  The Phaedo is Plato's eulogy to Socrates. It recounts the last hours of Plato's teacher. Socrates/Plato wants to convince us that we should care about our souls and that the best way to care for the soul is to live philosophically. Towards that end we find a series of arguments whose aim is to prove the immortality of the soul. At least three of these arguments, the Argument from Recollection and its prelude (65a-67a and 72e-78b), the Affinity Argument (78b-84b), and the Final Argument (102a-107a) and its prelude (95a-102a), are crucial for understanding Plato's initial thoughts on metaphysics and epistemology. Here Plato draws a contrast between unchanging Forms and changing material particulars. Unfortunately, neither in the Phaedo nor in any other dialogue do we find Plato giving a detailed description of the nature of Forms, or particulars, or their interaction. What is referred to as Plato's theory of Forms is thus a rational reconstruction of Plato's doctrine. In such a reconstruction scholars try to determine a set of principles or theses which, taken together, allow us to show why Plato says what he does about Forms, souls, and other metaphysical items. In the attempt to make more precise what Plato is after, one risks attributing to Plato notions that are either not his or not as well developed in Plato as scholars would hope. Perhaps the notion of a particular is such a case. Intuitively, particulars are things like my dog Ajax, Venus, my computer, and so on, the ordinary material things of the everyday spatio-temporal world. (But we also speak of particular actions, particular events, particular souls, and much else.) In a rational reconstruction, we can be more precise by stipulating, for instance, that a particular is that of which properties are predicated and which is never predicated of anything (or anything other than itself). This ‘stipulated definition’ is nowhere in Plato, though it may well capture his thinking about ordinary particulars. For the sake of exposition, I will assume that in the Phaedo Plato is appealing to our naïve, intuitive understanding of what it is for something to be a material particular. In the author's opinion, the metaphysics of the Phaedo and other middle period works is devoted to developing the account of Forms; perhaps because while most of us think that included in what there is are the various, e.g., dogs, people, mountains and trees, few of us ever think about whether there is some universal/Form, Justice Itself, The Large Itself, and so on, that exists outside of space and time. (In the late dialogues, especially the Timaeus and Philebus, Plato attempts to give a systematic account of material particulars.)