Tacit Knowledge

Tacit knowledge or implicit knowledge is knowledge that is difficult to extract or articulate—as opposed to conceptualized, formalized, codified, or explicit knowledge—and is therefore more difficult to convey to others through verbalization or writing. Examples of this include individual wisdom, experience, insight, motor skill, and intuition.[1] An example of "explicit" information that can be recorded, conveyed, and understood by the recipient is the knowledge that London is in the United Kingdom. Speaking a language, riding a bicycle, kneading dough, playing an instrument, or designing and operating sophisticated machinery, on the other hand, all require a variety of knowledge that is difficult or impossible to transfer to other people and is not always known "explicitly," even by skilled practitioners. The concept of tacit knowing comes from scientist and philosopher Michael Polanyi. It is important to note that he wrote about a process (hence Tacit Knowing) and not a form of knowledge. However, his phrase has been taken up to name a form of knowledge that is apparently wholly or partly inexplicable...as opposed to formal, codified or explicit knowledge. http://en.wikipedia.org/wiki/Tacit_knowledge

Tacit knowledge consists often of habits and culture that we do not recognize in ourselves (Legibility)

cannot be codified, but can only be transmitted via training or gained through personal experience (Master And Apprentices)

Steve Denning applies it to Story Telling.

The classic John Seely Brown story about Xerox copy-machine repairmen and their annotated manuals covers this area. (1995-11-30) Brown The People Are The Company

Here's a case of lost knowledge needing to be re-created: maybe engineering archaeology will always exist. The more I look around, the more the engineering world, once you go back more than a few years, looks like subterranean New York City. A mass of strange engineering feats humming away out of sight, produced by long-forgotten ancient peoples, leaving only fragmentary maps and diagrams.