, as student expertise increases, I expect them to solve problems themselves. I don’t simply keep demonstrating solutions. I only do that if students get stuck on a particular problem, or as a reminder.
It is possible that there are teachers out there who continue to explicitly teach something after students have gained sufficient expertise that they would benefit more from practice. However, this is unlikely to stem from a philosophical position and more likely to arise from some kind of misunderstanding. The key axis on which educators differ in this regard is what we might describe as constructivist versus instructivist and it effects how we teach students new content i.e. when they lack any expertise. Constructivists would argue for withholding some guidance whereas instructivists would seek to fully explain concepts from the outset. The evidence from the research related to Cognitive Load Theory suggests that the instructivists have this right.