Published Article/Book Citation
The definitive version was published in Rue Descartes, 60, 2, 2008, pp. 105-113. http://www.cairn.info/revue-rue-descartes-2008-2.htm
Author posting. Copyright © Presses Universitaires de France, 2008. This is the publisher's version of the work. It is posted here by permission of Presses Universitaires de France for personal use, not for redistribution.