Plato: Natural Science

In this paper I examine the role of optimality reasoning in Aristotle’s natural science. By “optimality reasoning” I mean reasoning that appeals to some conception of “what is best” in order to explain why things are the way they are. We are first introduced to this pattern of reasoning in the famous passage at Phaedo 97b8-98a2, where (Plato’s) Socrates invokes “what is best” as a cause (aitia) of things in nature. This passage can be seen as the intellectual ancestor of (...) Aristotle’s own principle, expressed by the famous dictum “nature does nothing in vain but always what is best for the substance from among the possibilities concerning each kind of animal” (Progression of Animals II, 704b12-18). The paper is focused around exploring three questions that arise in connection with Aristotle’s use of this optimality principle: (1) How do we understand the concept of “the best” at work in the principle? (2) How does Aristotle conceive of “the range of possibilities”? And, finally, (3) what role does optimality reasoning play in Aristotle’s natural science? Is it a special form of demonstration in which the optimality principle functions as one of its premises, or is it a heuristic device that helps uncover those causally relevant features of a natural substances that ultimately serve as middle terms in demonstrations? In the final section I return to the comparison between Plato and Aristotle and argue that, while both see the natural world as the product of an optimizing agent and while both see this assumption as licensing a pattern of reasoning that appeals to a certain conception of “the best”, they disagree fundamentally over what the optimization agent is and how it operates. Thus, despite their general agreement, it would be a mistake to think that Aristotle simply took over Plato’s use of optimality reasoning without significant modifications. (shrink)

In the Timaeus, Plato famously acknowledges the receptacle as extremely difficult to comprehend. It is neither intelligible (which is reserved exclusively for the Forms) nor sense-perceptible (as it is a principle far too basic). Instead, as Plato proposes, the receptacle can only be apprehended through a “bastard” sort of “reasoning” (νόθος λογισμός, Tim. 52b1-2.). This paper explores an exegesis of Plato’s claim as offered by Calcidius, the 4th century translator of and commentator on the Timaeus. I identify two distinctive methods (...) Calcidius advances when grappling with the knowability of the material substratum that underpins our world. The first method – analysis (resolutio) – traces its intellectual lineage to earlier philosophical tradition, and Calcidius primarily uses it to uncover the proper nature and ontological characteristics of matter. Conversely, the second method corresponds to the only cognitive grasp of matter Calcidius believes humans are capable of. In his view, we can neither sense-perceive nor rationally understand matter. Instead, matter yields itself only to the cognitive mode of suspicion (suspicio). The paper provides a detailed analysis of Calcidius’ suspicio, delving into its intricacies and exploring the interrelationships between suspicio and resolutio. As such it offers a pioneering and comprehensive exploration of Calcidius’ account of the knowability of matter. (shrink)

This article concerns the so-called irrigation system in the Timaeus’ biology (77a-81e), which replenishes our body’s tissues with resources from food delivered as blood. I argue that this system functions mainly by the natural like-to-like motion of the elements and that the circulation of blood is an important case study of Plato’s physics. We are forced to revise the view that the elements attract their like. Instead, similar elements merely tend to coalesce with each other in virtue of their tactile (...) features as the atomists describe. The notion of attraction is replaced with this notion of mere coalescence. I begin by outlining how blood is made from food. I then argue that an understanding of health and disease compels us to read Plato as if he were an atomist and to abandon the popular scholarly interpretations according to which the elements attract each other. (shrink)

In this article, I make the case for the continued relevance of Plato’s Timaeus. I begin by sketching Allan Bloom’s picture of the natural sciences today in The Closing of the American Mind, according to which the natural sciences are, objectionably, increasingly specialized and have ejected humans qua humans from their purview. I argue that Plato’s Timaeus, despite the falsity of virtually all of its scientific claims, provides a model for how we can pursue scientific questions in a comprehensive way (...) that stresses their connections to other disciplines, including the humanities, and that puts humanity qua humanity back in the picture. I then argue that being led by Plato’s philosophy to return humanity conceptually to the natural world can improve our thinking regarding climate change and other important environmental crises. (shrink)

L'étude entend montrer que, si le temps est finalement unique, l'espace, lui, est originellement (et non du fait de la constitution de l'être-au-monde) multiple. Une analyse d'un passage du Timée où la Chôra est dite tithênê (nourrice) permet d'asseoir une interprétation de la différence foncière entre espace et lieu. Le lieu a progressivement disparu pour s'absorber dans l'espace neutre qui traduit homologiquement l'infinité divine ou pour s'atténuer dans le site. Il est difficile de trouver une analyse adéquate du lieu depuis (...) la mort de Leibniz (1916) jusqu'à la thèse de Bergson en latin sur la notion aristotélicienne de lieu. This study aims at making clear that, if, on the one hand, time is finally unique, while, on the other hand, we can say that space is in itself, and not for transcendantal reasons (the constitution of human subjectivity), a many-fold entity. By considering with great accuracy Plato's Timæus, where topos as chôra appears as tithênê (a nurse), we are able to interpret the very real distinction between space and place. Place has progressively disappeared, being absorbed in this homology of God's infinite, which is indeed Newton's neutral space, or at least being weakened in « site » (Ort). We will hardly find, between Leibniz' death and Bergson's latin thesis on aristotelician conception of topos, one correct study about place. (shrink)

Scientific observation has led to the discovery of recurring patterns in nature. Symmetry is the property of an object showing regularity in parts on a plane or around an axis. There are several types of symmetries observed in the natural world and the most common are mirror symmetry, radial symmetry, and translational symmetry. Symmetries can be continuous or discrete. A discrete symmetry is a symmetry that describes non-continuous changes in an object. A continuous symmetry is a repetition of an object (...) an infinite number of times. A consequence of continuous symmetry is the existence of conservation laws. A natural system with discrete and continuous symmetries displays several physical properties, such as the existence of long-range order. Geometric shapes exhibit symmetry as mirror reflections of each other. Symmetry in nature has been a model of beauty since the beginning of civilization. Since the earliest times, nature itself has manifestly been a model, evincing regularity in sundry forms and occurrences–from minerals and plants to the anatomy of living beings, to the regularly recurring stellar constellations. For Ancient Greek philosophers, proportion, symmetry, and harmony, were the basics to determine whether something is beautiful or not. Ancient Greek philosophers were known for bringing logic and rational thinking to phenomena that were previously explained by mythology and Gods. They observed the natural world around them and used their knowledge to answer questions about the proportion in observable objects and the origin of Earth. The Greek words _summetria_ and _summetros_ appear frequently in the Timaeus, defined as parts with each other and with the whole. Plato has a very rough concept of symmetry, and when he uses “beauty” to characterize the so-called Platonic Solids in the Timaeus, he seems to be emphasizing their regularity and indirectly their symmetry. Plato believes the four elements (earth, air, fire, water) have been constructed by the Demiurge, or a divine craftsman who appoints order in an otherwise chaotic universe. Minerals are representative examples of beauty, order, and symmetry in inorganic materials. Well-formed minerals (crystals) are a collection of equivalent faces related by symmetry. The goal of this paper is to relate the perspective of symmetry in ancient Greek philosophy with the modern scientific evidence of the geometric description of crystal structures. The five Platonic solids are ideal models of geometrical patterns that occur throughout the world of minerals. In this paper, minerals serve as a model of connecting the symmetry theory in Plato’s philosophy and modern advances in mineralogy. (shrink)

The intellectual history of evolutionary theory really does not begin in earnest until the late seventeenth/early eighteenth century. Prior to that, the idea that species might have evolved over time was not a serious possibility for most naturalists and philosophers. There is certainly no substantive debate in antiquity about evolution in the modern sense. There were really only two competing explanations for how living things came to have the parts they do: design or blind chance. Ancient Greek Atomism, for example, (...) taught that all composite bodies, including living things, are generated through the random collision of atoms as they rebel and move in the void. Plato and Aristotle both dismissed this possibility on the grounds that living things are too complex and too well-adapted to be products of chance. This eventually became the central premise in Galen’s own Argument from Design. That species forms might have gradually evolved over time by a process of natural selection was not seen as a plausible alternative. Of course, such a theory had been proposed by Empedocles in the fifth century BCE. But because his theory still relied heavily on chance, it was not taken seriously by any of the later ancient Greek or Roman thinkers. My aim in this paper is to investigate the reasons why evolutionary thinking failed to gain momentum in antiquity after its introduction by Empedocles. (shrink)

In one of the most famous but equally obscure passages in the Timaeus, Plato describes the generation of time and the heavens. The “moving image of eternity” (37d5) is commonly read as Plato’s most general characterisation of time. Rémi Brague famously challenged the traditional interpretation on linguistic grounds by claiming that Plato actually did not conceive of time as an image (εἰκών) but rather as a number (ἀριθμός). In this paper, I shall claim that this controversy is by no means (...) a modern one. The traditional interpretation is mostly owed to Plato’s most prominent reader, Plotinus, who famously conceives of time in relation to eternity (Enn. III.7.13.24-25). Brague’s alternative reading, however, is anticipated by Simplicius’ attempt to refute the Plotinian interpretation, as I shall show. According to my reconstruction, Simplicius’ reading of the Timaeus not only shows why the traditional interpretation falls short, but it also offers a systematic argument that bolsters Brague’s alternative reading. Finally, I shall show that this is consistent with Plato’s text. It shall become clear that current interpretative problems are essentially prefigured in the late ancient debate. (shrink)

This book sheds new light on Plato's cosmology in relation to Greek religion by examining the contested distinction between the traditional and cosmic gods. A close reading of the later dialogues shows that the two families of gods are routinely deployed to organise and structure Plato's accounts of the origins of the universe and of humanity and its social institutions, and to illuminate the moral and political ideals of philosophical utopias. Vilius Bartninkas argues that the presence of the two kinds (...) of gods creates a dynamic, yet productive, tension in Plato's thinking which is unmistakable and which is not resolved until the works of his students. Thus the book closes by exploring how the cosmological and religious ideas of Plato's later dialogues resurfaced in the Early Academy and how the debates initiated there ultimately led to the collapse of this theological distinction. (shrink)

This is an essay on perception and its objects in the Timaeus. Two features of this work are noteworthy. First, the emphasis throughout is on Timaeus' views and not Plato's. Second, I show how broader aspects of Timaeus' cosmology are directly relevant to his philosophy of perception.

The relationship between mind and necessity is one of the major points of difficulty for the interpretation of Plato’s Timaeus. At times Timaeus seems to say the demiurge is omnipotent in his creation, and at other times seems to say he is limited by pre-existing matter. Most interpretations take one of the two sides, but this paper proposes a novel approach to interpreting this issue which resolves the difficulty. This paper suggests that in his speech Timaeus presents two hypothetical models (...) of creation, one with an omnipotent demiurge and one where he is limited by matter, so as to investigate their theoretical and empirical validity. Further, he shows that each model is ultimately an inadequate explanation of the first principles of the cosmos. Timaeus’ speech is therefore properly understood to be aporetic: it leaves its listeners aware of the difficulties inherent in the two models of creation, but without a more viable alternative. (shrink)

In this paper I first address what I consider a central issue in the account of perception in Plato’s Timaeus, namely, how the pathemata pass through the body to reach the soul, and thus become aistheseis. My point in Section 1 is that in tackling this issue Plato aims to provide a firm physiological basis to the notion of perception that starts to emerge in the Theaetetus and the Philebus and is crucial to the late development of his theory of (...) cognition. In the ensuing section I try to put the account of perception in the Timaeus into a historical perspective, aiming to highlight two points: a) Plato’s description of the way in which sensible impressions “travel” inside the body and interact with its parts and other constituents is largely indebted to previous theories, such as those we find, for example, in Empedocles and a few Hippocratic writers; b) The leading role in this story (where internal air plays a significant supporting role) is played by blood flowing through the vascular system and thus performing a crucial cognitive function. Moreover, emphasizing the role of blood as well as analyzing the elaborate way in which perceptions are transmitted through the body to the soul proves vital to appreciate (in Section 3) the cognitive status of the lower parts of the soul (which are more involved in perception) and their relation to reason. Overall, the paper adds further elements to our understanding of Plato’s embodied approach to cognition. I had already written (and submitted) this article when Johansen (2021) was published. The latter’s approach to the role of blood in Plato’s physiology of knowledge in the Timaeus converges in part with mine (as I was pleased to find out), partly due to our overlapping sources and bibliography. (shrink)

The principles governing elemental composition, variation, and change in Plato’s Timaeus appear to be incompatible, which has led commentators to prioritize some of the principles to the exclusion of others. Call this seeming incompatibility the problem of isomorphic variants. In this paper, I develop the theory of proportionate atomism as a solution to this problem. Proportionate atomism retains the advantages of rival interpretations but allows the principles of material composition, variation, and change to combine into an internally coherent and explanatorily (...) powerful atomic physics. (shrink)

In Plato’s eponymous dialogue, Timaeus, the main character presents the universe as an (almost) perfect sphere filled by tiny, invisible particles having the form of four regular polyhedrons. At first glance, such a construction may seem close to an atomistic theory. However, one does not find any text in Antiquity that links Timaeus’ cosmology to the atomists, while Aristotle opposes clearly Plato to the latter. Nevertheless, Plato is commonly presented in contemporary literature as some sort of atomist, sometimes as supporting (...) a form of so-called ‘mathematical atomism’. However, the term ‘atomism’ is rarely defined when applied to Plato. Since it covers many different theories, it seems that this term has almost as different meanings as different authors. The purpose of this article is to consider whether it is correct to connect Timaeus’ cosmology to some kind of ‘atomism’, however this term may be understood. Its purpose is double: to obtain a better understanding of the cosmology of the Timaeus, and to consider the different modern ‘atomistic’ interpretations of this cosmology. In short, we would like to show that such a claim, in any form whatsoever, is misleading, an impediment to the understanding of the dialogue, and more generally of Plato’s philosophy. (shrink)

I argue that, according to Plato, the body is the sole cause of psychic disorders. This view is expressed at Timaeus 86b in an ambiguous sentence that has been widely misunderstood by translators and commentators. The goal of this article is to offer a new understanding of Plato’s text and view. In the first section, I argue that although the body is the result of the gods’ best efforts, their sub-optimal materials meant that the soul is constantly vulnerable to the (...) body’s influences. In the second section, I argue that every psychic disorder is a disruption of the motions of the inner psychic circles by the body; moreover, I defend my translation of 86b. In the final section, I argue that the goal of education is to restore the circles to their original orbits, and I disarm a possible objection that bad education is also a cause of psychic disorder. (shrink)

This paper concerns Plato’s characterization of the body as the soul’s tool. I take perception as an example of the body’s usefulness. I explore the Timaeus’ view that perception provides us with models of orderliness. Then, I argue that perception of confusing sensible objects is necessary for our cognitive development too. Lastly, I consider the instrumentality relationship more generally and its place in Plato’s teleological worldview.

I argue that Plato thinks that the soul has location, surface, depth, and extension, and that the Timaeus’ composition of the soul out of eight circles is intended literally. A novel contribution is the development of an account of corporeality that denies the entailment that the soul is corporeal. I conclude by examining Aristotle’s objection to the Timaeus’ psychology and then the intellectual history of this reading of Plato.

This article concerns the place of Plato’s eschatology in his philosophy. I argue that the theory of reincarnation appeals to Plato due to its power to explain how non-human animals came to be. Further, the outlines of this theory are entailed by other commitments, such as that embodiment disrupts psychic functioning, that virtue is always rewarded and vice punished, and that the soul is immortal. I conclude by arguing that Plato develops a view of reincarnation as the chief tool that (...) the gods have to ensure that virtue is victorious over vice throughout the whole cosmos. (shrink)

Marsilio Ficino’s view on ensoulment, which can be extrapolated from his critique of natal astrology, relies on the relations of metaphysical proportion between the different levels of life and being which are central to Platonic philosophy. Drawing primarily on Plotinus, Ficino describes the emergence of life in the embryo as a process in which the World Soul is the true agent. For him, the ‘human nature’ that is present in the developing embryo attracts into the mother’s womb the seed of (...) ‘human nature’ which is present in the World Soul’s vegetative power. Once channelled into the womb, the World Soul’s vegetative power animates the embryo’s body. Now endowed with organic life, the embryo becomes irresistibly attractive to the rational soul, which in this way is drawn down to it and becomes embodied. For Ficino, the moment when ‘rational’ ensoulment happens is completely irrelevant to prefiguring one’s life path, contrary to what was claimed by natal astrology. Nevertheless, it leaves an important mark on one’s physio-psychological makeup. (shrink)

Analogies between the human and the cosmos run throughout Plato’s Timaeus. Timaeus claims that the cosmos came to be as mind’s “persuasion of necessity.” This paper argues that an anthropological equivalent to this “persuasion” can be found in Timaeus’ suggestive account of the human liver. Mediating between intellect and desire, the organ shows the problem of mind and necessity reflected in the human soul.

My dissertation is a reading of Plato’s Timaeus that centers sexual difference and in particular femininity. I analyze the role of sexual difference in the framing of the dialogue as well as its accounts of body in the first and second discourse and its account of health in the third discourse. I argue that sexual difference, and, in particular, sexual reproduction, serves as a guiding paradigm of Timaeus’ entire project. I argue in each part of my dissertation that various aspects (...) of the Timaeus depend on a certain notion of sexual difference—even aspects which are seemingly causally prior to the issue of sexual difference (e.g., the nature of cause itself, structure). The dissertation consists of three parts. In the first part of my dissertation, I give a new reading of the myth of the origin of women at the end of the Timaeus and bring it into conversation with the dialogue’s opening in order to give an interpretation of the dialogue’s framing. I analyze the concept of sexual difference presented in this myth and argue that its philosophical richness has been overlooked, with many considering it to be either a joke or a sexist account. Focusing on Timaeus’s account of the woman’s relationship with her womb, I argue that womanhood in this myth is constituted by features that are elsewhere characterized as essentially philosophical (e.g., collaboration, making room, recognizing the complex structure of things, and nurture). In the second part of my dissertation, I introduce the two paradigms for the origin and composition of the cosmos in the Timaeus: the first discourse’s craft paradigm that construes the cosmos as a crafted artifact, and the second discourse’s genetic paradigm that construes the cosmos as a birthed organism. I am especially concerned with each discourse’s account of body. Here, I argue that the second discourse’s genetic paradigm is a significant revision of the first discourse’s craft paradigm. While some scholars have found that Timaeus’s insights in the second discourse are a further development of the groundwork he lays in the first discourse, I argue that the genetic paradigm’s focus on femininity and the mutual collaboration of masculine and feminine capacities is incompatible with the craft paradigm’s androcentrism. Finally, in the third part of my dissertation, I analyze the way that the Timaeus centers women’s bodies in its account of health in body and soul. Here, I argue that the Timaeus characterizes health by drawing on ideas about women’s bodies that are framed as symptoms of feminine disease in the Hippocratic texts (e.g., disequilibrium, flux, and porosity). Taken together, the three articles of my dissertation constitute a reading of the role of sexual difference in each part of the Timaeus. (shrink)

Plato’s Timaeus reveals a cosmos governed by Necessity and Intellect; commentators have debated the relationship between them. Non-literalists hold that the demiurge, having carte blanche in taming Necessity, is omnipotent. But this omnipotence, alongside the attributes of benevolence and omniscience, creates problems when non-literalists address the problem of evil. We take the demiurge rather as limited by Necessity. This position is supported by episodes within the text, and by its larger consonance with Plato’s philosophy of evil and responsibility. By recognizing (...) the analogy between man and demiurge, the literal reading provides a moral component that its non-literal counterpart lacks. (shrink)

Two of Plato’s dialogues, the Parmenides and the Timaeus, deal explicitly with the relationship between being and time. The former builds on the assumption that whatever is must be temporal, while the latter makes being and time mutually exclusive. This paper begins by examining how the argument develops in the Parmenides, specifically in the corresponding sections 140e1-142a1 and 151e3-155e3 of the first and the second deductions of the dialectical exercise, as well as in the corollary to the second deduction at (...) 155e4-157b5. It then compares this argument with the account of time given in Timaeus 37e6-39e2, which alludes to the account given in the Parmenides. In stressing the incompatibility of these two accounts, it highlights a remarkable feature they both share. Parmenides’ argument starts from the assumption that whatever is in time must be present, past or future, whether a process or a state resulting from a process. As he advances further in the game of Zenonian antilogies, however, he reduces the dimension of the present to a mere ‘now’, conceived of as a ‘stop’ in the process of becoming. In the corollary, he eventually removes the present from time the ‘instant’ in which a change between two mutually exclusive processes or states occurs. Timaeus, for his part, immediately rules out that the present is a temporal dimension, by restricting temporality to the past and the future. Thus, in both accounts, the present vanishes from time and temporal processes are made dependent on extratemporal conditions. However, Parmenides’ argument points to an extratemporal principle of indeterminacy allowing for change, while, for Timaeus, there are two extratemporal conditions for temporal processes, namely the being of the intelligible Forms, on the one hand, and a pre-cosmic, disorderly becoming in space, on the other. (shrink)

The Timaeus is perhaps the most unusual of Plato’s dialogues. In this paper, I attempt to interpret Timaeus’s strange speech, which makes up most of the dialogue. I argue that Timaeus has grasped the grave challenge posed to philosophic reason by men like Hesiod who claim that mysterious gods are the first causes of the world, and therefore one cannot say that there are any true necessities governing this world. If this is true, then philosophy, as the study of nature, (...) which depends on the existence of necessity, would be impossible. Timaeus articulates two serious attempts to meet this challenge by demonstrating the stability and rational comprehensibility of the world from solid first principles: one according to which mind is the cause of all things; another according to which everything comes to be through mindless necessity. But he ultimately suggests that neither of these attempts have been successful, thereby demonstrating the limits of natural science’s ability to meet the religious challenge. Timaeus’s speech also has a rhetorical purpose related to this failure: insofar as he finds himself unable adequately to meet the religious challenge, and yet is still attracted to and finds worthwhile the pursuit of philosophy, he thinks a rhetorical account of the cosmos is necessary to shore up faith in reason for elite and educated young men who find themselves inclined to natural science. The more rhetorical aspects of Timaeus’s speech, and above all his account of the triangles, serve this purpose. (shrink)

One short passage on what is called the Receptacle in Plato’s Timaeus has been the subject of much controversy since Cherniss presented an alternative reading of it in 1954. In this paper, I criticize an influential argument presented by Zeyl for a traditional reading, and propose a new interpretation which adopts the alternative reading on important sentences of the passage, but is not accompanied by the defects of Cherniss’ interpretation.

In Plato’s Timaeus, two different theories – the Receptacle theory and the geometrical particle theory – are presented to explain change in the natural world. In this paper, I argue that there is tension between the two theories. After examining several possible solutions for this tension, I conclude that Plato does not present it as something ready to be solved within the dialogue but, rather, as something to be understood in a way that maintains both theories. Finally, I also argue (...) that the contrast between the two theories in the Timaeus derives from a similar contrast in the Phaedo. (shrink)

I defend, against its more recent critics, a literal, factual, and consistent interpretation of Timaeus’ creation of the cosmos and time. My main purpose is to clarify the assumptions under which a literal interpretation of Timaeus’ cosmology becomes philosophically attractive. I propose five exegetical principles that guide my interpretation. Unlike previous literalists, I argue that assuming a “pre-cosmic time” is a mistake. Instead, I challenge the exegetical assumptions scholars impose on the text and argue that for Timaeus, a mere succession (...) of events and the relations derived from it (before, after, simultaneous with) imply no time, given the narrow definition of the term used in the dialogue. For Timaeus, I explain, time is measurable, regular, and dependent on the motion of the celestial bodies. A mere succession of events like the one needed to understand the creation story and the pre-cosmos requires none of these elements. Readers of Plato erroneously assume that a succession of events implies time, but that is to impose a conception of time absent in the text. The chapter offers a detailed reconstruction of the pre-cosmic stage under a literalist interpretation and argues how it is compatible with the immutable relationship between the Demiurge and the cosmos. -/- This is an open access chapter distributed under the terms of the CC BY-NC 4.0 license. chapter 4. (shrink)

I argue that Plato believes that the soul must be both the principle of motion and the subject of cognition because it moves things specifically by means of its thoughts. I begin by arguing that the soul moves things by means of such acts as examination and deliberation, and that this view is developed in response to Anaxagoras. I then argue that every kind of soul enjoys a kind of cognition, with even plant souls having a form of Aristotelian discrimination (...) (krisis), and that there is therefore no completely unintelligent, evil soul in the cosmos that can explain disorderly motions; as a result, the soul is not the principle of all motion but only motion in the cosmos after it has been ordered by the Demiurge. (shrink)

__. L’articolo analizza la descrizione della natura delle piante e la tacita giustificazione del vegetarianismo fornite da Platone nel _Timeo_. Tale pratica alimentare sembra assumere un’utilità esclusivamente fisiologica: potrebbe darsi che Platone si fosse opposto a quanti professavano il vegetarianismo in qualità di mezzo necessario per purificare l’anima e per raggiungere la felicità, come gli orfici, i pitagorici, Empedocle ma anche il suo discepolo Senocrate. Attraverso il particolare valore attribuito a una dieta vegetariana, Platone priva di validità la pretesa degli (...) altri filosofi: solo lo studio delle idee permette di ottenere la felicità. _Abstract_. The aim of this paper is to analyse Plato’s description of plants and his tacit justification of vegetarianism in the _Timaeus_. This practice seems to possess exclusively a physiological relevance: I argue that Plato is opposing the idea of vegetarianism as a superior way to purify one’s soul and achieve happiness, how it was being professed by the Orphics, the Pythagoreans, Empedocles, and even by his disciple Xenocrates. In the _Timaeus_, with the justification of vegetarianism only for physiological purposes, Plato is discrediting other philosophers’ conception of vegetarianism and perfect life: only the study of the noetic world grants ultimate happiness. (shrink)

In the present article, we consider the question of the primary elements in Plato’s Timaeus, the components of the whole universe reduced, by an extraordinarily elegant construction, to two right triangles. But how does he reconcile such a model with the infinite diversity of the universe? A large part of this study is devoted to Cornford’s explanation in his commentary of the Timaeus and its shortcomings, in order to finally propose a revised one, which we think to be entirely consistent (...) with Plato’s text. This analysis is an essential step for the understanding of the connection between the sensible world and the mathematical principles that underlies Timaeus’ cosmological account. (shrink)

In the Timaeus, human bodies are treated as homeostatic systems, striving to maintain their natural state. This striving constitutes Plato’s explanatory framework for perception: perceptions come about when the equilibrium is shaken, and when it is restored. The article makes two main suggestions: first, that experienced pleasure and pain are grounded in non-experiential departures from and restorations of the natural state. Second, that the striving to maintain the natural state grounds perceptual interests, especially through conscious algesic and hedonic affection. Explanation (...) of what humans find desirable and avoidable in their environment – what they attend to – is a complicated story that in the context of the Timaeus must include the role of human rational abilities. This article, however, only sheds light on its other, very basic aspect: the teleology involved in bodies and how it affects perceptual interests. (shrink)

Scholarship on Plato's Timaeus has paid relatively little attention to Tim. 77a–81, a seemingly disjointed passage on topics including plants, respiration, blood circulation, and musical sounds. Despite this comparative neglect, commentators both ancient and modern have levelled a number of serious charges against Timaeus' remarks in the passage, questioning the coherence and explanatory power of what they take to be a theory of respiration. In this paper, I argue that the project of 77a–81e is not to sketch theories of respiration, (...) circulation, and digestion, but to explain how the human body is maintained in light of and despite constant environmental depletion. Further, I argue that in order to understand this account of “the replenishing system,” we need to understand Timaeus' striking analogy of the fish trap or nassa. Commentators have generally focused directly on the workings of the bodily construction that Timaeus likens to a fish trap, but without considering how we should understand the analogy qua analogy. I develop a functional reading of the analogy that yields a coherent account of the replenishing system on which previous criticisms of Timaeus' remarks on respiration do not arise. Aside from lending greater unity to the passage, both internally and within its immediate context in the dialogue, this account of the replenishing system contributes to our understanding of Timaeus' reason-and-necessity explanatory framework as applied to the human body and has noteworthy implications for specific explanatory principles, in particular like-to-like motion and circular thrust. (shrink)

This paper provides a rational reconstruction of a Platonic trope bundle theory that is a live alternative to contemporary bundle theories. According to the theory, Platonic particulars are composed of what Plato calls images of Forms; contemporary metaphysicians call these tropes. Tropes are dependent on Forms and the Receptacle, while trope bundles are structured by natural kinds using the Phaedo's principles of inclusion and exclusion and the Timaeus’ geometrised elements, as well as by co-location in the Receptacle. Key elements of (...) discussion include persistence and abundance of Plato's tropes. The resulting theory is compared with contemporary trope bundle theories. (shrink)

This paper is about the history of a question in ancient Greek philosophy and medicine: what holds the parts of a whole together? The idea that there is a single cause responsible for cohesion is usually associated with the Stoics. They refer to it as the synectic cause (αἴτιον συνεκτικόν), a term variously translated as ‘cohesive cause,’ ‘containing cause’ or ‘sustaining cause.’ The Stoics, however, are neither the first nor the only thinkers to raise this question or to propose a (...) single answer. Many earlier thinkers offer their own candidates for what actively binds parts together, with differing implications not only for why we are wholes rather than heaps, but also why our bodies inevitably become diseased and fall apart. This paper assembles, up to the time of the Stoics, one part of the history of such a cause: what is called ‘the synechon’ (τὸ συνέχον) – that which holds things together. Starting with our earliest evidence from Anaximenes (sixth century BCE), the paper looks at different candidates and especially the models and metaphors for thinking about causes of cohesion which were proposed by different philosophers and doctors including Empedocles, early Greek doctors, Diogenes of Apollonia, Plato and Aristotle. My goal is to explore why these candidates and models were proposed and how later philosophical objections to them led to changes in how causes of cohesion were understood. (shrink)

This work aims to investigate the occurrences of the female lexicon, in particular γυνή and μήτηρ, in the Timaeus, to bring out Plato's position regarding women that can be deduced from the hermeneutics of the examined passages. It is necessary to consider all the problems related to Plato's writings, including the argumentative structures used and the complexity of some concepts. The occurrences in the Timaeus, although not numerically conspicuous, are significant in terms of content, given the very nature of this (...) dialogue, which aims to identify the position and role of man and his soul in the cosmos. In Timaeus’ Prologue, such as in the Republic, Plato expresses more open positions regarding the social role of women; instead in other passages, such as those dealing with the transmigration of souls, Plato uses images relating to women to help his listeners to understand very complex issues. These images, to be understandable, have to be adequate to the idea about women common to Plato’s time. (shrink)

The Timaeus is the dialogue that was for many centuries the most influential of Plato’s works. Among its readers we find Descartes, Boyle, Kepler and Heisenberg. In the first division of Timaeus Plato deals with the theory of celestial motion, in the second he presents us with the first mathematical theory of the structure of matter. Here, in a gigantic step forward with respect to the preceding Democritean atomistic theory with its unalterable micro-entities, he introduces the intertransformability of elementary corpuscles (...) and with that the first “chemical” reactions in history. Plato’s geometrical interpretation of Empedocles’ elements and his geometrical atomism is described at the molecular, atomic and sub-atomic level. The “chemical” reactions reported in Timaeus are written in the enlightening chemical symbolism, analogies with modern chemistry are noticed throughout. (shrink)

Readers of Plato since antiquity have generally taken Socrates’ intellectual autobiography in the Phaedo as a signal of his turn away from the study of natural philosophy. They have turned instead to characters such as Timaeus for evidence of Plato’s pursuit of physics. This article argues that Plato’s Socrates himself developed a philosophy of nature in his criticism of Anaxagoras and his subsequent philosophic pursuits. Socrates’ autobiography places the study of nature in a foundational position within the development of his (...) philosophic method. In the Apology, Socrates further elaborated his investigation into nature through his understanding of theology. Finally, in the Phaedrus, Socrates connects the study of nature with the study of rhetoric as tools for virtue. Therefore, Plato’s Socrates does not reject or abandon physics, as has often been suggested, but rather, he incorporates it into his own philosophic project and challenges its practitioners to connect their own inquiries with human affairs. (shrink)

In paragraphs 5 and 86 of the De sensibus Theophrastus gives a brief report of Plato’s views on the sense of vision and its object, i. e. colour, based on the Timaeus. Interestingly enough, he presents the Platonic doctrine as a third alternative to the extramission and intromission theories put forward by other ancient philosophers. In this article I examine whether or not Theophrastus’ account is impartial. I argue that at least some of his distortive departures from the Platonic dialogue (...) are due to his Aristotelian inheritance, even though they do not always represent Aristotle’s expressed views. (shrink)

At Plato’s Phaedrus 270c, Socrates asks whether one can know souls without knowing ‘the whole.’ Phaedrus answers that ‘according to Hippocrates’ the same demand on knowing the whole applies to bodies. What parallel is intended between soul-knowledge and body-knowledge and which medical passages illustrate the analogy have been much debated. Three dominant interpretations read ‘the whole’ as respectively (1) environment, (2) kosmos, and (3) individual soul or body; and adduce supporting Hippocratic passages. But none of these interpretations accounts for the (...) Phaedrus’ rhetorical method. A better reading sees the whole as the genos ‘soul,’ as the Phaedrus’ taxonomies divide that genus. (shrink)

A teleological explanation is an explanation in terms of an end or a purpose. So saying that ‘X came about for the sake of Y’ is a teleological account of X. It is a striking feature of ancient Greek philosophy that many thinkers accepted that the world should be explained in this way. However, before Aristotle, teleological explanations of the cosmos were generally based on the idea that it had been created by a divine intelligence. If an intelligent power made (...) the world, then it makes sense that it did so with a purpose in mind, so grasping this purpose will help us understand the world. This is the pattern of teleological explanation that we find in the Presocratics and in Plato. However, with Aristotle teleology underwent a change: instead of thinking that the ends were explanatory because a mind had sought to bring them about, Aristotle took the ends to operate in natural beings independently of the efforts of any creative intelligence. Indeed, he thought that his predecessors had failed to understand what was distinctive of nature, namely, that its ends work from the inside of natural beings themselves. (shrink)

This book examines the birth of the scientific understanding of motion. It investigates which logical tools and methodological principles had to be in place to give a consistent account of motion, and which mathematical notions were introduced to gain control over conceptual problems of motion. It shows how the idea of motion raised two fundamental problems in the 5th and 4th century BCE: bringing together being and non-being, and bringing together time and space. The first problem leads to the exclusion (...) of motion from the realm of rational investigation in Parmenides, the second to Zeno's paradoxes of motion. Methodological and logical developments reacting to these puzzles are shown to be present implicitly in the atomists, and explicitly in Plato who also employs mathematical structures to make motion intelligible. With Aristotle we finally see the first outline of the fundamental framework with which we conceptualise motion today. (shrink)

In this paper, I propose a new reading of Phaedo 99b6-d2. My main thesis is that in 99c6-9, Socrates does not refer to the teleological αἰτία but to the αἰτία that will be provided by a stronger ‘Atlas’ (99c4-5). This means that the passage offers no evidence that Socrates abandons teleology or modifies his views about it. He acknowledges, instead, that he could not find or learn any αἰτία stronger than the teleological one. This, I suggest, allows an interpretation of (...) the Phaedo in which Socrates offers a consistent account of the αἰτία of generation and destruction. (shrink)

Chez les interprètes récents du Timée de Platon, le terme « téléologie », inventé au xviiie siècle, a pris une place déterminante. Mais l’usage de ce terme trahit une interprétation aristotélicienne de la figure du démiurge qu’il s’agit d’assimiler au premier moteur, dans le contexte de la cause finale. On s’interrogera ici sur l’origine de ce terme, et sur la pertinence de son usage pour comprendre le rôle que joue le démiurge dans le Timée.

Beginning with a reading of Plato's Statesman, this work interrogates the relationship between life and being in Plato's thought. It argues that in his later dialogues Plato discovers--or invents--a form of true or real life that transcends all merely biological life and everything that is commonly called life.

Whatever our metaphysics of time, today we usually work with the assumption that we have one unified temporal framework, which allows for situating all events, processes, and happenings in the sense that we can put them all in a temporal relation to each other; they are all either before, after, or simultaneous with each other. In this paper, I show that for the early Greeks, by contrast, the very idea of such a unified notion of time would be foreign; instead, (...) they assume different temporal (and not necessarily comparable) struc-tures belonging to different events. And I show what effect this lack has on the quality of temporal experiences – it means that different temporal experiences are thus seen as expe-riences of genuinely different kinds. (shrink)

The paper focus is on the main methodological sets of Plato which substantially influenced his philosophic and scientific thinking, expressed in the dialogue ‘Timaeus’, as well as defined the specific of his doctrine in relation to the cosmos and human being: the principle of substantial perfection, deterministic approach, a tendency to analyze the empiric material with the means of mathematical objects. Plato’s understanding of the cosmos and human body as lively, holistic constructions enabled their fruitful systematic studies. Shaping his teaching (...) on the soul and the body of human being, Plato endeavored to solve one of the most complicated tasks: to establish the first theoretical, mathematised system, and under such conditions to fill the pure language of observations with ideal constructs. The author shows that one of the most important scientific achievements of the Athenian philosopher was the use of the thinking constructions of geometrical triangles, which made possible creating of the theoretical models of living organisms, with explaining their nature and functioning that was one among the first in the history of science. Moreover Plato was the first in the history of science who filled with the theoretical contents not the first elements only, but all the examined material objects. (shrink)

It is a puzzling fact that the Greek term for Nature ‘physis’ could be used to refer to i) reality as a whole, ii) the nature of something, iii) to individual material beings or materiality and iv) all things that are self-generating. In order to understand and tie together this wide array of possible meanings, I will consider the thesis that ‘physis’ was in fact used as a concept of being, a term naming the fundamental property of all of reality (...) in the early pre-Socratics, poets and scientists before 500 BCE. Investigating ‘physis’ in this way can give us a way of thinking about Nature as a dynamic and creative but material process that goes far beyond the classical understanding of Nature as the sum of things that self-generate or the modern mathematical understanding of Nature born with Galileo, dominant to this day. (shrink)