Karen Detlefsen

In 2020, the University of Pennsylvania instituted a graduate certificate in public philosophy. In many ways, this certificate formalized and recognized the public engagement work that graduate students in the philosophy department and beyond had been involved with for some years. One element of the certificate, however, was pivotal in moving our work in public philosophy forward in important ways. This element is the research seminar in public philosophy. In this paper, we recount the motivation for the creation of the certificate and especially the motivation for the inclusion of the research seminar. We also explore ways in which such a certificate, along with the deliberately self-reflective work of the research seminar, might help us reimagine the nature and value of philosophy and its connection with human life and flourishing. We focus on metaphilosophical themes such as the very nature of philosophy and the philosopher as well as the importance of cultivating a new generation of academic philosophers committed to transcending the distinction between the academy and the public and, relatedly, between academic philosophy and public philosophy.

This dissertation is an examination of the emergence of the preformation doctrine of generation in three early modern philosophers: Descartes, Malebranche and Leibniz. Received wisdom on this question maintains that the preformation doctrine became so popular in the seventeenth century because it seemed most capable of explaining generation of living beings within the limits of the reigning mechanical philosophy. This dissertation considers another motivation, generally neglected by commentators, for the rise of this doctrine in the early modern period---namely to account for the individuation, unity and enduring identity of material bodies. ;With the clear exception of Leibniz, early modern rationalists rarely developed robust theories of material individuation, but I argue that the living, organic being is a paradigm example of the enduring material unity for all three philosophers under examination. Descartes' theory of generation, however, is unable to account for the unity of this living being, although it is able to account for species-specific complexity even given the nascent mechanism that he embraced. So Malebranche introduces preformation as a way to remedy this failure. ;Nonetheless, both Descartes' and Malebranche's forms of mechanism threaten the material unity of organisms on a number of fronts. Leibniz's starting point, I argue, is the problem of individuation very broadly conceived, and his solutions to the various aspects of this problem all dovetail to culminate in his quite unique theory of preformation and in a notably different version of mechanism than that held by his predecessors. ;All three thinkers draw on Aristotelian ideas about substantial unity and organic beings, though they do so in different ways. I thus show that the usual story of the early moderns' radical break from Aristotelianism crumbles under a consideration of the individuation of living individuals. I also argue that teleology enters into all three philosophers' work more than normally supposed. Finally, I use my findings to suggest new ways of looking at central metaphysical questions of the seventeenth century and new ways of reading the historiography of generation in the early modern period

In this paper, I argue that Margaret Cavendish’s account of freedom, and the role of education in freedom, is better able to account for the specifics of women’s lives than are Thomas Hobbes’ accounts of these topics. The differences between the two is grounded in their differing conceptions of the metaphysics of human nature, though the full richness of Cavendish’s approach to women, their minds and their freedom can be appreciated only if we take account of her plays, accepting them as philosophical texts alongside her more standard philosophical treatises.

This paper has two parts: In the first part, I give a general survey of the various reasons 17th and 18th century life scientists and metaphysicians endorsed the theory of pre-existence according to which God created all living beings at the creation of the universe, and no living beings are ever naturally generated anew. These reasons generally fall into three categories. The first category is theological. For example, many had the desire to account for how all humans are stained by original sin (we were all there). As another example of a theological motivation, some take the organism as an obvious starting point for a teleological argument for God’s existence, and this staring point is sometimes developed into a full-blown theory of pre-existence. The second category could be thought of as non-theological metaphysical, and paramount here is the desire to deal with the metaphysical problem of individuation. So, for example, Leibniz embraces a version of hylomorphism in order to overcome difficulties with Descartes’ theory of material substance, including the difficulty of how to account for enduring material individuals, and Leibniz’s hylomorphism is closely linked with his embrace of pre-existence. The third category might be termed “biological”, and one example of such a concern is how to explain the organic unity of living beings where the whole seems to ontologically precede the parts. This is frequently translated into a temporal priority of whole to parts, and thus pre-existence is posited. Of course, many natural philosophers of the early modern period embrace pre-existence for more than one reason, but in general, these are the three classes of motivations one might have for embracing the theory. In the second part of the paper I examine in detail one argument that appears in the work of Malebranche. On the face of it, this argument seems to be a biological one, specifically the biological or organic holism argument mentioned above. But upon closer examination, I shall argue, Malebranche’s reasons for endorsing pre-existence bring together several of the arguments discussed in the first part of the paper. I conclude with some considerations about what we can learn about Malebranche as a natural philosopher from his motivations for holding the pre-existence doctrine of generation.

Malebranche is both an occasionalist and an advocate of the preformationist theory of generation. One might expect this given that he is a mechanist: passive matter cannot be the source of its own motion and so requires God to move it (occasionalism); and such matter, moving according to a few simple laws of motion, could never fashion something as complex as a living being, and so organisms must be fashioned by God at Creation (preformationism). This expectation finds a challenge in Kant's depiction of the relation between causation and generation. According to Kant, preformation is the generation theory one would expect the advocate of the pre-established harmony to endorse, while the occasionalist would endorse a theory whereby God directly forms the organism upon every insemination. I make sense of Malebranche's position in light of Kant's suggestion by examining the relation Malebranche sees between science and metaphysics, the roles that he believes empirical investigations and final causes have in scientific practice and explanation, and the role of the supernatural in Malebranche's philosophy.

It has often been noted that Margaret Cavendish discusses God in her writings on natural philosophy far more than one might think she ought to given her explicit claim that a study of God belongs to theology which is to be kept strictly separate from studies in natural philosophy. In this article, I examine one way in which God enters substantially into her natural philosophy, namely the role he plays in her particular version of teleology. I conclude that, while Cavendish has some resources with which to partially alleviate this tension, she is nonetheless left with a significant difficulty.

Between 1653 and 1655 Margaret Cavendish makes a radical transition in her theory of matter, rejecting her earlier atomism in favour of an infinitely-extended and infinitely-divisible material plenum, with matter being ubiquitously self-moving, sensing, and rational. It is unclear, however, if Cavendish can actually dispense of atomism. One of her arguments against atomism, for example, depends upon the created world being harmonious and orderly, a premise Cavendish herself repeatedly undermines by noting nature’s many disorders. I argue that her supposed difficulties with atomism expose a deeper tension in her work between two fundamental metaphysical commitments each of which has substantial philosophical support: her monist theory of the material world (which maintains that there exists just one natural substance which is the single principal cause) and her occasional theory of causation (which requires multiple finite principal causes in nature -- causes that might be considered individual substances). Her monism undermines atomism while her theory of occasional cause seems to rest on a conception of nature that would be especially friendly to atomism. I argue further that we can solve this tension within a Cavendishian framework in such a way as to preserve her theory of causation and her monism, but that this solution depends upon our taking her monism in a particular (and weak) form. I finally note that we can best make sense of her unique and interesting form of monism by acknowledging her social-political motivations in addition to her motivations in natural philosophy.

As a practicing life scientist, Descartes must have a theory of what it means to be a living being. In this paper, I provide an account of what his theoretical conception of living bodies must be. I then show that this conception might well run afoul of his rejection of final causal explanations in natural philosophy. Nonetheless, I show how Descartes might have made use of such explanations as merely hypothetical, even though he explicitly blocks this move. I conclude by suggesting that there is no reason for him to have blocked the use of hypothetical final causes in this way.

In this paper, I consider Descartes’ Sixth Meditation dropsy passage on the difference between the human body considered in itself and the human composite of mind and body. I do so as a way of illuminating some features of Descartes’ broader thinking about teleology, including the role of teleological explanations in physiology. I use the writings on teleology of some ancient authors for the conceptual (but not historical) help they can provide in helping us to think about the Sixth Meditation passage. From this, I draw several points, most notably that the Sixth Meditation passage is primarily concerned with the natures of body and composites, and that the issue of teleological explanation is derivative of this primary interest. So, we – and Descartes – must come to terms with what he takes the nature of the composite to be such that it has an intrinsic end-referred nature which grounds teleological explanations. I consider three possibilities: the human composite is a third type of substance – a hylomorphic substance; there is a sort of “satisfaction” relationship between mind and body (each of which retains its own distinct nature in the composite) such that the mind confers teleological value on the body; and there is a sort of “satisfaction” relationship between mind and body (each of which retains its own distinct nature in the composite) such that the mind recognizes teleological value in the body. None of these interpretations is without problems. So in the concluding section, I sketch a program for future research, specifically, trying to render Descartes’ teleological thinking consistent by distinguishing between the metaphysical natures of things (the concern of his Sixth Meditation passage) and the physical natures of things (his concern in his physiological writings).