Classifying Difference and Value: The Metaphysics of Kinds and the Search for the Good in Plato’s Philebus

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This dissertation argues that the Philebus advances Plato’s late method and metaphysics as part of the ethical project at the heart of the dialogue: acquiring knowledge of the good. It demonstrates how Plato uses his method of collection and division, its corresponding metaphysics of kinds, and a teleological natural philosophy to continue his exploration of a science or expertise in living well familiar from dialogues like the Republic and Protagoras. Moreover, it puts Plato in conversation with topics in contemporary metaphysics, philosophy of science, and social philosophy. In chapter 1, I defend an interpretation of Plato’s view about the metaphysics and epistemology of kinds, in order to make sense of the first challenge he puts to the hedonist. At the start of the Philebus, Socrates calls attention to the ways that, although pleasure is one thing, there are many different pleasures, claiming that this makes it possible for some pleasures to be good, while others are bad. Many scholars have been underwhelmed by this objection, with some influential commentators labeling it a ‘trap’ and ‘naked sophism’. I defend Socrates’ objection by arguing that it introduces a technical notion of difference in kind that has important parallels to the contemporary concepts of ‘determinable’ and ‘determinate’ kinds. For example, color is a determinable kind that has determinate sub-kinds like red, which is in turn determinable in relation to scarlet and maroon. I argue that Plato deploys a technical notion of difference that is akin to the difference between determinates like scarlet and maroon. On this view, sub-kinds differ from each other with respect to their shared, unifying properties, so that the superordinate kind cannot be evaluated independently of the sub-kinds. In light of this special notion of difference, a hedonist cannot defend their identification of pleasure and the good without knowing every way sub-kinds of pleasure differ from each other. In chapter 2, I defend a novel interpretation of the method of collection and division that Plato deploys in the Philebus. In order for the hedonist to meet his challenge, Socrates introduces a method of inquiry, gifted from the Titan Prometheus, and responsible for the creation of the crafts through its ability to determine the ‘natural’ number and arrangement of sub-kinds in a domain of expertise. I argue that in order to understand this method and the specific use the hedonist has for it, we need to situate it in the broader context of Plato’s natural philosophy. Whereas some are inclined to think that natural kinds, such as carbon element and deciduous tree, exist independently of human beings, in contrast to so-called ‘social kinds’ that depend on humans, such as zoning map and ethnic enclave, Plato’s teleological conception of nature as the product of divine craft diminishes the boundaries between natural and social kinds. Plato understands the natural world, such as the structure of animal bodies, as the result of intelligent gods reasoning through how to make the most intelligent cosmos. I argue that the Promethean method is a human tool for doing something similar: transforming the ‘material’ of a domain of inquiry into a useful schematization for a craft, thereby both expressing human intelligence and supporting intelligent development and institutionalization. It does this by mapping the relationships of causal interdependence necessary for the production of some object of craft, of which Plato has a broad and inclusive understanding, onto a scheme of super- and sub-kinds, which can then be taught across generations (e.g., as an alphabet). In the context of the Philebus, this method could be used to prove that pleasure is the good, if its use to count sub-kinds of pleasure resulted in the creation of a craft of living well. In chapters 3-4, I extend my arguments from chapters 1 and 2 to Plato’s adjudication of the ethical dispute at the heart of the Philebus: whether pleasure is the source of human happiness or, if not, what the structure of a happy life is, including pleasure’s place in it. In chapter 3, I respond to the view of some scholars that Socrates, after introducing the Promethean method, fails to deploy it in the dialogue in a meaningful way. In response, I argue that Socrates replaces the initial project of determining a pleasure-based expertise in living well with one of determining the actual expertise in living well, which takes the mixture, that is, the life combining pleasure and knowledge, as its object. As a result, Socrates goes on to count the number and arrangement of sub-kinds in the mixture within the framework of the Promethean method. In chapter 4, I respond to the view of some scholars that Socrates provides an account of pleasure using the Promethean method, but in a deficient way that fails to satisfy the standards of the method. Against this, I defend two core claims. First, Socrates’ division of pleasure into true and false allows him to identify bad pleasures. This is because, by defining pleasure as the perception of an animal’s restoration to its natural condition, Socrates is able to identify defective pleasures in the form of pleasures that involve failures on the part of our cognitive and phenomenal systems for detecting restorative processes. In particular, many false pleasures misrepresent the extent to which a certain activity is regenerative of our nature; as a result, the perception of the underlying process is problematic for our ability to maintain our natural constitution. Second, I defend this position against the objection in the literature that Socrates does not present a unified account of pleasure. Drawing on the Timaeus, I argue that each of the so-called ‘pure’ pleasures conforms to the model of pleasure as a feature of the restoration of an animal’s natural condition. Their distinction is that they involve the restoration of the human being’s natural condition as a rational animal with an immortal and intelligent psychic part. In chapter 5, I briefly sketch some of the issues surrounding Socrates much shorter discussion of knowledge. I argue that his account conforms to the interpretations I defend in chapters 1-4. He collects knowledge together as a determinable domain, united by the use of the knowledge-creation practices of measuring, counting, and weighing. Although each form of knowledge uses these practices for the sake of grasping the truth, only the purest form of knowledge, dialectic, perfectly instantiates this epistemic relation. This mirrors the way that each pleasure is for the sake of the natural harmony, but they differ with respect to how, such that only the purest pleasures perfectly instantiate the teleological relation characteristic of pleasure as such.

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247 pages


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Division; Ethics; Metaphysics; Philebus; Plato


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Kamtekar, Rachana

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Brennan, Tad
MacDonald, Scott C.

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Ph. D., Philosophy

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Doctor of Philosophy

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dissertation or thesis

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