L. J. Beck. The Method of Descartes: A Study of the Regulae. Clarendon Press. 1952. 316pp.

Excerpt:

Nowhere in his writings has Descartes given a more lucid and emphatic account of his conception of philosophy than in the “author’s letter to the translator” which serves as preface to the French translation of the Principia Philosophiae, a preface which has been aptly described as a manifesto against the philosophy of the Schoolmen.  This conception presupposes explicitly as its logical basis the fundamental Cartesian principle of the unity of all science or human knowledge. “Aristotelian scholastics held that the certainty of mathematics, deriving from its purely formal character, was unattainable in sciences having concrete existents for their data, and the method of each science should answer to, and vary with, difference in the materials it investigated.”  The Cartesian plan, revolutionary in its time, was to demonstrate that the different sciences were but parts of a single science, in the metaphor of the preface to the Principia, branches of the same tree.

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