L’Arbre et le labyrinthe: Descartes selon l’ordre des Lumières (review)

In this adapted extension of her 1990 Bologna volume, Mariafranca Spallanzani presents a dauntingly rich assessment of her chosen theme, introduced by a summary of previous contributions concerning Descartes’s influence on the Lumières. Part I then treats Cartesian philosophy as construed specifically in the Encyclopédie’s ‘Discours préliminaire’ and its article ‘Cartésianisme’, where, despite severe criticisms, he emerges as their avowed precursor, respected particularly for refuting scholasticism in a laudable spirit of intellectual freedom. In approaching him, the Encyclopédistes’s attitude thus differs widely from that of his own acolytes. Part II devotes its single chapter to Cartesian science, whose mathematical advances were highly lauded by a d’Alembert who simultaneously rejected his unsound and abstract cosmology. Part III treats metaphysics, revealing how Descartes’s eighteenth-century critics appreciated the anomaly whereby official French teaching accepted his rationalist theories only after Lockean empiricism had refuted them. In contrast, d’Alembert places the problem of animal souls beyond a human understanding that he consigned to fragmentary knowledge achieved via experience, albeit systematically evaluated, the latter consideration being again recognizably Cartesian. Chapter 6 extends the point, showing how the principle of methodical doubt had helped undermine religion, while the mind–body dichotomy had fed idealism in its extreme form, trends to which certain Encyclopédistes remained opposed. Spallanzani’s Part IV considers Descartes’s notion of philosophical order, whereby metaphysics forms the root of sound knowledge and physics its trunk, from which grow the three essential branches of medicine, mechanics, and ethics. Once again, Enlightenment thinkers were far from unremittingly hostile to a metaphor whose implications of order they accepted, while rejecting any overstructured rigidity: they exchange his enforced unity for an open system that remains, however, logically construed and morally defensible. Hence the immobile tree is replaced as metaphor by the exploratory mappemonde, and the light of Cartesian reason by an investigative chiaroscuro whose endeavours and implications remain positive and optimistic, symbolizing a metaphysics that is ‘sage et modeste’ rather than temerariously dogmatic. Conscious of the vicissitudes accompanying the Encyclopédie’s publication, during which disillusion infected editorial enthusiasm, Spallanzani’s overview remains laudably positive and instructive, her final section (‘Scolies’) proving particularly ingenious in its analogy between Cartesian logic and Vermeer’s tapestry of the lacemaker, alongside her readings of various Encyclopédie engravings that represent and celebrate the mechanical arts, but in a mood foreign to what was perceived as Descartes’s abstractionist intellectual sterility. At times the text may seem overburdened with notes (pp. 91–94 contain but three and a half lines of text), and at others the argument becomes repetitious: between pages 343 and 347 we learn three times that, etymologically, ‘encyclopédie’ means ‘enchaînement des sciences’, only to read the same on page 445. Otherwise, incidental misspellings, misquotations, and grammatical irregularities do intrude (sometimes up to three per page): perhaps ‘les dépôts mal firmes de la mémoire’ (sic, p. 198) hamper one who would plumb the ‘premières âges de la philosophie’ (sic, p. 423). However, and ‘marlgré tout’ (sic, p. 188), one cannot but applaud such a massively supported and soundly argued intellectual undertaking.