DESCARTES, René (1596-1650). Opuscula posthuma, physica et mathematica. Amsterdam: P. & J. Blaeu, 1701.

First edition of a collection of posthumously published tracts, including the first printing of Descartes’ Regulae ad directionem ingenii, his first writing on the “method of doubt” and the precursor of the Discours.

His “first substantial work was the never-completed treatise Regulae ad directionem ingenii (‘Rules for the direction of the mind’), which was written in 1628 or 1629 but was not printed until 1701. The Regulae reveals that Descartes was already preoccupied with method as the clue to scientific advance – a method of basically mathematical inspiration, though it is intended to be the method of rational inquiry into any subject matter whatsoever. This concern with method appears in the Regulae in a form that is both more detailed and less metaphysically committed than the form that appears in Descartes’ later philosophical works” (Bernard Williams in Encyclopedia of philosophy).

The other tracts in the Opuscula are: I. Mundus, sive dissertatio de lumine, the first Latin edition of Le monde, in a textually more accurate form than the French edition published in 1664. Written shortly after 1630, Descartes withdrew this work from publication as a result of the condemnation of Galileo. II. & III. De mechanica tractatus una cum elucidationibus N. Poissonii, first edition of Descartes' original Latin text, with commentary by Nicolas Poisson. IV. Primae cogitationes circa generationem animalium, Descartes’ treatise on embryology. V. Excerpta ex mss., comprising various mathematical writings.

The contemporary owner of this volume was M. Bellanger, Treasurer General of the Seal. His substantial library was auctioned in the year of his death and numbered almost 4,000 lots, including a number by Descartes, although this Opuscula does not appear. The catalogue introduction describes the majority of the bindings as in morocco or gilt calf, the work of Royal Binder Boyer. Guibert p.221.

Quarto (201 x 150mm). Numerous woodcut diagrams and illustrations, woodcut printer’s device on title, headpieces, and initials. Contemporary sprinkled calf, gilt Bellanger arms [Oliver 1867] on sides, gilt spine with red morocco spine label lettered in gilt, red edges (light wear at extremities, upper hinge splitting). Provenance: M. Bellanger, Treasurer General of the Seal (d.1740; binding).