Debra and I had some friends over for dinner this evening. We got to talking about my bicycle training and I mentioned that I’d lost over 10 pounds since October. It seems like whenever somebody mentions losing weight, somebody else will say something to the effect of “You didn’t lose it. You gave it to me!” As always, my brain analyzed that comment from several viewpoints and came up with an odd idea: the aggregate weight of the Earth’s human population is constant. I know it’s absurd. But it was fun to toss around for a bit.