Knowledge is usually seen as know-that as opposed to the know-how practical capabilities or skills are described as.
But there is a way of describing knowledge that renders both aforementioned species on a par or on the same level. The guiding metaphor or image is that of orienting oneself in a landscape, that ability or knowledge one has when one is accustomed to a spot or region and is, on an intuitive level, able to find one’s way without much fuss.
So let’s have knowledge as one’s ability of orientation in information contexts of a certain (but principally unlimited) complexity And let’s adopt Gregory Bateson’s famous phrase and describe information as the smallest difference that makes a difference. Or to be a bit more precise: the smallest significant difference that makes a difference.
What we have, then, is a concept of information that is not a datum, something given (a fact usually, but a factum is something made, not found, too), but something in between. It is something that appears in the foreground relative to other things in the background. It changes in significance, in value, in duration, all depending on the person or persons involved. That means: Information isn’t something durable, something fixed, but something fluid. That is so because to one person something may be a significant difference that for another person is not, wasn’t ever, or is no more. You get the picture.
A context of information is a context in which information changes, differences appear and vanish relative to the person or persons involved. Knowledge as the ability to orient oneself in those contexts is the ability to register, value, and appreciate the differences in question. So we come to the concepts of knowing-better-than and knowing-worse-than. A specialist knows more about a theme in the sense that he knows — beyond the data – the caveats one has to acknowledge in framing valid assertions. The layman lacks this ability.
Learning becomes the ability to orient oneself in an information-context better than one was able to some time ago. Forgetting becomes the loss of the ability to orient oneself in such an information context one was able to earlier.
These images focus not on data but on differences. On what people do with data, what they mean to them, what amazes them, etc. Differences vary from person to person. The ability to place data and information in their proper relation is akin to the ability to deal with a tool in a craft, the ability to ride bicycle, to play piano, etc. You have to learn it, you can forget it, others may be better than you, and others are not. The ability to place something in the appropriate region of a context, to differentiate, to ponder the significance, to decide what is new and what a mere façon de parler — that is what know-that is about and wherein the mastery of a researcher lies. His ability to recognize when a difference is a significant difference distinguishes him from the layman and what makes his opinion valuable to others. So even on the web the expert doesn’t need to become dumb.  At least not by the amount of and access to data and information, but due to his varying and changing ability of wandering around — and wondering about. But we all grow old, don’t we?
 ∧ This is an allusion to the title of J.P. Rangaswami’s post “Does the web make experts dumb?” as my lines here are a reactions to his deliberations there with which I disagree in the main part. The differences lie primarily in that he seems to see information and knowledge as kind of abstract objects that scientists and librarians tried to lock away from the public for much too long a time in order to gain monetary benefit from this artificial scarcity. In contrast to this caricature I try to remind the reader that knowledge, information, and data are rather distinct topics and results of very different activities. J.P. Rangaswami wrote two follow-ups ( part 2 and part 3 ) to his piece, that were of minor relevance for the post at hand. (Footnote added 2011.06.24)
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