At first, I thought I would go back to all my old posts and tag them (maybe I still will). Then it seemed daunting. Then I worried about being somewhat consistent in my tagging, so that a reader could clearly see that I write a lot about anthropology, or social media. But then I looked at my posts and realized I actually write about a lot of different things. So if I start labeling, do I end up with just a long list of tags? Or do I then feel a need to constrain what I write about to a defined set of categories?
I realize blogs with a theme are powerful...and I think I have some themes running through here...interspersed with random thoughts or items that catch my interest.
What to do? Does it matter? Is there meaning in tags (beyond the meaning I as the tagger ascribe to them)? A goal of semantic web is to provide structure to the web through labeling and tags, and my understanding is that ideally it is supposed to work whether it is my categorization of the world, or yours.
By the way, I am not sure you want to get into my categorization of the world--I am one of those people who knows exactly where a book is on my shelf because it is in a perfectly logical place to me, but you'd probably never figure it out.