Since 2013, the Nonhuman Rights Project has been working on behalf of two chimpanzees, Kiko and Tommy, to have them declared eligible for basic rights—the same as if they were a “person.” Under current United States law, one is either a “person” or a “thing.” There is no third category. The philosophers admit that the idea of “nonhuman personhood” seems confusing, as we tend to use the two terms synonymously and interchangeably.