[Authors and titles are listed at the end of the review]
This volume builds on the foundations laid by David Charles in his seminal work The Undivided Self. Aristotle and the ‘Mind-Body-Problem’ (Oxford 2021), but extends his inquiry into a collaborative exploration of post-Aristotelian metaphysics and philosophy of mind. However, the book itself, as well as most of its essays, stand on their own as contributions to current research. In addition, Charles provides a comprehensive and illuminating introduction that incorporates key insights from his earlier work and at the same time provides a broad framework for the various analyses of ancient and medieval philosophers’ approaches to hylomorphism, that is, Aristotle’s famous distinction between form and matter. While this distinction has been fruitfully applied by Aristotle to many different issues and topics in his philosophy, following Charles’ previous work, this volume places particular emphasis on the application of hylomorphism to the so-called ‘mind-body problem’ and related philosophical issues.
The introduction highlights two key problems that Charles identifies with Aristotle’s approach. First, there is the question of how to understand the priority of form with respect to the causal efficacy of forms. Since forms must be attached to matter in order to have causal power, this casts doubt on their assumed priority. Second, there is the challenge of clarifying how to establish the unity of a natural substance if one allows matter an independent existence. This, however, seems necessary to provide a robust “bottom-up” explanation that is more in line with contemporary views of scientific discipline (p. 5).
By emphasizing the independence of matter, and thus the physicality of the principles, it also helps to understand why the editor chose to include Aristotle’s Hellenistic successors in the broader historical narrative of hylomorphism. The description of Epicurus and the Stoics as proponents of Aristotelian-style hylomorphism may at first seem surprising to some readers, and this concern is only partially allayed by the contributions themselves. However, Alexander Bown’s paper stands out in this respect. Not only does he successfully address these concerns, but he also sheds important light on a problem that has long puzzled scholars of Epicurean philosophy. Bown focuses on the ontological status of attributes and accidents that Epicurus seems to employ alongside his basic division of atoms and void. It should be noted that the successful determination of the attributes of bodies is crucial to the understanding of ordinary phenomena, for it is only in this way, for example, that certain objects can be identified.
In the following two essays, Brad Inwood and Christof Rapp attempt to situate the Stoics within the historical narrative of hylomorphism. Both authors acknowledge the challenges of this endeavor, given the well-known Stoic commitment to corporealism (pp. 68-9, 83). In their essays, they attempt to relate hylomorphism to the Stoic ontological distinction between God and matter. It is in this fundamental duality that a potential link to the Aristotelian approach seems to emerge (p. 69). Significant for the development of hylomorphism, and thus for the overall argument of the book, is the influence that Inwood suggests the Stoics may have exerted on the Peripatetics (the Aristotelian school) during the Hellenistic period, since later Aristotelians may have adopted Stoic terminology to articulate their hylomorphic accounts (pp. 79-81).
This brings us to one of the central themes and probably the highlight of the volume: the reception and further development of Aristotelian hylomorphism by the most prominent Aristotelian philosopher of antiquity, Alexander of Aphrodisias. As Reier Helle shows in his contribution, Alexander not only engaged deeply with Stoic theory, but also offered significant critiques of the Stoic account. Remarkably, Alexander’s critique of the Stoic position highlights the same two problems that Charles identified as challenges within Aristotelian theory in his introduction to hylomorphism. First, as Alexander claims, the Stoic notion of pneuma fails to explain how it imparts form in its complete mixture with matter, and second, it fails to account for the unity of the object (p. 106). But before Victor Caston and Frans A. J. de Haas explore Alexander’s own influential position, Patricia Marechal examines one of his contemporaries, the physician Galen, who was also engaged in philosophical inquiry. It is noteworthy that Galen himself claimed to follow an Aristotelian approach to explaining the soul. Upon closer examination, however, it becomes clear that his perspective is materialistic, identifying the Aristotelian formal cause with the mixture of physical elements. In this way, Galen makes the soul a kind of harmony, adopting a position that both Plato and Aristotle explicitly reject in their discussion of the soul. In a reversal of the classical Platonic and Aristotelian arguments against the view that the soul could be a mixture or harmony of the body, Galen argues that the soul as formal cause can only be causally effective if understood in this way.
Caston takes up this idea to some extent, identifying a similar approach in Alexander of Aphrodisias, whose hylomorphism he interprets as a refined form of emergentism. Like Galen, Alexander holds that “material bodies” (p. 160) are fundamental. However, through a particular mixture or harmony of these “natural materials” (p. 158), not only do specific forms emerge, but these forms also possess independent causal powers. This means that form is not merely reducible to the composition of basic material elements, but rather develops non-reductive properties that become effective at a new level. According to this view, there is a kind of hierarchy of levels, with new powers emerging at each level, each of which is dependent on the composition of the body material, even though the physical elements remain fundamental. This in turn explains and supports the robust “bottom-up” explanatory movement that Charles also emphasizes. Richard Sorabji’s paper adds to this understanding of Alexander’s position and changes the emphasis slightly by describing Alexander’s particular view in terms of “following” (p. 248). Sorabji wants to distinguish it from the weaker concept of “supervening” (p. 247). Sorabji illustrates this with the example of snow, which is also used by Alexander: its white color, as Alexander points out, is not merely based on the underlying material conditions, but “follows necessarily […] from them” (p. 248). From these more general questions, de Haas turns in his essay to Alexander’s famous account of the intellect and contrasts it with competing theories, including those from within the Aristotelian school itself, about the nature of hylomorphism (p. 175).
The contributions by Riccardo Chiaradonna, Pauliina Remes, and Miira Tuominen explore the development of hylomorphism within Neoplatonic philosophy. Plotinus’ relationship to Aristotle is particularly complex, as he is highly critical of Aristotle in his works, especially when it comes to Aristotle’s account of the soul. As Chiaradonna points out, what troubles Plotinus most about Aristotle’s understanding of the soul as a form of the body is that this interpretation brings the soul too close to the body and fails to distinguish it sufficiently (p. 198). In this view, the soul remains an attribute of the body, whereas Plotinus sees the soul as an independent substance, clearly and decisively separated from the body. For Plotinus, only this reflects the true Platonic theory, which he prefers to Aristotle’s hylomorphic account. Building on this insight, Remes emphasizes that Neoplatonic philosophy as a whole, unlike Alexander or Aristotle, prefers top-down explanations and thus rejects any attempt at bottom-up progression. Their separation of form as substance, and thus the soul, from matter ultimately goes so far as to claim that the soul no longer resides in the body or in any particular place. In its radical approach, this perspective ultimately goes beyond what can be considered strictly hylomorphic, especially in how it challenges the concept of how the soul can interact with the body under such conditions. This question is particularly pressing in the realm of perception, which Tuominen addresses in depth in her essay. She begins with the familiar debate over the proper understanding of perception in Aristotle’s De anima, framed in terms of “spiritualism” and “literalism” by Sorabji and Burnyeat. Tuominen argues, however, that neither term is fully consistent with the Neoplatonic approach as seen in the works of Philoponus and Pseudo-Simplicius. Instead, Tuominen identifies elements of both views in the work of each author.
The book then moves beyond ancient philosophy into the realm of medieval philosophy, first approaching the hylomorphic account through the lens of the Arabic tradition. The first author that Peter Adamson considers here is Avicenna who offers a fascinating perspective on hylomorphism, in part because of his background as a physician, much like Galen. Again, the focus is on the causal efficacy of form and whether forms can be individualized through their causal effects. Following this, Stephen R. Ogden’s essay examines Averroes and argues that Averroes espoused a version of what Ogden calls liberal hylomorphism, according to which the connection between form and matter is more liberal and thus offers the possibility of explaining how a separate intellect can unite with our own cognitive powers (pp. 316-17). As Ogden shows, liberal hylomorphism builds on Aristotle’s ideas but goes decisively beyond them. In his essay, Christopher Shields addresses two fundamental questions that arise when hylomorphism is applied to the union of soul and body. The first is how a general entity, such as a form, can also be something particular, such as an individual soul. The second is how something that exists as an independent substantial form can simultaneously serve as the form of a body. Shields, through Aquinas, answers the first question in the affirmative, stating that the soul can indeed be both a form and an individual entity. However, it does not qualify as substance in the strict sense of a self-subsisting thing.
The final two essays, by Dominik Perler and Lilli Alanen, bring the discussion into the early modern period, providing a fitting conclusion to the volume. Perler begins by examining Descartes’ interpretation of hylomorphism, which differs significantly from the traditional Aristotelian view. This divergence raises the question of the specific form of hylomorphism to which Descartes might be referring. Perler traces this back to Suárez, who serves as an important bridge between Descartes and the Aristotelian tradition. Suárez’ approach, however, is particularly influenced by his predecessors Duns Scotus and William of Ockham, for whom matter is not merely potential but has a real existence. But this conception of prime matter has direct implications for understanding the relationship between body and soul. As a result, Suárez’ view can now be better understood in terms of a “composition thesis” (p. 368), showing that the position Descartes criticizes has little in common with Aristotle’s actual view.
The historical account of hylomorphism ends with the discussion of Descartes, although it could have been extended to explore how the concepts of form and matter developed after Descartes and well into the eighteenth century. Kant, for example, refers to form and matter in his Critique of Pure Reason, categorizing them as “concepts of reflection” thus conceiving of them as methodological instruments of reason. However, Charles’ choice to end with Descartes’ view is well-considered, as it underscores how hylomorphism becomes a contentious issue in discussions of soul and body when the Aristotelian distinction between potentiality and actuality in the form-to-matter relation is set aside.
In conclusion, this volume stands out as an impressive achievement in the field of ancient, late antique, and medieval philosophy. While it gathers contributions from many leading scholars, Charles has skillfully woven these diverse perspectives into a cohesive whole. Each chapter, with few exceptions, builds meaningfully on the last, creating a book that is both challenging and rewarding to engage with. This volume can therefore be highly recommended to anyone who wishes to gain a broader perspective on fundamental developments in the history of Western philosophy.
Authors and Titles
An Introduction to the History of Hylomorphism: From Aristotle to Descartes – David Charles
- Epicurean Materialism – Alexander Bown
- Stoics and Hylomorphism – Brad Inwood
- The Octopoid Soul: Stoic Responses to Aristotle’s Soul-Body Hylomorphism – Christof Rapp
- Alexander of Aphrodisias and the Stoics: Blending, Forms, and the Upwards Story – Reier Helle
- Galen on the Form and Substance of the Soul – Patricia Marechal
- Alexander of Aphrodisias’ Emergentism: Hylomorphism Perfected – Victor Caston
- Alexander of Aphrodisias on the Ancient Debate on Hylomorphism and the Development of Intellect – Frans A.J. de Haas
- Plotinus on Hylomorphic Forms – Riccardo Chiaradonna
- Strengths of Embodiment in Neoplatonism – Pauliina Remes
- Philoponus and Alexander in Historical Context on Relations between Matter and Form Inside and Outside Philosophy of Mind – Richard Sorabji
- Hylomorphism in Neoplatonic Commentaries on Aristotle?: Perception in Philoponus and Pseudo-Simplicius – Miira Tuominen
- Natural, Artificial, and Organic Forms in Avicenna – Peter Adamson
- Averroes, Intellect, and Liberal Hylomorphism – Stephen R. Ogden
- Hoc Aliquid: Aquinas’ Soul Is This Something – Christopher Shields
- Suárez’ Compositional Account of Substance – Dominik Perler
- Descartes’ Mind-Body Holism and the Primacy of Experience – Lilli Alanen