From entry tacit knowledge in glossary Artificial Intelligence: humans at the heart of algorithms
Tacit knowledge refers to things we know how to do or say, but don't know that we know. For example, you might walk the same route home everyday, but find it hard to describe to a friend how to go there. This is important in expert systems as much of expert knowledge is tacit, so knowledge elicitation techniques need to externalise this.
Used in Chap. 7: page 102