Experts (Usually) Make Terrible Teachers


Experts spend years of effort learning, researching, experimenting, and coalescing knowledge. They've persevered when others have given up, gotten bored, or moved on. They have intimate knowledge in their field, acting as an authority to give advice, make key decisions, and push their respective field further.

So why is it that so many of them can't teach?

If your higher education experience was anything like mine, you had at least of these professors. I had several. The nearing retirement tenured professor that has taken precious time from their day to regurgitate information in a unstructured stream of conscious. The guy that literally wrote the book in his field, and will show it by quoting verbatim at length. The frizzle haired researcher, downing her ninth cup of coffee and she tornadoes through the lecture to get in, get out, and get back to the lab.

There is little doubt in your mind while sitting through these lectures that this isn't an expert, that they don't have something valuable to give to us. But when the lecture is over, you look to your neighbor, shrug, and just hope there is some quality YouTube material out there to fill in the gaps.

This is common. It may even be expected if you ask a neuroscientist.

In his book, How We Learn, Why Brains Learn Better Than Any Machine...for Now, Stanislas Dehaene goes into detail on the neural structure of knowledge. Knowledge is comprised of an internal hierarchy or rules that the brain tries to infer when input data is consumed. It is a complex web of abstract and concrete algorithms used to parse the inputs of our body.

With an expert, these neural algorithms have been built and refined over years. Each new experiment has altered these algorithms, some have broken links and formed new ones with different algorithms, while others have reinforced the previously earned knowledge, strengthening the existing bonds.

The problem with experts is that they have built, rebuilt, and modified their internal models of knowledge so much, the difference between what you know and what they know is a vast chasm that seems impossible to cross. The days of the expert being lost and confused are so far gone in their history, they don't know hat it's like anymore.

To an expert, teaching the basics of their subject is the equivalent of you or me teaching a baby how to walk.

"You first need to stand up. Hrm, how do you teach standing? Ok push your body into this upright position. Use a table or wall. Now pick up one foot, but don't lose balance! What is balance? Uhhh, it's not falling over. You know how to do that now, right? Then you put that foot down, but further away from you. You'll want to kind of fall into that foot with your balance. Don't worry, you'll catch yourse....and you're down. Don't cry. Don't cry. Don't cry."

As an upright walking human, we have internalized the algorithms of balance, gravity, spatial awareness, and limb extension, among many other core building blocks of a skill we don't even think about any more.

To an expert, their subject has become the equivalent of walking. They don't know how to explain it.

In order for the student and the teacher to bridge their knowledge chasm, they must establish a shared mental model of knowledge to facilitate communication. This is done by zooming into the core concept of what you're trying to teach, establishing a shared knowledge starting point, and building up that mental model piece by piece. Teaching incorporates testing scenarios, evaluating successes and failures, building new hypotheses, and repeating the cycle. Our brains are constantly acting like little scientists, pushing their knowledge with observation and experimentation. It is the duty of the teacher to observe the learning path the student is taking, and guide them down the correct path.

So what can be done to bridge this knowledge gap as an expert?

Bury away your assumptions

Work to establish the common ground you share with the students. Age, experience, willingness to learn, and the complexity of the subject matter will dictate how far back you need to go. When in doubt, check in.

Before I start on this. Do you know about x, y, and z and how they relate together?
Ok let's start with x and work our way up.

Direct the attention of the students

Don't allow students to go down the wrong path for too long. Experimentation and failure is a key component of learning, but multiple successive failures and lost time can be discouraging and lead to drop outs. Guide them down the path of success without too many detours.

Encourage new hypotheses

Ask questions that require the student to make one leap. Don't ask the questions that require six leaps. Get them to eliminate the dead ends, focus on what their gut is telling them; it's an internal model that is trying to give an answer. Help them push their limit on their own with small challenges that generate success and can be build on each other.

Provide timely error feedback

Redirect when a student goes down the wrong path for too long. Ask the student what their thought process was to get to this failure. Help them work backwards to where their assumptions where correct and show them the path that forks off to success.

Allow time for consolidation and internalization

Burying a student with information will ensure that the student only retains a small piece of it. You have to allow time for the brain to shift memories from short term to long term memory. This is done with sleep, and only so much information can be shifted per night.

As a student, what can you do when your in class with one of these experts?

Ask questions early

Before the teacher goes too far off in their thoughts, bring them back to the common model. Make it clear what you know. Don't focus on what you don't. You don't know what you don't know. Interrupt their pattern of skipping steps and making leaps. Force them to walk you through it. Your other students will appreciate it.

Conduct your own experiments

When you hear something that lights a fuse in your brain, give yourself the moment to think of the "What Ifs?". This is your brain building an experiment that it wants to test. Depending on the outcome, your brain will internalize this information. Some of these experiments can be answered internally, but don't be afraid to reach out and ask. If the teacher promises an answer in the future, trust their process, write your thought down, and circle back at a later point.

Sleep and rest

Sleep is the best thing you can do for your learning journey. Allow your brain the time it needs to take this new information and create the neural links with your existing mental model. Everything you know is linked together. Your brain knows how to build these links. It just needs you to stop giving it new information for long enough for it to catch up and build these new links.

Find a non-expert that has knowledge

Sometimes the gap may still be too large. This may mean you just need to shrink the gap with another teacher. The people that have followed a similar path to you, but are a bit further along can be a valuable resource to help provide clarity. The distance between your shared knowledge model is smaller, so your assumptions and hypotheses will be more closely aligned. See if you can filter what you were told by they expert through the non-expert. They will often know was missing from the expert's explanation and be able to fill in the gaps. Their experiments are fresher in their minds, and can be passed along to you to help you build your model.

I'm always excited when I have an opportunity to pick the brain of an expert. It provides an opportunity to make great leaps in knowledge. I just have to know where we share our common knowledge and build a conversation on shrinking that knowledge gap. At worst, I get a whole list of new topics to research, and some new experimental questions to task.

Thank you experts for what you do. Just maybe slow down a bit, the rest of us are still trying to walk.