What does tagging do to knowledge?

Back when David Weinberger's Everything is Miscellaneous was published, LibraryThing ordered a box of copies to give out at conferences and so forth. (Although LibraryThing is mentioned only in passing, the book is, in a way, the intellectual justification for much of what we do.)

We ended up with a dozen or so left over, so I held a contest to get rid of them: Say something about what tagging means, or what it "does" to knowledge, and you might win a copy. I figured that it was time to stop pontificating about what people were doing with tags, and get them to pontificate instead.

The Talk topic eventually accumulated 170 comments, almost all interesting and some quite lengthy and involved. I found it thrilling stuff. We picked ten random winners, and sent out the books.

The whole discussion is newly relevant in light of our new Tag Mirror feature, discussed on the main blog and at in great detail on Talk.

Here are some selections from the full discussion:

I think the most interesting aspects of tagging, in a social networking context, are that: (1) All tagging is personal and (2) All tagging is public (ssd7)

So what does tagging do to knowledge? It classifies it in a fuzzy, family-resemblance kind of way, doing justice to multiple topics and interdisciplinary books in a way that the Dewey Decimal System could only do if it worked in four or five dimensions at once. (MyopicBookworm)

I like fun tags that are so personal or unique that nobody else uses them. A friend of mine, for example, has tags like "Detectives with gimmicks", "Elaborate crimes", "Witty people being clever", and my favorite "Fangirlin'". I myself want to use a tag for "Farm boys with magical destinies" but it's apparently too long. (saturnine13)

Tags capture individual perceptions of a work, data, and add that information to our knowledge of the work. That's a useful enhancement, but the variety offered becomes a disadvantage if they are used to find other works. Tags lack the precoordination necessary for efficient comprehensive searching. For example, the tagmash search for libraries, --fiction includes libraries and bibliotecas, but not bibliothéques, etc. Related works may have been lost. That interferes with one of Ranganathan's laws—it does not save the time of the reader. (notelinks)

One of the things I find most fascinating about tagging is what it reveals about the cognitive processes of the taggers. What makes one person tag Walden with "simplicity" and another person with "hermits"? It's not a novel observation that we all experience books (for example) personally or subjectively. Tagging is a very simple way to turn that individual experience into universal information. (johnascott)

I'm always amazed at the different ways of viewing something when I see how differently others tagged something to which I have already assigned the most 'correct' or 'appropriate' tags. (bobngail)

Believe it or not, tags are actually more formal or structured than some similar systems. Consider the general WikiWiki idea of turning any word into a link if it's in FunnyCaps. The effect is very similar, but the links appear anywhere in text. Tags isolate the linking to specific fields. The extreme free-form nature of Wikis drives some people off, just as the extreme formalisms of MARC, etc. do. So tags seem to be a widely accepted compromise. (JasonRiedy)

Tagging doesn't so much affect knowledge as reveal it in unexpected places and from unexpected sources. We are all bent, but we're bent in different directions, and so the sum of our deviances converges on reality quickly - and tagging taps into that. (xaglen)

I think the main point to remember is that tagging is NOT JUST an unstructured form of subject headings; it is a completely different way of viewing the world. Taxonomies and standardised subject heading vocab divide knowledge hierarchically according to set rules. Folksonomies allow knowledge to emerge through collaborative involvement. Tagging allows people to look at books in new ways, to share that knowledge, and to create tag clouds so that no one tag gets missed. (mrsradcliffe)

Tagging helps to both aggregate and splinter knowledge. By this I mean, tagging helps to navigate relationships among disparate "knowledge objects" while at the same time, splits the categorization of similar objects into much finer and/or more random collections. (stoberg)

Everything is Miscellaneous is one of 37 books I currently have tagged "included in the present classification" (there are none that look like flies from a great distance). (sabreuse)

First, tags really only seem to work for organizing stuff you have some sort of conceptual "ownership" of things that in some way you have an incentive to keep order within. People don't seem to want to tag in enough quantity / detail to be useful when they don't have a personal stake in sorting through the resultant mess. (cubeshelves)

I much rather spend my time reading a book! (bcobb)

From a library standpoint, my favorite thing about tags is that it allows natural language into the catalog. .. [A]nd what tagging does to knowledge? It gives you more access points. (e1da)

Tagging is getting awfully close, it seems, to the way our brains naturally work anyway - it "associates" and "retrieves" based on miscellaneous tags it has (subconsciously) attached to the idea or concept. (nicknich3)

The variety of tagging systems is amazing. You can tell a lot about a user’s interests by the complexity of tags relating to a specific concept. I am always a bit disappointed when I encounter a catalog without tags. Of course you can look at the books in that catalog, but you don’t get much indication of the user’s relationship to their books. (oregonobsessionz)

[SilentInAWay wrote an exceptional piece on the Deathly Hallows tag cloud and it's common and uncommon tags, from fantasy (783) to Kleenex (1): — Ed]

[W]here there is a clear consensus on a tag, it is probably based on fairly broad considerations (and therefore constitutes relatively superficial knowledge). Conversely, the most intriguing tags (autistic-like character, Kleenex, the end of Pottermania) are almost inevitably used by only a single member. (SilentInAWay)

I remember being flabbergasted when I found out how long it took for the Library of Congress to change the subject heading "Vietnam Conflict" to "Vietnam War." Now it doesn't seem so ludicrous to me.

Even recognizing that LC Subject Headings and tagging achieve two different goals doesn't ease my mind about this. I cannot stand the thought of how muddy and increasingly useless much of Library Thing's tagging database will end up being in a very short time. (lmccoll)

Tagging permits me to see books as others see them. (kencf)