There is a book I want to read called America Unzipped: in Search of Sex and Satisfaction. The book follows the author, Brian Alexander, as he travels across the United States interviewing various "sexual deviants." They are everyone from a priest who gives sex classes to married couples, to an Ivy League-educated porn king, to women at Passion Parties (like Tupperware parties, but with dildos). The book shows that everyone deviates from the "norm" in some way or another.
So if everyone is a deviant, then no one is.
If I had more money (and time) to spare, I'd buy the book in a heartbeat.
In other news, I recently read a news story saying that people who were spanked as children are more likely to enjoy masochistic sex, among a host of other "problems." Which is complete and utter bullshit. Why is masochistic sex a "problem?" It's not interfering with my life, I'm not damaged by it at all, emotionally or physically (besides a few red marks), so what's the big deal? I was spanked only once when I was growing up, and I'll bet that those researchers would never be able to tell by my everyday behavior that I'm in a D/s relationship and that my idea of a romantic evening is getting tied to the heater pipes and spanked with a wooden spoon.
I can't help but wonder, too, whether they're making the fatal flaw of "correlation = causation." Is it possible that there is some personality aspect that predisposes one to enjoying SM, which, when expressed as a child, makes them more likely to be spanked because of it? That is - spanking doesn't cause people to enjoy SM, but some part of their personality both makes them enjoy SM and get spanked as a child.
Even then, that hypothesis is tenuous. Like I said, I was spanked only once. And I know of plenty of other SM devotees that were never spanked as children.