Descartes' Dream

DESCARTES’ DREAM A USED BOOK STORE I love to browse through used bookstores. Not surprisingly, some of the best ones happen to be in university towns. That is one of the perks of going to meetings of scientific societies because they are almost always held on large university campuses. About 10 years ago, a collection of ecological and organismal societies met on the campus of the University of Toronto. Certainly, Toronto is much more than a university town, but the city is made of many neighborhoods, each with its distinctive character. That is true, too, of the area around the university. Between talks and meetings I wandered the university neighborhood and went into a large used bookstore. The store was average in size, but its holdings were amazing. I recall that I missed a whole session of talks because I spent so much time browsing and talking to the store owner. Although there were several glass cases with books that appeared to be important, there was one case with some interesting and very old books. One book was covered with white velum and occupied a place of some importance. I asked if I could see the book, but the proprietor, with whom I had been talking about various old science books, just smiled and handed me a pair of white cotton gloves. He unlocked the case and urged me to open it up and read the title. I caught my breath as I read Discours de la Methode (Discourse on the Method) . The book was from the mid seventeenth century and was written by Rene Descartes. AN ETERNAL STUDENT There is need of a method for finding out the truth. –Rene Descartes Rene Descartes was born on March 31, 1596 to an aristocratic family in France. His father was a counselor of the Parliament of Brittany. On his mother’s side he appeared to have been descended from a long line of physicians. His parents sent him to the Jesuit school of La Fleche in 1606. until he left in 1614. He was supposed to have been sickly as a child and even the Jesuits allowed him to sleep until noon while there, a habit that he retained through his life. After La Flesche, Descartes spent the next two years in Paris studying mathematics. He then left Paris in 1617 to study law in Poitiers. Some authorities say that he received a law degree from Poitiers; however, that appears unlikely because he left within a year and never claimed to have a degree in law. Furthermore, because he was an aristocrat, and had enough money to support himself, he did not have to worry about how to make a living. Consequently, he had no need of a degree or a profession. Descartes became a volunteer without pay in the Dutch army of the Prince of Orange in whose service he wandered over much of Europe. He finally settled in the Netherlands in 1628. While there, he attended universities at Franeker (1629) and Leyden (1630). Again, he seemed to have been attracted to universities for the sake of learning, not to obtain a degree. Descartes was not an extravagant man, but he lived comfortably by a pension that he received from his father. Later, he inherited money from his mother’s and father’s estates, which allowed him the freedom to live as he chose. How is it, then, that a man who was without ambition became a household name in Europe? In 1628, Descartes met with Cardinal Berulle who implored the young aristocrat to 1 use his talents. In fact he stressed that God would hold Descartes accountable for how he employed his abilities. Berulle’s admonition seemed to light a fire in Descartes, who showed a burst of productive work that lasted from 1629 to 1649. During that time he lived in Holland, but although he remained in the same country, he did not like to live in the same place and moved about twenty times during that twenty-year period. Always he required that he live in the neighborhood of a university and a Catholic Church, both of which were sources of inspiration. Much earlier, Descartes claimed to have had a series of dreams in which the method for discovering fundamental laws governing nature were revealed by “the Spirit of Truth”. He “experimented with this method and the application of mathematics to questions in physics. LAWS AND EXPLANATION ...To divide up each of the difficulties which I examined into as many parts as possible, as seemed requisite in order that it might be resolved in the best manner possible. –Rene Descartes Descartes’ method included several steps. The first of which was to reject everything so that the observer would be objective and without prejudice. The second step was to divide up the problem into as many parts as possible. In this way, the problem could be reduced to simpler and simpler components. This reduction or simplification of the problem is really an attempt to explain the problem. Descartes and his contemporaries were concerned with large problems like why do the planets stay where they do. That is, why do they seem to move around the sun (he agreed with Galileo on this) and not fall to the sun or fly away out of orbit. Later, Isaac Newton formulated a mathematical statement, which he called the law of gravity that described the movement of the planets. In this law, Newton said that it made no difference whether the object was a planet or an apple, two bodies attract each other according to the product of their masses and the inverse square of their distance from each other. This law describes the behavior of orbiting planets, falling apples, and any objects of mass. Nevertheless, Newton’s law of gravity does not define gravity itself. The other laws of chemistry and physics behave the same way. For example, Boyle’s Law describes the relationships between the pressure, temperature, and volume of a gas. It does not explain what pressure and temperature are, but describes their relationships with mathematical precision. Chemistry and physics are generally referred to as the physical sciences. Laws within these sciences are universal and ultimately, all phenomena in nature must reduce to one or more of the physical laws. Some claim that this is the way in which phenomena are explained, by reducing them to natural laws. In essence, this is the second step of Descartes’ method. That is, the phenomenon should be reduced to descriptive laws and, thereby, be explained. AN INVERTED PYRAMID ...To separate out what is quite simple from what is complex. –Rene Descartes The science of Descartes was mainly that of optics and mechanics. His book Discourse was written around the birth of Newton (and the death of Galileo), and Descartes, 2 himself, died before the publication of Newton’s Principia. Nevertheless, he recognized that the physical sciences were necessarily the simpler or less complex of the sciences. Other sciences like Biology and Geology are more complex than Chemistry and Physics. The more complex sciences are more defined by complex interactions of their constituent parts. For the sake of explanation, the landforms around my home in Freeburg, PA can be reduced to the actions of erosion, sedimentation, plate tectonics, geochemistry, climate, and hydrology. Those can be reduced to aspects of chemistry and physics. Although they are reducible to the laws of chemistry and physics, those laws do not indicate the particular interrelationships that gave rise to Pleasant Valley. That would have to be given in a narrative style more like that of a historian than a physicist although the story must not violate physical law. Thus, I view the sciences as an inverted pyramid (see Figure 1) with the less complex and more abstract disciplines at the bottom. Above chemistry and physics rise geology and biology. These are crowned by the most complex of the sciences, namely Environmental Science and Psychology. FIGURE 1. The hierarchy of explanation in the sciences. Sciences at the top are the more complex. Ultimately, all sciences reduce to the laws of the physical sciences (divided from the complex sciences by the horizontal bar). Physics is described by mathematics. 3 Because the complex sciences depend upon interrelationships that might be unique, they cannot generate their own universal laws. For example, there can be no universal laws of life because life as we know it is unique to planet earth. I have no doubt that if life is found elsewhere, it would be so different in its details that we would have some difficulty even recognizing that it is life. WHAT? HOW? WHY? It is true as regards the experiments which may conduce to this end, that one man could not possibly accomplish all of them. –Rene Descartes Biology, like the sciences as a whole, displays a nested or hierarchical form. As I look out of the window in my study, I see a forested ridge. The forest community is made up of a collection of species each represented by its own collection or population. The population is made up of individuals, each of which (in the case of the plants, animals and fungi) is constructed of organs that are made of tissues composed of cells. All of these have their own anatomies and physiologies defined by their particular molecular biologies. Another way to say it is that the study of life ranges in complexity from molecular biology (the simplest) to ecology (the most complex). The simpler the science, the more easily it lends itself to the experimental method. Experimentation requires, above all, that the system in question be simple or simplified.

Load more