Works In Progress

Negative Predication in Parmenides’ Third Antinomy

The focus of this paper is the second part of the Parmenides. Parmenides, in this part of the dialogue, demonstrates a form of dialectical training that should enable Socrates to grasp the truth with authority (Prm. 136b6-c5; cf. 135d3-6). When this happens, Socrates can save the theory of Forms from the criticisms of the dialogue’s first part (Prm. 135b5-c4). How does Parmenides’ Third Antinomy (Prm. 160b-164b) help Socrates achieve this end? I argue that this section of argument distinguishes at least two meanings or significations (sēmeion) of the phrase mē estin, “is not.” On the first, if something is not, then it has no being at all. On the second, if something is not, this means only that it is not identical with the nature of being, with Being itself. As support for my interpretation of the Third Antinomy, I show how it marks the beginning of an analysis of negative predication that is central to understanding the development of Plato’s thought both in and after the Parmenides. For instance, central to the account of genuine speech and thought found in the Sophist is saying of things both how they are and how they are not. Parmenides’ Third Antinomy begins to show how to accomplish the latter.

Proclus and Parmenides’ Likeness Regress

This paper focuses on a well-known response to Parmenides’ criticism of Socrates’ third account of participation (Prm. 132d1-133a7), an account that describes the relation between the Forms and their participants as a relation of “resemblance” (eikōn), “likeness” (homoios), and “modeling” (eikazon). The response is found in the fifth-century CE Neoplatonist Proclus’ commentary on the Parmenides, as well as later authors. Proclus claims that Parmenides misconstrues the relation between the Forms and their participants: Parmenides describes the relation as symmetrical, when in fact it is asymmetrical. Some scholars still champion this general response, though they different in their explanations of the asymmetry between the Forms and their participants. Proclus’ own explanation, however, has been misunderstood, and I aim to correct this. The correction is not just of historical interest, though. It turns out that Proclus’ explanation has implications for an altogether different response to Parmenides’ criticism: that Socrates is confused about relations, and therefore that the Form of Likeness—and perhaps other relational Forms too—should not be included in Plato’s ontology. I show that even if Socrates is confused about relations, it is not necessary to expunge the Form of Likeness. Rather, as Proclus himself does, we can redefine its role and thereby rescue Socrates’ third account of participation.

Life and Lifeforms in Early Greek Atomism

This paper is a collaboration with Caterina Pellò. Our paper concerns how, if at all, the Atomists distinguish different kinds of living things. The question is challenging because the Atomists, like several other Presocratics, claim that all living things—including plants—possess reason and understanding. We explain this claim by arguing, first, that that the atomists’ theory of the soul does not offer criteria that sharply separate different kinds of living things, or even living things from non-living things. Second, we show that the Atomists equate thought, sensation, and soul, and therefore make little or no distinction between being ensouled, perceiving, and thinking—which in turn challenges distinctions among plants, non-human animals, and humans. Finally, we examine the surviving evidence of the Atomists’ embryology, arguing that because all living things come to be through the same reproductive process and are made of atoms identical in kind, the Atomists can attribute to them similar physical and mental capacities.


While each Form is what it is to be F, some Forms also instantiate F (or “self-instantiate”). This paper argues that the explanation for a Form’s instantiating F should be that the Form participates in itself. First, I motivate the need for an explanation of self-instantiation by reviewing a problem for the theory of Forms from the Parmenides, as well as the section on the Great Kinds from the Sophist. Second, I consider the advantages and disadvantages of self-participation alongside an alternative explanation—that the Form’s being what it is to be F is sufficient to explain its instantiation of F. I argue that because the theory of Forms does not require multiple explanations for instantiation, self-participation is the preferable explanation for why a Form instantiates F. On my view, the explanation for instantiation is always participation, whether or not the participant or the object participated in are different.

Speech, Thought, and the Interweaving of Forms

There is an intimate connection between speech and thought for Plato. In fact, they are essentially the same thing (Soph. 263e; cf. 264a-b, Tht. 189e-190a). There is also an important connection between speech and thought, on the one hand, and the Forms, on the other (Prm. 134e-135c). Specifically, all speech and thought depends on the interweaving of Forms with each other (Soph. 259e). Why is the interweaving of Forms with each other necessary for all speech and thought? Some scholars offer a “semantic answer,” proposing that all speech and thought is about or “contains” Forms. As Ackrill was among the first to explain, “human discourse is possible only because the meanings of general words are related in definite ways; it is essential to language that there be definite rules determining which combinations of words do, and which do not, constitute significant sentences” (1965, 204). Yet this approach cannot be correct. I offer an alternative answer that stresses the metaphysical requirements for speech and thought. Briefly, my account concentrates on the structuring role that some Forms play in the intelligible and sensible realms. The weaving together of the structuring Forms is a necessary condition for all speech and thought. Were this condition not satisfied, there would be nothing at all.