• Descartes’ Discourse on Method, originally a sort of preface to a group of his scientific works, is partly autobiographical, and the selection we’ll discuss (pp. 19-21) comes from a part of it where he describes a work that he never published in which he’d offered a hypothetical description of the natural world. The bulk of this selection, as well as the two selections from letters that follow it (pp. 21-25), concern his view of the difference between animals and people.

• The selections from Descartes’ Meditations, his best known philosophical work, comes from its last part. In the first of these selections (pp. 25-27), he recalls things he has discussed earlier in the book and then offers his central argument for difference between mind and body. Because he views the two as fundamentally different substances, it is not obvious that the mind could even know of the body’s existence, and the second selection (pp. 28-30) is part of his argument that it does. In the part of the argument in this selection, he is considering a subsidiary problem, which he poses at its beginning, and his way of solving this problem leads him to describe in some detail the relation between the mind and body.