In Nicomachean Ethics 1.6, Aristotle directs his criticism not only against the Platonic Idea of the Good but also against the notion of a universal Good. In this paper, I also examine some of the most interesting aspects of his criticism of the Platonic Good and the universal Good in Eudemian Ethics 1.8. In the EN, after using a series of disputable ontological arguments, Aristotle’s criticism culminates in a strong ethical or rather practical and, simultaneously, epistemological argument, from which a (...) dialectical postulatum emerges. This argument aims to show that we have to discover the dialectical stages or grades which constitute the relation between the ultimate End, i.e., the Good simpliciter or the absolute Good, and the relational goods till the last prakton good in which each specific praxis ends. According to the present reading, Aristotle sets out to establish a kind of Dialectic of the ends or Dialectic of the goods, which puts emphasis on the descent to the specific good, which is appropriate to and cognate with each individual, be that a person, praxis, science or craft. It is also suggested that this might be relevant to Aristotle’s tendency to establish a separation of phronēsis, i.e., practical wisdom, from sophia, i.e., wisdom, in the Nicomachean Ethics. (shrink)

In Metaphysics B.2 and M.2, Aristotle gives a series of arguments against Platonic mathematical objects. On the view he targets, mathematicals are substances somehow intermediate between Platonic forms and sensible substances. I consider two closely related passages in B2 and M.2 in which he argues that Platonists will need intermediates not only for geometry and arithmetic, but also for the so-called mixed mathematical sciences, and ultimately for all sciences of sensibles. While this has been dismissed as mere polemics, I show (...) that the argument is given in earnest, as Aristotle is committed to its key premises. Further, the argument reveals that Annas’ uniqueness problem is not the only reason a Platonic ontology needs intermediates. Finally, since Aristotle’s objection to intermediates for the mixed mathematical sciences is one he takes seriously, so that it is unlikely that his own account of mathematical objects would fall prey to it, the argument casts doubt on a common interpretation of his philosophy of mathematics. (shrink)

This paper presents a new interpretation of the objects of dianoia in Plato’s divided line, contending that they are mental images of the Forms hypothesized by the dianoetic reasoner. The paper is divided into two parts. A survey of the contemporary debate over the identity of the objects of dianoia yields three criteria a successful interpretation should meet. Then, it is argued that the mental images interpretation, in addition to proving consistent with key passages in the middle books of the (...) Republic, better meets those criteria than do any of the three main positions. (shrink)

I argue here that a properly Platonic theory of the nature of number is still viable today. By properly Platonic, I mean one consistent with Plato's own theory, with appropriate extensions to take into account subsequent developments in mathematics. At Parmenides 143a-4a the existence of numbers is proven from our capacity to count, whereby I establish as Plato's the theory that numbers are originally ordinal, a sequence of forms differentiated by position. I defend and interpret Aristotle's report of a Platonic (...) distinction between form and mathematical numbers, arguing that mathematical numbers alone are cardinals, by reference to certain non-technical features of a set-theoretical approach and other considerations in philosophy of mathematics. Finally I respond to the objections that such a conception of number was unavailable in antiquity and that this theory is contradicted by Aristotle's report in Metaph . XIII that Platonic numbers are collections of units. I argue that Aristotle reveals his own misinterpretation of the terms in which Plato's theory was expressed. (shrink)

In a 1985 article entitled “The Art of Glaukos,” Diskin Clay suggested that the enigmatic passage at the beginning of the geological myth in Phaedoreferred toRepublic10, where the soul is likened to the sea-creature Glaucus whose true nature, like the soul’s, is obscured by the distortions imposed by underwater life. Starting with a defense of Clay’s ingenious suggestion, my purpose is to compare Phaedoto Glaucus, with its true nature obscured by traditional assumptions about the order in which Plato composed his (...) dialogues, and thus how they should be read. At least part of the reason that Clay’s thesis has not been embraced is because it clashes with the dogma that Phaedocannot refer back to Republic; I want to challenge that dogma. Borrowing from Catherine Zuckert the notion that, since Phaedocomes at the end of Socrates’ story, it can usefully be read as the culmination of the Platonic dialogues, I will show how a “late” Phaedo—i.e., a reading of the dialogue that is open to the possibility that it refers to more than one dialogue generally considered to be later than it with respect to composition—recovers its true nature, presently encrusted with the oysters and seaweed of an outdated developmentalism that has obscured this culminating masterpiece of Plato’s dramatic and philosophical art. (shrink)

Once we realize that the indivisible and infinitely repeatable One of the arithmetic lesson in Republic7 is generated by διάνοια at Parmenides 143a6-9, it becomes possible to revisit the Divided Line’s Second Part and see that Aristotle’s error was not to claim that Plato placed Intermediates between the Ideas and sensible things but to restrict that class to the mathematical objects Socrates used to explain it. All of the One-Over-Many Forms of Republic10 that Aristotle, following Plato, attacked with the Third (...) Man, are equally dependent on Images and above all on the Hypothesis of the One. (shrink)

This doctoral thesis addresses a group of conceptual instruments that are central to Aristotle's philosophy, namely, the concepts of pros hen, homonymy, synonymy and multivocity. These instruments are crucial to many of Aristotle's works as he devotes himself to analysing the key notions in each of his investigations using these instruments. Despite the undisputable importance of these instruments, they display severe interpretative problems, which this thesis critically evaluates. The currently established view on the relationship between homonymy and multivocity is discussed (...) and then reassessed in order to approach the definition of the so-called pros hen structure. This approach takes into account a so-far undescribed distinction of types of examples Aristotle uses and sheds new light on the assessments of the role of the pros hen structure in Aristotle’s philosophy and the theories on development in Aristotle’s thought. Niels Tolkiehn studied Philosophy and Systematic Musicology at the University of Hamburg. He continued his studies as a doctoral student at the Munich School of Ancient Philosophy, a graduate school of the Ludwig-Maximilians-Universität München. Supervised by Prof. Dr. Christof Rapp, he was awarded his doctoral degree in 2019 with this dissertation. (shrink)