 Descartes employs the method of analysis in Meditations (Second Replies, AT 7: 155–156, CSM 2: 110–111). In metaphysics, the method of analysis “shows how the thing in question was discovered” (ibid.). Descartes opposes analysis to synthesis, in which first principles are not discovered, but rather given in the form of definitions, postulates, axioms, theorems, and problems (ibid.), as in a Euclidean demonstrations. Synthesis “cannot so conveniently be applied to […] metaphysical subjects”, Descartes writes. Why? 