THROUGHOUT the book I will refer to Descartes's works by giving two sets of volume and page numbers. First I will give references to The Philosophical Writings of Descartes, the three-volume English translation by John Cottingham, Robert Stoothoff, Dugald Murdoch, and, for the third volume, Anthony Kenny. A reference to page 12 in volume 2, for example, would read, “2:12.” Second I will give volume and page references to the standard edition of Descartes's works, edited by Charles Adam and Paul Tannery. A reference to page 17 in volume 7, for example, would read, “AT 7:17.” Readers using The Philosophical Writings of Descartes will find volume and page references to Adam and Tannery in its margins. Except where I note otherwise, I give the English translations provided by Cottingham, Stoothoff, Murdoch, and Kenny.
Sometimes for ease of exposition I use letters of the alphabet in expressions that signify what someone thinks, believes, doubts, and so on; and I also use them to signify corresponding sentences. I may say, for example, that the meditator believes that p even though p is false. Strictly speaking this usage is not consistent, but consistency would require clutter and complications that I want to avoid. I hope readers will find that the inconsistency is a reasonable price to pay for smoother exposition.