Unknown letter of Descartes discovered

Descartes wrote the letter on 27 May 1641 at Endegeest castle, close to Leiden, and addressed it to the French mathematician, theologian and philosopher Marin Mersenne. It is part of an intensive exchange between Descartes and Mersenne in view of the publication of the Meditations. The most important historical information can be found at the end of the letter, where it emerges that originally the book was conceived along different lines. Descartes asks Mersenne to completely eliminate three texts: a Latin translation of Pt 4 of the Discourse on method (originally published in 1637), a preface to that text and to the Meditations, and an introduction to the Objections and Replies. They should be replaced by a new general preface, which corresponds to the preface actually printed. The reason for those changes is that a French visitor has convinced Descartes of the good intentions of the French engineer Pierre Petit, who had been very critical on part 4 of the Discourse — criticism about which Descartes was extremely upset. Now that he knows that Petit changed his mind Descartes has no reason to react to him personally — in the new preface he limits himself to a few general remarks about the criticisms that reached him concerning the Discourse, without naming anybody.

Descartes reacts positively on Gassendi’s criticism

The letter also supplies new information on the relationship between Descartes and the famous philosopher Pierre Gassendi, author of one set of Objections against the Meditations, which Mersenne had sent by the same mail. In later correspondence Descartes has nothing but scorn for Gassendi’s objections — in this letter he shows himself pleased: he likes the style and they provide an excellent opportunity to clarify his ideas. In view of this letter the question arises why Descartes reacts so hostily in letters of a later date.

Discovery

Dr. Erik-Jan Bos, research-fellow of the Zeno-Institute, the research institute of the Department of philosophy of Utrecht University (the Netherlands), found a brief and undetailed mention of the letter in a description of the manuscript collection of the library of Haverford College (Haverford, PA, USA). Thanks to the generous co-operation of Mr. John Anderies, Head of Special Collections at Haverford College, it became clear that it was an authentic unknown letter of Descartes. Bos had discovered another autograph letter of Descartes in 2003.

Theft

Originally the letter was part of the collection of the Institut de France, from which it was stolen, together with many other letters of Descartes by Guglielmo Libri, professor of mathematics at the Collège de France. Libri sold the letters but was sentenced, in absentia, in 1850. Despite the fact that later the French government managed to retrieve a part of these letters, it is certain that some letters are still missing. The letter of 27 May 1641 was finally acquired by the autograph collector Charles Roberts, whose widow donated his rich collection to Haverford College in 1902. Upon discovery and confirmation of the letter’s storied past, Haverford President Stephen Emerson contacted Gabriel de Broglie, Chancellor of the Institut de France, to offer its return. In appreciation for the care given to the letter for over a century, the College will be awarded an Institut de France prize in June 2010.

Publication

Later this year the letter will be published in Archiv für Geschichte der Philosophie. Dr. Erik-Jan Bos works on a new critical edition of Descartes’ correspondence, which will be published by Oxford University Press. His project is part of a larger project ‘Descartes and his network,’ led by Prof. Theo Verbeek, which is sponsored by NWO (the Netherlands Organisation for Scientific Research).

Image

The accompanying scan of the letter shows Descartes’ signature.

Further information

For further information, see the website of Erik-Jan Bos.

Roy Keeris, press communications officer Utrecht University, + 31 (0)30 253 2411, r.b.keeris@uu.nl.