Leibniz famously argues that there must be simple substances, since there are composites, and a composite is nothing but a collection of simples. I reconstruct Leibniz’s argument, showing that it relies on a commitment to mereological nihilism (i.e., the view that composites cannot be true beings). I show further that Leibniz endorses mereological nihilism as early as the 1680s and offers both direct and indirect support for this commitment: indirect support via the notion of unity and direct support via the (...) notion of persistence. I then assess the alignment of Leibniz’s mereological nihilism with his other commitments during the 1680s, including his potential commitment to corporeal substances. I argue that any viable interpretation of Leibniz’s commitment to corporeal substances is compatible with mereological nihilism, which provides a new perspective both on Leibniz’s developing theory of substance and on his mature theory of simple substance. (shrink)

In this paper, I argue that Kant adopted, throughout his career, a position that is much more akin to classical accounts of epigenesis, although he does reject the more radical forms of epigenesis proposed in his own time, and does make use of preformationist sounding terms. I argue that this is because Kant thinks of what is pre-formed as a species, not an individual or a part of an individual; has no qualm with the idea of a specific, teleological principle (...) or force underlying generation, and conceives of germs and predispositions as specific constraints on such a principle or force. Neither of these conceptions of what is “preformed”, I argue, is in strict opposition to classical epigenesis. I further suggest that Kant’s lingering use of preformationist terminology is due to his belief that this is required to account for the specificity of the specific generative force; his resistance towards the unrestricted plasticity of the generative force in radical epigenesis, which violates species-fixism; and his insistence on the internal, organic basis of developmental plasticity and variation within species. I conclude by suggesting that this terminological and interpretative peculiarity is partly due to a larger shift in the natural philosophical concerns surrounding the debate on epigenesis and preformation. Specifically, it is a sign that the original reasons for resisting epigenesis, namely its use of specific, teleological principles and its commitment to the natural production of biological structure, became less of a concern, whereas unrestricted plasticity and its undermining of fixism became a real issue, thereby also becoming the focal point of the debate. (shrink)

This article closely compares the opposing foundations of theoretical philosophy in René Descartes and Ayn Rand. The developmental course of Rand's foundations, with their continual opposition to Descartes, is tracked. Arguments particularly against Descartes are assembled in this article, and the bountiful contemporary scholarship on Descartes is engaged.

RESUMEN Durante el siglo XVII, el reloj parece el modelo más adecuado para pensar los seres vivos. El filósofo alemán G. W. Leibniz es parte de la tradición mecanicista que concibe los seres vivos a partir del modelo del reloj o de los autómatas, pero establece una distinción esencial entre máquinas naturales y artificiales, que muestra los límites de este modelo. Las primeras son máquinas infinitamente complejas, máquinas dentro de máquinas ad infinitum, las segundas no, alcanzan un límite de complejidad. (...) Esta distinción obliga a ir más allá del reloj como modelo de los seres vivos, pues este modelo resulta insuficiente para comprender la dinámica propia de los seres vivos, en al menos dos aspectos: a) deja sin explicar el origen de la estructura o forma del ser vivo; b) no establece un principio interno de actividad que fundamente la unidad dinámica y estructural del ser vivo. Con su noción de organismo o máquina natural, Leibniz intenta resolver estas insuficiencias del modelo puramente mecánico: a) en su propuesta el ser vivo no se constituye de manera mecánica o serial, sino de una vez, por un acto de creación; b) la conservación del ser vivo en el tiempo sólo es comprensible a partir de un principio de actividad intrínseca que dota de unidad, actividad y estructura al viviente. ABSTRACT During the seventeenth century, the clock seems the most appropriate model for thinking about living beings. The German philosopher G. W. Leibniz, is part of the mechanical tradition that conceives living beings from the clock or the automata’s model, but he establishes an essential distinction between natural and artificial machines. This distinction shows the limits of the mechanical model. The machines of nature are infinitely complex machines, machines within machines ad infinitum; the artificial machines, instead, reach a limit of complexity. This distinction forces us to go beyond the clock as a model of living beings, because this model is insufficient to understand the dynamics of living beings, in at least two aspects: a) it is not able to explain the origin of the living being’s structure or form; b) it does not establish an internal principle of activity grounding the living being’s dynamic and structural unit. With his notion of organism or natural machine, Leibniz tries to solve these insufficiencies of the purely mechanical model: a) in his proposal, the living being is not constituted mechanically or serially, but at once, by an act of creation; b) the conservation of the living being in time is only understandable from a principle of intrinsic activity that provides unity, activity and structure to living beings. (shrink)

This dissertation addresses the heartbeat and the systems of natural philosophy that were used to explain it in the 17th century. Thus, I work in two domains of explanation. The first domain is physiology, in which William Harvey correctly ordered the heart’s systolic and diastolic motions, while René Descartes incorrectly reversed them. By looking at Harvey and Descartes’ more complete physiological models I reconsider the controversy that spun out of their divergent accounts. The second domain is the junction of physics (...) and metaphysics, representing the frameworks of natural philosophy behind physiology. I argue that Harvey’s physiology was correct while his supporting principles were “wrong,” and Descartes’ physiology was incorrect while his supporting principles were “right.” Thus, my thesis is that Harvey was “right” but perhaps for the wrong reasons, while Descartes was “wrong” but perhaps for the right reasons. Of course, this judgement is made from a contemporary perspective. By using a contextualist approach to history, I aim to show how the controversy between Harvey and Descartes resolved in Nicolas Steno, when he discovered that the heart is a muscle. (shrink)