Tacit knowledge follow-up

15 Apr, 2026

Here is Matt Glassman replying to my recent note about tacit knowledge.

A few more notes:

1. A while ago, there was a lot of discussion about how YouTube and related tools allow for wider transmission of previously less-transmissible knowledge, with the (amazing!) focal example of Julius Yego, an Olympic silver medalist in the javelin who learned from YouTube. Now, tacit knowledge is not identical to knowledge the transmission of which is uniquely enabled by video, but there's a lot of overlap.
2. In programming, at least, an embarrassing amount of expertise is just knowing what exists: tools, common failure modes and useful patterns, and so on. Yes, you need enough comprehensive understanding to apply these properly, but a lot of talking to an expert is just hearing "oh, there's a good tool for that."¹
3. In problem-solving and game-playing contexts, I suspect that a primary function of tacit knowledge is to decompose problems. It happens all the time in poker discussions that an expert will say "well, the range at point X has to be approximately Y," and this makes the rest of the problem tractable (e.g., by allowing you to use simple logic and arithmetic to get from Y to a river range). Importantly, experts have all sorts of ways of knowing or intuiting that initial X - Y relationship. You could characterize a lot of small- and mid-stakes poker as the quest to find information that's reliable enough to let you turn huge, complicated poker problems into simple ones.
4. It's tempting to think that YouTube exemplifies how we're getting better at transmitting tacit knowledge, but I'm not sure we are. I suspect that direct face-to-face interaction and certain kinds of leisure and diversity of experience are very important to building and transmitting tacit knowledge; at least some versions of those are arguably declining. Here is an amazing Terence Tao note about the value of semi-random inputs to creativity and knowledge-building.
5. One of the most memorable passages in Pat Conroy's My Losing Season is his description of his coach (Mel Thompson)'s amazing basketball know-how, largely intact after decades of retirement as a player, and its contrast with Thompson's limitations as a coach.