Translator's preface

Descartes' Rules for the Direction of the Mind (Regulae ad Directionem Ingenii) was written in Latin, probably in 1628 or a few years earlier, but was not published during the author's lifetime. A Dutch translation of the work appeared in Holland in 1684, and the first Latin edition was published in Amsterdam by P. and J. Blaeu in 1701.

In the inventory of Descartes' papers made at Stockholm shortly after his death in 1650 the work is listed as ‘Nine notebooks bound together, containing part of a Treatise on clear and useful Rules for the Direction of the Mind in the Search for Truth’. The original manuscript, which is lost, passed to Claude Clerselier, one of Descartes' staunchest supporters, who showed the work to several scholars, including Antoine Arnauld. The manuscript was seen also by Adrien Baillet, Descartes' biographer, who gave a summary of its contents in his La Vie de Monsieur Des-Cartes (1691). Leibniz bought a copy of the original manuscript in Amsterdam in 1670, and this copy has survived among the Leibniz papers in the Royal Public Library at Hanover.

The Rules was originally intended to contain three parts, each comprising twelve rules. The second set of twelve rules is incomplete, ending at Rule Twenty-one, and only the headings of Rules Nineteen to Twenty-one are given. The final set of twelve Rules is entirely missing; it appears that Descartes left this project unfinished.