This post is a pretty good link to hang some of my recent thoughts about knowledge on. Here is what I have been thinking: specifically, that all knowledge is tacit. And therefore, that no knowledge is explicit. That what we think of as explicit knowledge - statements of fact, formulas, generalizations, etc. - are at best abstractions that incompletely capture some (salient) aspect of our (much more fine-grained and ineffable) awareness, and are additionally necessarily context-dependent, or relative to the frame or model in which they are expressed, and in which the abstractions (the words and symbols) obtain their meaning. OK, this doesn't really relate to Snowdon's post - but I wanted to get it out there, and it's at least sort of in the same subject area.