Who Shaved the Barber?

For years, I've read in various places the above question. I knew it had something to do with logic, but I was unclear on the details. It wasn't until today I realized I had this great big research tool sitting in front of me that I could use to learn more about it.

So, I went to my favorite search engine and typed in the question. The first listing was for a gay men's scrotum shaving page. I assumed that wasn't what I was looking for and moved down the list. Finally, I found the explanation, which I will now bore you with.

Living in one particular town is a barber. Every man in this town either shaves his own beard or has the barber shave it for him. The barber, he only shaves the beards of those who do not shave themselves. So, who shaves the barber?

This little ditty was apparently formulated by Bertrand Russell. The answer is that it is impossible for the barber to stay within the rules and still get shaved. He is a man who lives in the town. He only shaves those who don't shave themselves. Therefore, he can only shave himself if he doesn't shave himself.

There are lots of little details that are required to constrain the barber from taking a blade to himself. He must be male. He must live in the town. There must be a firm dividing line between self-shavers and barber-shavers, with no overlap. Everyone must shave. Possibly more. Forget one detail, and you leave a loophole for the barber to skin himself through. Get them all right, and you have yourself a lovely little paradox, which was the point to begin with.

I feel better for knowing this. Don't you?