What Tacit Knowledge Costs

There is a difference between explicit knowledge and tacit knowledge. Explicit knowledge can be written down. You can put it in a manual, a memo, a book. Tacit knowledge is the rest. It is the kind that lives in a person's hands, or judgment, or intuition. It is the kind that cannot survive the person who holds it, unless someone makes a deliberate effort to pull it out before it disappears.

Michael Polanyi, the philosopher who named this distinction, described it simply: we know more than we can tell. This is true of every person who has done anything for long enough. The surgeon who can feel whether a repair will hold. The teacher who reads a student's confusion before the student knows they are confused. The manager who can tell, from the first five minutes of a meeting, whether a project is on track. None of these skills were acquired from a textbook. All of them are irreplaceable.

We do not value tacit knowledge because we cannot quantify it. We cannot put it on a resume in a way that means anything. We cannot train it out of a curriculum. So we treat it as invisible. As background. As a bonus that some people happen to have and others do not. This is an enormous mistake.

Tacit knowledge is the most expensive knowledge there is. It costs years to acquire. It costs repetition and failure and the slow accumulation of things that only make sense once you have seen them enough times. And when the person who holds it dies or leaves or retires, the people around them pay the full price of that knowledge again from scratch. Someone starts over at zero. The organization, or the family, or the community, absorbs the cost of re-learning what one person already knew.

The question is not whether tacit knowledge can be fully transferred. It cannot. Some of it is irreducibly personal. It is bound up with who a person is, how they see the world, what they have been through. You cannot download it. But a surprising amount of it can be captured, if someone is willing to try. Not the conclusions, which are easy. The conclusions are already visible. What can be captured is the reasoning behind the conclusions. The things a person noticed. The things they weighted differently than other people did. The questions they asked that no one else thought to ask.

Most people do not try because they do not think anyone would be interested. They assume their experience is ordinary. They assume their reasoning is common sense. They are almost always wrong about both. The people who come after them are deeply interested in exactly these things. Not in what their parent or mentor accomplished, which is already on the record. In how they actually thought. What they saw that others missed. Why they made the choices they made when those choices were not obvious.

Every year that passes without capturing this knowledge is a year of cost that someone else will pay. Every person who dies or retires or walks away without documenting their reasoning is creating a debt that falls on the people who follow. The 135 is about refusing to do that. About deciding that the cost should stop with you, and the knowledge should not.