Not all philosophical work is about important questions. Some of it may seem absurd to non-philosophers. For example, how is the mind connected to the body? Most of us know that if we want to raise our right arm and we are not paralyzed, it is the easiest thing in the world to do—we just decide to do it and the arm goes up. But ever since the work of the seventeenth-century philosopher René Descartes (1596–1650), philosophers have argued passionately among themselves about the right way to describe the connection between the mind and the body.