Plato: Philosophy of Science

At Timaeus 48e2–52d4 Timaeus sets out to establish that there are three principles or kinds underlying the creation of the cosmos, not just the two he acknowledged earlier. The way he does so is not simply by adding an account of the third kind to the accounts of being and becoming that he has already given. Rather he does so by showing how each of the three differs from the others. It has not been noticed how this procedure structures the (...) receptacle passage. The passage divides up into three parts, each punctuated by a list of the three kinds in a significant order. If we take X, Y and Z to stand for ‘becoming’, ‘being’ and ‘receptacle’ ’ respectively, the structure is X≠Z, X≠Y, Y≠Z. By showing the distinctness of each pair, Timaeus demonstrates that all the kinds are distinct and that they are indeed three in number. (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)

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)

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.

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)

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)

Plato's comments on astronomy and the education of the guardians at Republic 528e ff have been hotly disputed, and have provoked much criticism from those who have interpreted them as a rejection or denigration of observational astronomy. Here I argue that the key to interpreting these comments lies in the relationship between the conception of enquiry that is implicit in the epistemological allegories, and the programme for the education of the guardians that Plato subsequently proposes. We have, I suggest, been (...) too eager to stress the similarities here, when recognition of the differences may supply us with the tools required for a better understanding of 528e ff, one that to a large extent disarms the anti-empirical critique. My discussion proceeds in three stages. Firstly, Plato takes great care to place his comments on astronomy in the context of the preceding epistemological allegories. Is there any evidence here, where Plato might be thought to discuss enquiry in general, that he rejected or denigrated observation? I argue that even if Plato advocated a 'Two Worlds' (TW) ontology, he still envisaged a dynamic process of enquiry, interrelating sensibles and intelligibles, the investigation of each being necessary but not sufficient to achieve the overall aim. Secondly, Plato appears to be deriving how we ought to go about educating the guardians from how we ought to conduct our enquiries. While the two are intimately related there are important differences, recognition of which turns the supposed rejection of observation into an affirmation of the need for an initial empirical approach. I contend that this makes good sense of the internal structure of 528e ff, and of its relations to other parts of the Republic. Thirdly, I discuss the Republic in relation to the evidence offered by later works on the question of astronomy and observation, and raise the question of whether Plato's views on the imperfection of the sensible world necessarily lead to the denigration of careful and prolonged empirical work. (shrink)

Plato's dialogue the Timaeus-Critias presents two connected accounts, that of the story of Atlantis and its defeat by ancient Athens and that of the creation of the cosmos by a divine craftsman. This book offers a unified reading of the dialogue. It tackles a wide range of interpretative and philosophical issues. Topics discussed include the function of the famous Atlantis story, the notion of cosmology as 'myth' and as 'likely', and the role of God in Platonic cosmology. Other areas commented (...) upon are Plato's concepts of 'necessity' and 'teleology', the nature of the 'receptacle', the relationship between the soul and the body, the use of perception in cosmology, and the work's peculiar monologue form. The unifying theme is teleology: Plato's attempt to show the cosmos to be organised for the good. A central lesson which emerges is that the Timaeus is closer to Aristotle's physics than previously thought. (shrink)

In one of the most disputed passages of Greek literature Plato in the Republic, 7. 528e–530c prescribes astronomy as the fourth study in the education of the Guardians. But what sort of astronomy? According to one school of thought it is a purely speculative study of bodies in motion having no relation to the celestial objects that we see. While this interpretation has rejoiced the hearts of Plato's detractors, who regard him as an obstacle to the progress of science, it (...) has dismayed his admirers. Another school of thought holds that what Plato meant was that astronomers must get to know the real motions of the heavenly bodies as opposed to their apparent motions as seen by us on earth. The opposed interpretations may be set out in the following representative citations from Sir Thomas Heath and John Burnet. (shrink)

The figure of the cordial host of the Academy, who invited the most gifted mathematicians and cultivated pure research, whose keen intellect was able if not to solve the particular problem then at least to show the method for its solution: this figure is quite familiar to students of Greek science. But was the Academy as such a center of scientific research, and did Plato really set for mathematicians and astronomers the problems they should study and methods they should use? (...) Our sources tell about Plato's friendship or at least acquaintance with many brilliant mathematicians of his day (Theodorus, Archytas, Theaetetus), but they were never his pupils, rather vice versa -- he learned much from them and actively used this knowledge in developing his philosophy. There is no reliable evidence that Eudoxus, Menaechmus, Dinostratus, Theudius, and others, whom many scholars unite into the group of so-called "Academic mathematicians," ever were his pupils or close associates. Our analysis of the relevant passages (Eratosthenes' Platonicus, Sosigenes ap. Simplicius, Proclus' "Catalogue of geometers", and Philodemus' "History of the Academy", etc.) shows that the very tendency of portraying Plato as the architect of science goes back to the early Academy and is born out of interpretations of his dialogues. (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 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)

Unitarianism was the norm amongst ancient interpreters of Plato. One strategy they used to maintain the unity of his thinking was to argue that different works were saying the same things but in different modes. So, for example, the Republic was saying ethically what the Timaeus was saying in the manner of natural philosophy. In this paper, I want to offer an interpretation of the Cave image in Republic 7 which lends support to this division of labour, and so indirectly, (...) at least, to a unitarian understanding of Plato’s thinking across these two works. (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)

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.

In this paper, I examine three significant periods of the cosmological argument which exemplify the importance of contestation: first, Plato’s and Aristotle’s formulation of it, second, Philoponus’ own reactions and influence, third, the contemporary state of such discourses. Contestation has an inestimable role in philosophical development and reflection, as will be demonstrated through the examination of such periods.

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)

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.

Plato’s invention of the metaphor of carving the world by the joints gives him a privileged place in the history of natural kind theory in philosophy and science; he is often understood to present a paradigmatic but antiquated view of natural kinds as possessing eternal, immutable, necessary essences. Yet, I highlight that, as a point of distinction from contemporary views about natural kinds, Plato subscribes to an intelligent-design, teleological framework, in which the natural world is the product of craft and, (...) as a result, is structured such that it is good for it to be that way. In Plato’s Philebus, the character Socrates introduces a method of inquiry whose articulation of natural kinds enables it to confer expert knowledge, such as literacy. My paper contributes to an understanding of Plato’s view of natural kinds by interpreting this method in light of Plato’s teleological conception of nature. I argue that a human inquirer who uses the method identifies kinds with relational essences within a system causally related to the production of some unique craft-object, such as writing. As a result, I recast Plato’s place in the history of philosophy, including Plato’s view of the relation between the kinds according to the natural and social sciences. Whereas some are inclined to separate natural from social kinds, Plato holds the unique view that all naturalness is a social feature of kinds reflecting the role of intelligent agency. (shrink)

This paper 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)

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)

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)

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)

This volume explores the intuitive yet puzzling concept of teleology as it has been treated by philosophers from the time of Plato and Aristotle to the present day. Philosophical discussions are enlivened and contextualized by reflections on the implications of teleology in medicine, art, poetry, and music.

Plato's dialogue the Timaeus-Critias presents two connected accounts, that of the story of Atlantis and its defeat by ancient Athens and that of the creation of the cosmos by a divine craftsman. This book offers a unified reading of the dialogue. It tackles a wide range of interpretative and philosophical issues. Topics discussed include the function of the famous Atlantis story, the notion of cosmology as 'myth' and as 'likely', and the role of God in Platonic cosmology. Other areas commented (...) upon are Plato's concepts of 'necessity' and 'teleology', the nature of the 'receptacle', the relationship between the soul and the body, the use of perception in cosmology, and the work's peculiar monologue form. The unifying theme is teleology: Plato's attempt to show the cosmos to be organised for the good. A central lesson which emerges is that the Timaeus is closer to Aristotle's physics than previously thought. (shrink)

In his opening speech, Timaeus argues that the cosmos must be the product of a craftsman looking to an eternal paradigm. Yet his premises seem at best to justify only that the world could have been made by such a craftsman. This paper seeks to clarify Timaeus’ justification for his stronger conclusion. It is argued that Timaeus sees a necessary role for craftsmanship as a cause that makes becoming like being.

Plato’s demiurge makes a series of questionable decisions in creating the world. Most notoriously, he endeavors to replicate, to the extent possible, some of the features that his model possesses just insofar as it is a Form. This has provoked the colorful complaint that the demiurge is as raving mad as a general contractor who constructs a house of vellum to better realize the architect’s vellum plans (Keyt 1971). The present paper considers the sanity of the demiurge’s reasoning in light (...) of Timaeus 32c5-33b1, where he invokes considerations of wholeness, completeness, uniqueness, and eternality in deciding to build the body of the world from all of each of the simple bodies. Since the passage makes no appeal to the demiurge’s intelligible model, one can mine it for indications of the value that the demiurge takes those features to have independent of mimetic goals. I argue that, for Plato, those features are intrinsically good-making and, thus, that it is not only appropriate for them to characterize Forms qua Forms but also that it is appropriate for the demiurge to aim at replicating them, to the extent possible, in his creation. In particular, I argue that the demiurge’s success in instilling a circumscribed version of each feature in his creation helps to qualify it as a genuine being despite the fact that it comes to be. (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)

Gregory Vlastos has argued that Aristotle and other commentators on the Phaedo have mistakenly interpreted Plato’s Forms to be efficient causes. While Vlastos is correct that the Forms by themselves are not efficient causes, because of his neo-Kantianism he has misunderstood the close connection between the Forms and the explanation of change, including teleological change. This paper explores the connection in Plato’s Phaedo between the Forms, the nature of change, and efficient causality, and argues that Aristotle’s remarks are not as (...) misplaced as Vlastos claims. (shrink)

A Critical Notice of Thomas KjellerJohansen, Plato’s Natural Philosophy. A Study of the Timaeus-Critias.

This paper is an investigation of the place of rhetoric in Plato's judgement that philosophers must rule. The possibility that rhetoric could facilitate the rule of philosophy raises the question of whether rhetoric could also be used to undermine the governance of philosophy. It is my thesis that Plato argues for understanding rhetoric as limited in its ability to function at cross-purposes to those of philosophy because of a basic and direct relationship between the effectiveness of rhetoric and its ability (...) to promote the ends of its audience. In the Phaedrus, we are told that persuasion requires rhetors to comprehend the nature of their audience so that appropriate methods of persuasion may be employed. This dependence on the nature of its subject is extended to include that subject's ends, an understanding of which is the province of philosophy. Since philosophy as it is put forward in the dialogues is interested in determining and promoting proper human fulfilment, then ultimately constraining the effectiveness of rhetoric in terms of the nature of its object ties rhetoric to the philosophic agenda. (shrink)

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)