I've never thought to group my special interests into categories like that, so it would be hard to say in my case. I don't think I could categorize them. When I'm obsessed with something, it's usually all-encompassing. For example, my main interest last year was radio. Indulging in it could entail anything. Listening to the radio, reading about radio science or its history, looking at radios, taking them apart, organizing parts, sketching and labeling them. Even watching shows where the characters used radio in some form was satisfactory (to be honest, I derive great pleasure just from typing or saying the word "radio"). I could go on and on. But the point is, I couldn't limit radio to a historical, scientific, or cultural interest, etc. It was just radio. Well, maybe it could be called a technological interest. It would be my only one, though, so I'd have to say that I only have unique interests. Horses, radio, the Confederacy, a random person who used to live in my town...Yeah, I can't see any connections.
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I have not the kind affections of a pigeon. - Ralph Waldo Emerson