Introduction: Leibniz and the Sciences

In his “Eloge de Monsieur Leibnitz,” Bernard de Fontenelle wrote:

In somewhat the same way that the ancients could manage simultaneously up to eight harnessed horses, Leibniz could manage simultaneously all the sciences. Thus we need to split him up here, that is, speaking philosophically, to analyze him. Antiquity made only one person from several Hercules; we will make several savants from only one Leibniz.

(Leibniz 1768, vol. 1, p. xx)

By “science” here, Fontenelle, of course, does not mean exactly what we do now. Though in the title of this volume we speak of “Leibniz and the Sciences” in the modern sense of the term, meaning to include a variety of studies directed at understanding the natural and mathematical worlds in a systematic way, Leibniz’s own notion of a science (and Fontenelle’s as well) was quite different. For Leibniz and his contemporaries, a “science” was a body of doctrine that could be known systematically and with a high degree of certainty; it was contrasted with opinion, that which could only be understood with a lesser degree of certainty, or with an “art”, that which involved a practice rather than doctrine. ² Understood in that way, Fontenelle’s characterization of Leibniz was indeed very flattering.

Leibniz’s intellectual range was truly impressive. We can get a sense of what Leibniz meant to his contemporaries by looking at the first attempt to produce an Opera Omnia, the great 1768 edition of Dutens in six volumes, based only on readily available materials. ³ Volume I, a thick volume that runs to almost 800 pages, is devoted to theological writings; volume II (in two parts) is devoted to physics, metaphysics, and other assorted questions in natural philosophy and natural history, including medicine, geology, chemistry, and “la figure d’un chevreuil coiffé d’une manière fort extraordinaire”; volume III, almost 700 pages, is devoted entirely to mathematical writings; volume IV (in three parts) contains writings on history, law, and matters of general scholarly interest (his comments on the Renaissance Humanist Nizolius, his remarks on Chinese philosophy, etc.); volume V contains his philological and literary works and letters; and volume VI (in two parts) contains his etymological writings. The range is prodigious; it is difficult to find another thinker, either Leibniz’s contemporary or ours, who could equal the sheer variety of his interests. But it is not only for this that Leibniz was extraordinary. While not all of his intellectual programs panned out, Leibniz made significant contributions to a number of these areas, including philosophy, mathematics, physics, European history, linguistics, and geology.

It is quite tempting, as Fontenelle suggested, to divide Gottfried Wilhelm up into a multitude of littler Leibnizes. This, in fact, has been the general tendency among commentators. The philosopher’s Leibniz, the thinker who invented monads and pre-established harmony, is well known; even though, as we might infer from Dutens, Leibniz was not primarily known as a philosopher, it is as a philosopher that he is most widely studied today. Most of the other Leibnizes have been forgotten in the twentieth century, and their accomplishments have been subordinated to the author of the fantastic idealistic philosophy. Part of the goal of this issue of Perspectives on Science is precisely to show the importance of some of the other Leibnizes, at least the Leibnizes of the mathematical and the physical writings.

Tempting as it may be to divide Leibniz into smaller bits in order to conquer his thought, these essays also show at least one way in which it is misleading to read him in this way. Leibniz is quite clearly a single intellectual personality, with many different manifestations. Leibniz often quoted Hippocrates as saying that “everything conspires” (Leibniz 1989, pp. 221, 228, 296). Everything also conspires in Leibniz’s own thought, where everything is connected with everything else. In particular, Leibniz’s scientific thought is very much imbued with the same spirit as his philosophy, the love of order, of general principles, of reason; similarly, his scientific thought exerts a considerable influence on his philosophy as well. In focusing...