In the past decade, several Descartes scholars have gone on record claiming that, for biological purposes, Descartes likely accepts the practical scientific necessity of the existence of “physical natures,” even while his official substance-mode ontology and his characterization of matter in terms of extension do not license the existence of physical natures. In this article, I elaborate on the historical context of Descartes’s biology, the “practical scientific necessity” just mentioned, and argue, contrary to other interpretations, that Descartes does offer a (...) philosophical justification for the existence of physical natures, albeit not by appeal to the categories of substance and mode, or matter as such, but by appeal to our “nature” as a union between mind and body. (shrink)

I argue that Descartes explains physiology in terms of whole systems, and not in terms of the size, shape and motion of tiny corpuscles (corpuscular mechanics). It is a standard, entrenched view that Descartes’ proper means of explanation in the natural world is through strict reduction to corpuscular mechanics. This view is bolstered by a handful of corpuscular–mechanical explanations in Descartes’ physics, which have been taken to be representative of his treatment of all natural phenomena. However, Descartes’ explanations of the (...) ‘principal parts’ of physiology do not follow the corpuscular–mechanical pattern. Des Chene has identified systems in Descartes’ account of physiology, but takes them ultimately to reduce down to the corpuscle level. I argue that they do not. Rather, Descartes maintains entire systems, with components selected from multiple levels of organization, in order to construct more complete explanations than corpuscular mechanics alone would allow. (shrink)

Descartes's conception of matter changed the account of physical nature in terms of extension and related quantitative terms. Plants and animals were turned into species of machines, whose natural functions can be explained mechanistically. This article reflects on the consequences of this transformation for the psychology of human soul. In so far the soul is rational it lacks extension, yet it is also united with the body and affected by it, and so it is able to act on extended matter. (...) The article examines Descartes's concept of scientia and his different uses of nature, and argues that there is much more continuity between Aristotelian and Cartesian psychology than is usually recognized when it comes to an explanation of the functions of the embodied human soul. If this makes psychology unfit for inclusion in the new science of nature, its object is still a natural phenomenon and has an important place within scientia as Descartes conceived of it. (shrink)

Receptions of Descartes is a collection of work by an international group of authors that focuses on the various ways in which Descartes was interpreted, defended and criticized in early modern Europe. The book is divided into five sections, the first four of which focus on Descartes' reception in specific French, Dutch, Italian and English contexts and the last of which concerns the reception of Descartes among female philosophers.

In 1675, Burchard de Volder (1643–1709) was the first professor to introduce the demonstration of experiment into a university physics course and built the Leiden Physics Theatre to accommodate this new pedagogy. When he requested the funds from the university to build the facility, he claimed that the performance of experiments would demonstrate the “truth and certainty” of the postulates of theoretical physics. Such a claim is interesting given de Volder’s lifelong commitment to Cartesian scientia. This chapter will examine de (...) Volder’s views on experiment and show that they are not Newtonian or inductivist, as is sometimes claimed. While de Volder thinks we need deductive reasoning from first principles to provide evidence of the certainty of the content of our physical theories, he also contends that we need experiment to provide evidence of the certainty of the existence of the particular bodies those theories discuss. This approach to experiment is based on a distinction between rational certainty and the certainty of material bodies in the actual world. While this account is deeply influenced by Descartes, it is importantly different than Descartes’ distinction between absolute and moral certainty. De Volder’s “Cartesian Empiricism” is best understood as a continuation and further development of a long tradition of teaching through observation at Leiden. (shrink)

This chapter examines the mechanistic psychology of Descartes in the _Passions_, while also drawing on the _Treatise on Man_. It develops the idea of a Cartesian “psychology” that relies on purely bodily mechanisms by showing that he explained some behaviorally appropriate responses through bodily mechanisms alone and that he envisioned the tailoring of such responses to environmental circumstances through a purely corporeal “memory.” An animal’s adjustment of behavior as caused by recurring patterns of sensory stimulation falls under the notion of (...) “learning,” behavioristically conceived. Indeed, Descartes’s animal-machine hypothesis may well be a distant ancestor to Watsonian behaviorism, via T. H. Huxley (1884). The final two sections of the chapter take stock of what psychological capacities Descartes ascribed to mind, body, or both, and consider those capacities that we might now plausibly construe as being explicable by nonmentalistic mechanisms as opposed to those that at present remain unreducedly mentalistic. -/- This chapter derives from a lecture delivered at the University of King's College (Halifax, Nova Scotia) as part of a year-long series on Descartes and the Modern. The lecture series was co-sponsored by the programs in History of Science and Early Modern and Contemporary Studies. (shrink)

This chapter considers philosophical problems concerning non-human (and sometimes human) animals, including their metaphysical, physical, and moral status, their origin, what makes them alive, their functional organization, and the basis of their sensitive and cognitive capacities. I proceed by assuming what most of Descartes’s followers and interpreters have held: that Descartes proposed that animals lack sentience, feeling, and genuinely cognitive representations of things. (Some scholars interpret Descartes differently, denying that he excluded sentience, feeling, and representation from animals, and I consider (...) the evidence for these interpretations as well.) Given that Descartes denied any sort of soul to animals, his other philosophical commitments entailed that he must explain the vital and sensitive powers of non-human animals through purely material causes. Indeed, he welcomed this task, for he was engaged in the larger project of providing purely mechanistic explanations for all natural phenomena of the material world. Animal bodies form functional unities that are adapted to environmental circumstances. In his new physics, Descartes sought to discover or hypothesize material mechanisms that would explain the physiological and behavioral capacities of animals, including how they maintain themselves by seeking food and drink, reproduce themselves, and modify their behavior to fit current circumstances. Metaphysically, his new perspective raised the problem of accounting for the functional unity of the animal body considered as a purely material construction, devoid of an active, organizing power such as the sensitive soul. Descartes’s project becomes even more challenging if we ask whence come such mechanisms that are capable of performing the functions of living things. Officially, Descartes endorsed the accepted theological orthodoxy, that God designed and created the bodily mechanisms of humans and animals. However, in his natural philosophy he set himself the task of explaining the origin of animals as part of the natural development of the universe out of an original chaotic soup of material particles. Within this naturalistic perspective, he must explain how, through purely material processes, the functionally organized bodies of living things (plants and animals) could be produced from non-living matter. Without a designing creator, how do animal bodies arise that are capable of digesting food, growing, reproducing, and performing the behaviors needed to preserve life and health? (shrink)

This article calls into question the notion that seventeenth-century authors such as Descartes and Leibniz straightforwardly conceived the mind as something "outside" nature. Descartes indeed did regard matter as distinct from mind, but the question then remains as to whether he equated the natural world, and the world of laws of nature, with the material world. Similarly, Leibniz distinguished a kingdom of final causes (pertaining to souls) and a kingdom of efficient causes (pertaining to bodies and motions), but the question (...) remains as to whether he equated nature with the second kingdom alone, or included both kingdoms within nature. Although Kant sundered Leibniz's envisioned connection between the two kingdoms, even he did not place mind fully outside nature. (shrink)