Descartes: Philosophical Pioneer

. DESCARTES: AN INTELLECTUAL BIOGRAPHY

By Stephen Gaukroger

Clarendon Press

499 pp., $35

One day Rene Descartes (1596-1650) was eating lunch in a Paris bistro when the waiter asked, "Will there be anything else, m'sieu?" the story goes that Descartes replied, "I think not," and vanished!

Most students learn of Descartes only in that he said cogito ergo sum - "I think, therefore I am." This magisterial biography by Stephen Gaukroger, president of the Australian Society for the History of Philosophy, exhaustively explores the question of what it was Descartes was thinking about.

Gaukroger has immersed himself in Descartes' world. He has read the published and posthumous works, the letters, and anything else that might conceivably have a bearing on Descartes' life and work, including such obscure finds as the Ten Modes of Aenisdemus of Knossos and the writings of Hermes Trismegistus. His interest in Descartes began some 25 years ago. "It was with unbounded enthusiasm that I devoured the 'Discourse on Method,' sitting in the shade of a tree in the Borghese Gardens in Rome in the summer of 1970, just before I started studying philosophy at university."

The image of a garden flooded with sunlight might well describe this comprehensive intellectual biography, for it opens to the light of inquiry the dark and somewhat forbidding world of intellectual life in 17th-century Europe.

Descartes has been called the father of modern philosophy. In his publications, and in his extensive correspondence with the Minimite friar Marin Mersenne, he explored almost every issue of intellectual concern in his day. Father Mersenne was at the center of the "Republic of Letters," in communication with Descartes and Fermat in France, Galileo in Italy, and others.

At that time, the modern distinctions between science, philosophy, and theology hardly existed. The Latin-speaking, Jesuit-educated, European literati of the day formed an international community, bound by shared interests. Descartes' goal, at one point in his life, was the construction of a mathesis universalis, a universal natural philosophy that encompassed all these disciplines in a common framework.

In this great task, he does not seem to have been much impeded by modesty. He writes to Mersenne in 1632, for example, that he is "dissecting the heads of different animals in order to explain what imagination, memory etc., consist of." He also insisted that the English physician and physiologist William Harvey must be wrong in his theory that the heart was a pump, since there was no obvious source of power. Descartes insisted the heart must be like a furnace, in which the blood is warmed.

This account of physiology was a part of Descartes' larger belief that all natural forces could be explained in terms of working mechanical principles. "The universe, as Descartes represents it, consists of an indefinite number of contiguous vortices, each with a sun or a star in the center, and planets revolving around the center." This theory was widely accepted in Europe even after Newton presented his more plausible formulation of planetary motion in terms of the law of gravity.

Descartes was working on these speculations when word came in 1633 of the condemnation and burning of all copies of Galileo's sun-centered cosmology. At this point in Descartes' career he ceased what we would call scientific work in favor of philosophical inquiry.

His most famous work, the "Discours de la Methode" ("Discourse on the Method of Conducting Reason and Seeking Truth in the Sciences") of 1637, presented the idea of moral skepticism - what Gaukroger describes as hyperbolic doubt. "There is nothing that cannot be doubted, except that one is doubting, and this requires that there be something ... that is doing the doubting." Thus, "I think, therefore I am;" if I can doubt, I must exist. On this basis, Descartes set out to re-create a moral system.

From a late 20th-century perspective, Descartes' only lasting achievement was probably in mathematics. In no small measure, it was his invention of analytic geometry that made possible Newton's and Lebnitz's development of calculus, which in turn caused the overthrow of Cartesian science.

Ironically, his mathematical work was far less revolutionary than his theories in science and philosophy.

Mathematics, it has been argued, is the one scientific discipline in which there is the possibility of genuine progress. Not many modern chemists or physicists would argue that there are only four elements, or that heat is caused by an excess of phlogiston (an imaginary principle of fire). The history of mathematics, on the other hand, includes many ideas still taught today, such as Euclidean geometry or the algebra of the Arab scholar al-Kwarizmi (from whose name we get the term "algorithm").

Finally then, we come away from the study of Descartes' life with a deeper insight into the problem of progress in the sciences. Descartes was just plain wrong about a lot of things, including his theories of physiology and planetary motion. Gaukroger's work explicitly focuses on "the relations of Descartes' intellectual pursuits and the intellectual and cultural environment in which they were pursued."

If we can understand something of how Descartes' ideas were shaped by the intellectual culture of his century, and how they have in turn contributed to our own, then we have learned something about ourselves.

By studying the ways that Descartes and his contemporaries viewed their world, perhaps we can better understand how our own perceptions may be affected by our preconceptions.

It is tempting, with the advantage of hindsight, to dismiss Descartes' efforts to understand his relation to the universe as failed attempts. (But that would be putting Descartes before de hors.) Much in his thinking is rich and complex, and we would do well to give our respect and admiration to his life's struggle to make intelligible the building materials of creation.