MY COLLEAGUE, the editor of Democracy in America, sent round an e-mail asking who was going to live-blog tomorrow night's Republican presidential debate. Another colleague replied, idiosyncratically to my eye, "I'm up." (Normally, for me, "I'm up" has to be followed by "...for it" to show willingness.) So I wrote back, "Unlike ____, I'm down", borrowing a little slang from the kids. A third wrote "As for me, I'm in." And a fourth chimed in: "I'll be around." I suppose a fifth might now write "I'm with it," a sixth, "I'm on it," a seventh "I'm aboard."

Prepositions are funny; they are probably used metaphorically much more than they are used in the physical sense of their spatial relations. Children and foreign-language learners learn in as in "The ball is in the box" in their first few weeks, but have to immerse themselves in a culture for a while to know that if they're asked to participate, they might say not only "I'm in" but "I'm down," which means the same thing. Some people want language to behave logically all the time. For me, it's the messy stuff like this that makes it so much fun.