PREFACE

in many others, one remains in uncertainty. On the other hand, was the manuscript in Descartes' own hand, or had he prepared fair copies original: "expéditions au net"; clean, final versions of a manuscript intended for a printer. for the printer through one or several copyists, who might have introduced, more or less accidentally, forms of their own spelling instead of Descartes'? At least for the Dioptrics, the copy was by a specific hand. Indeed, in this treatise, as given in the 1637 edition, the form ceste An archaic spelling of "cette" (this/that). predominates, whereas in other parts of the work, this form does not appear at all, and one sees the forms cette and cete alternating irregularly—the latter alone being authentically Cartesian, as his own handwriting absolutely excludes the other two.

Faced with these difficulties, we could not, however, bring ourselves to overload the bottom of the pages with purely orthographic Relating to spelling and the physical way words are written. variants. This was of no interest, since those we provided in the volumes of the Correspondence constitute a body of material more than sufficient for study.

We therefore agreed, first of all, to silently correct obvious printing errors as well as grammatical oversights (singular for plural, feminine for masculine, or vice versa), which likely already tainted the copy. We had no more hesitation regarding inaccuracies of the same kind in the algebraic formulas of the Geometry.

Secondly, we have tried to regularize the punctuation according to the sense, while avoiding systematic modernization, which is, moreover, incompatible with the structure of Descartes' sentences. Furthermore, we have conformed the accentuation to the philosopher's well-established usage¹.

1. I must add, however, that for ease of reading, I have consistently printed où original: "où"; the French word for "where"., as an adverb, in the three Essays, whereas Descartes' most frequent usage is to omit the accent, just as he does for the conjunction Descartes often wrote "ou" for both "or" (the conjunction) and "where" (the adverb).. The same applies to là original: "là"; the French word for "there"., as an adverb; on the other hand, for à original: "à"; the French word for "to"., as a preposition, the omission of the accent never leads to hesitation. (T.) Likely referring to the editor Paul Tannery.