Kant was well versed in many of the debates taking place in the life sciences during his day. One of the more central areas of contention concerned the proper means for discriminating between material bodies composed of organised parts (like clocks or automatons) and living material bodies composed of organised parts (like plants and animals). For many theorists, it seemed clear that the physically organised structure of a body was distinct from any vital forces responsible for the life processes or (...) metabolism at work within it. This was the approach taken by the chemist Georg Stahl (1659-1734), for example, who resisted attempts to provide a mechanical account of metabolism, arguing instead that only something like a physis or anima could explain a living body’s capacity for the movement of otherwise inert material parts. This was a position which Kant appears to have appreciated when, in discussing the issue in 1766, he exclaimed “I am convinced that Stahl, who is disposed to explain animal processes in organic terms, was frequently closer to the truth than [the mechanists] Hofmann or Boerhaave, to name but a few” (2:331). And indeed, by 1790 Kant would reach conclusions similar to Stahl’s regarding the manner by which we must reflectively judge animal processes to be operating, given that for Stahl the biological body was best taken to be a complex, self-organising system of material parts and a purposive force or physis responsible for their ongoing interrelation. (shrink)

I. Introduction Siris, Berkeley's last major work, is undeniably a rather odd book. It could hardly be otherwise, given Berkeley's aims in writing it, which are three-fold: 'to communicate to the public the salutary virtues of tar-water,'1 to provide scientific background supporting the efficacy of tar-water as a medicine, and to lead the mind of the reader, via gradual steps, toward contemplation of God.2 The latter two aims shape Berkeley's extensive use of contemporary natural science in Siris. In particular, Berkeley's (...) focus on what he calls fire (or aether or light) as a quasiuniversal 'cause' of natural change3 serves these purposes, for the 'activity' of the aether, in his view, can both explain the miraculous virtues of a certain medicine, i.e. tar-water, and reveal God's action and his divine order.4 Berkeley's corpuscular speculations, including his use of fire-theory, are not especially idiosyncratic as natural philosophy. In his theorizing, as Jessop and other have noted, he is heavily indebted to the work of Hermann Boerhaave, the Dutch chemist, botanist, and physician whose teachings were highly influential in mid-eighteenth century Britain.5 Boerhaave, along with other Dutch natural philosophers cited by Berkeley, assigned a central role in accounting for physio-chemical activity to fire, a subtle, insensible particulate substance, sometimes identified with light. (shrink)

Although George Berkeley himself made no major scientific discoveries, nor formulated any novel theories, he was nonetheless actively concerned with the rapidly evolving science of the early eighteenth century. Berkeley's works display his keen interest in natural philosophy and mathematics from his earliest writings (Arithmetica, 1707) to his latest (Siris, 1744). Moreover, much of his philosophy is fundamentally shaped by his engagement with the science of his time. In Berkeley's best-known philosophical works, the Principles and Dialogues, he sets up his (...) idealistic system in opposition to the materialist mechanism he finds in Descartes and Locke. In De Motu, Berkeley refines and extends his philosophy of science in the context of a critique of the dynamic accounts of motion offered by Newton and Leibniz. And in Siris, Berkeley's flirtation with neo-Platonism draws inspiration from the fire theory of Boerhaave as well as Newton's aetherial speculations in the Queries of the Optics. In examining Berkeley's critical engagement with the natural philosophy of his time, we will thus improve our understanding of not just his philosophy of science, but of his philosophical corpus as a whole. (shrink)