Abstract
The 2006 decision by the International Astronomical Union to strip Pluto of its status as a planet generated considerable uproar not only in scientific circles, but among the lay public as well. After all, how can a vote by 424 scientists in a conference room in Prague undermine what every well-educated second grader knows is a scientific fact? The Pluto controversy provides a new and fertile ground in which to revisit the traditional philosophical problems of natural kinds and scientific change. Before engaging these philosophical problems, however, there are two misguided reactions to the Pluto controversy worth dispelling from the start. The first misguided reaction is that this sort of classificatory ..