Cedric Chin, (Chin 2020)


YouTube, and video in general, is a wealth of tacit knowledge. Seek out a combination of instructional and videos where an expert is doing the thing you’re learning.



A couple months ago, Samo Burja wrote an essay on Medium titled The Youtube Revolution in Knowledge Transfer (a), a piece that I loved and linked to in issue 50 (a) of the Commonplace newsletter. Burja observed the following things:

  • First, YouTube is now a thing.
  • Second, quality digital cameras have become cheap enough for mass use. This in turn means that everyone can start producing YouTube-worthy content, and have those videos be discoverable, because — hey! — YouTube is now a thing.
  • Three, this also means that people with expertise in thing X can now film themselves doing thing X, and clued-in practitioners can watch these experts do thing X and become really good themselves.
  • Burja then posits that we’ll see an explosion of tacit skill transfer over the next decade, correlated with the rise of YouTube use, because certain kinds of human expertise may only really be taught through emulation, not through instruction alone.

YouTube use in Judo

What Oon is more interested in is analysis of competition footage. I asked him to explain how he used video for this purpose, and he did (a):

Let’s say you want to learn how a particular player does a particular technique. Here are some best practices:

  1. Don’t just watch just one or two examples of that player doing that technique. Watch multiple examples and try to identify trends or things that that player does in setting up the throw. Take for example, Takato’s unique style of ouchi-gari. If you watch enough of them, you’ll notice he only does this technique under very specific circumstances (against left-handers who are trying to push his head down). If you notice that, try to understand the reason why.
  2. Pay particular attention to grips. How does he grip whenever he wants to do this technique. You will notice a familiar pattern to the gripping. Again, try to understand why.
  3. There will be times when the technique fails. Watch those as well and try to understand what went wrong. What was different about this attempt that caused it to fail? Doing this will allow you to isolate the key success factors.
  4. Try to look out for variations. Sometimes those differences are very subtle but they are significant. Understanding the variations (when they are used and why the variation are necessary) will give you a better grasp of the technique.
  5. It is usually helpful to watch the technique in slow motion. If there is no slow motion replay of the clip available, you may have to download the clip and slow-mo it yourself using a simple video editing program. When I was a student there was no digital videos yet, only VHS cassettes, and I had to use two VCR machines to make slow motion loops of Koga’s throws just so I could study them properly!

In a separate interview with US Olympic silver medallist Travis Stevens, Oon asks about video, and Stevens answers (a):

There is a lot the cadets can do at home to prepare them for future success. Like learning how to break down a fight when watching videos, taking notes on training sessions (emphasis mine), journaling, etc. Winning at judo isn’t just about hard work. There’s a lot more that goes into it than that, like analysis, mental training and so on.

Why study competition footage, and not just instructionals? The answer falls out of everything we’ve explored in our previous posts on tacit knowledge. Expertise is difficult to explicate, and embodied knowledge can only loosely be captured through language. There usually isn’t much of an overlap between the greatest practitioners and the greatest teachers in any given domain.

So the solution here is to do what Oon figured out all those years ago: don’t wait for someone to come along and explain what’s going on. Don’t rely on instructionals alone. Look at actual experts doing the actual thing. In the context of Judo, this means developing the meta-skill of watching competition video yourself, in order to break a competitor’s technique down into its constituent parts. You try to figure out why it’s so effective; later, in the dojo, you attempt to replicate it by copying.

In fact, as we’ll soon see: this principle is generalisable. When you want to learn a skill on YouTube, you should spend a little bit of time watching instructionals, but then spend the rest of it watching experts doing the actual thing. The former is by definition explicit; the latter allows you to capture what is tacit.


In fact, there’s a good rule of thumb here that I think is worth keeping in mind: if something can fit into the length of a typical programming conference talk, the odds are good that the aforementioned thing is easily explicable. You get the sense that Hickey’s talk could not fit into the length of a conference keynote; if you gave him more time, he could go on.

You get this feeling because Hickey is trying to communicate something deeply tacit: a principle that he has imbued into all the projects he’s worked on from Clojure to Datomic. And indeed, the more common programming conf talks tend not be like Hickey’s; they tend to be about easily explicable topics like ‘how to use cool new feature in programming language X’ or ‘how to do technique Z in framework Y’; you’re not likely to get higher level things like “how do I structure a program to thread the thin line between too much abstraction and too little?” or “how do I evaluate the risks of my client being an idiot, which means we’ll have to redesign a whole subsystem a month from now?” That sort of thing is tacit, you pick it up while on the job, working alongside more experienced people.

So if conference talks and lectures are the programming equivalent of Judo instructionals, what is the equivalent of analysing competition videos? The answer, of course, is coding livestreams.

Wrapping up

In fact, I haven’t tried this yet, but I want to know if Oon Yeoh’s principles for analysing Judo video generalises to every other domain of tacit knowledge. If we take his list and remove the Judo-specific references, we get:

  1. Don’t just watch one or two examples of the expert doing a technique. Gather multiple examples and try to identify trends or commonalities in the usage of their technique. When you notice such commonalities, try and understand why those commonalities exist.
  2. Pay particular attention to context. What happens before or after application of the technique?
  3. There will be times when the technique fails. Watch those as well and try to understand what went wrong.
  4. Try and look out for variations. These variations represent changes in the action script associated with the prototype in the expert’s head. Sometimes these differences are very subtle, but they are significant. Understanding the variations will give you a better grasp of the technique.
  5. It is usually helpful to watch the technique in slow motion. Download the clip and slo-mo it yourself using a free video editing program.


Chin, Cedric. 2020. “How to Use YouTube to Learn Tacit Knowledge.” Commoncog. https://commoncog.com/youtube-learn-tacit-knowledge/.