Aristotelian Plato, Mathematical Pythagoreanism and the Origins of Philosophy

Interview by Richard Marshall.

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'Pythagoras appears to have believed that 'all is number' - that everything in the world has a specific numerical value, or, as I think, that everything in the world can be understood as possessing the properties of numbers in relation to one another (i.e. ratios).'

'Plato was impressed by the Persians and Egyptians, and in antiquity he was thought to have traveled to meet them in his youth (and, on his death bed, a Chaldean came to gain wisdom from him). Plato wrote eloquently about the wisdom of Egypt in the Timaeus-Critias, ascribing the wisdom of his distant ancestor Solon of Athens to the Egyptians, and he praises the wisdom of the Persian kings Cyrus and Darius in the Laws. He also wrote about the Zoroastrian educational system, and in particular Ahura Mazda (who was the primary god of the Zoroastrian pantheon), in the First Alcibiades, which he praised in various ways, but ultimately considered deficient to the system of Socratic/Platonic education that he was advancing. Quite interestingly, as soon as Plato dies, his students in the Academy (especially his amanuensis Philip of Opus, and another figure called Hermodorus of Syracuse) claim that Plato took his overall metaphysical system from the Persians - a striking claim that, when compared with the surviving inscriptions from Persia and the Zoroastrian writings, which are collected under the title Avesta, show impressive connections.'

'While I do not go so far as to think Aristotle was more 'Platonic' than 'Aristotelian', as some people might say, I do think there is a lot of overlap between and positive contributions that each philosopher can make to the other's systems. '

Phil Horky is currently at work on three major research projects: Pythagorean Philosophy, 250 BCE to 200 CE: An Introduction and Collection of Sources in Translation (Cambridge University Press) a source book and translation of the philosophical texts and testimonies that constituted Pythagorean philosophy after its dissolution in the mid-4th Century BCE: Prelude to the Categories a monograph on the development of categorical speculation regarding existence and ways of describing it in Greece prior to Aristotle (from the Presocratics to the Early Academy): Aristotle on the Human Good: Selections from Nicomachean Ethics and Eudemian Ethics (with Monte Ransome Johnson, UCSD) a book-length student edition and commentary of some of the most famous and important texts of Aristotle. Here he discusses what mathematical Pythagoreanism is and Aristotle's division of types, Hippasus of Metapontum, the Lyceum and the early Academy, ‘exoteric’ Pythagoreans, Epicharmus’ ‘Growing Argument’ and how 'number' was understood, the essential relationship between the cosmos and the human being, how Plato and Pythagoras share common ground, Plato and wisdom practitioners from Persia, the contrast between wisdom practitioners and Greek ethics, bringing to light neglected history of ideas regarding the origins of philosophy and Plato's interest in empirical, proto-scientific knowledge.

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[Plato and Aristotle]

3:AM:What made you become a philosopher?

Phil Horky:It's difficult to provide a brief account what drew me into philosophy. I discovered philosophy quite late in my studies, in 2004, after I had completed my doctoral coursework in Classics at the University of Southern California. From my undergraduate and MA studies (at the Universities of Michigan and Chicago, respectively), I had developed into a literature scholar, with specialization in ancient Greek poetry (chiefly Homer and Euripides). I remember clearly, however, when the tools of literary study were proving insufficient to explain Socrates' arguments in Plato's Gorgias - a text which, in antiquity, was itself used as a protreptic to philosophy.

While training as a Classicist, I was exposed to those Platonic dialogues that respond well to literary approaches (especially Symposiumand Phaedrus), but I became fascinated with those dialogues whose content could not be explained away by appeal to literary tools - and especially with Platonic philosophical method, which resists easy hermeneutic approaches. I took a directed reading course with a Hellenist, William G. Thalmann, on Plato's later dialogues, where we read Sophist, Statesman, and Parmenides together in Greek over a semester. On my own, I read Theaetetusand Philebus, and dabbled in Aristotle's Metaphysics, Poetics, and Politics. I discovered quickly that I would never be going back to literature for its own sake and decided to commit my efforts to finding an ancient philosophy topic suitable to a PhD in Classics: the Pythagoreans, who are an historiographical quagmire, and whose contributions to philosophy were being overlooked by some recent scholars whose historiographical and anthropological approaches were denying their importance to philosophy. With an eye on Plato's Republic, I focused on Pythagorean political philosophy and its metaphysical entailments in the PhD thesis - an ambitious and overzealous project that thankfully has never been published as such (I'm proud of saying that the monograph version of this project, Plato and Pythagoreanism(Oxford, 2013) does not contain a single sentence from the 2007 PhD thesis).

Subsequent to the doctorate, I took up a 3-year postdoctoral fellowship at Stanford, where I worked with Chris Bobonich, who helped me greatly by showing me the ropes in philosophy, and Andrea Nightingale, whose flexible and wide-ranging approach to ancient philosophy still astonishes me. While at Stanford, I also got to know several other ancient philosophers who have had a deep and long-lasting impact on my work: A.A. (Tony) Long in Berkeley, who trained an impressive number of very strong ancient philosophers throughout his career (including both Chris and Andrea), and Monte Johnson in San Diego, who, along with Mariska Leunissen at UNC-Chapel Hill, showed me why Aristotle is so absolutely fundamental (hint: one must read the biological works). I also sought to learn ancient mathematics by reading the works of Wilbur Knorr and Ian Mueller, and by conversing with Reviel Netz and especially Henry Mendell at California State - Los Angeles. My philosophical skills were honed at the meetings of the West Coast Aristotelian Society, where I had the pleasure of watching Julius Moravcsik in action, before his passing in 2009.

By the time I took up my permanent lectureship in Durham in 2010, I had been exposed to the best that the West Coast could offer for ancient philosophy, and this was surprisingly helpful for navigating the academic communities in the UK and on the Continent. I found very supportive communities of ancient philosophers in Europe and established strong relationships with many colleagues here, most notably my senior colleague in Durham George Boys-Stones, Mauro Bonazzi in Milan (now Utrecht), and, among many other heroes in Cambridge, Malcolm Schofield.

Looking back roughly a decade after the doctorate, I see that working on the Pythagoreans was a hasty and perhaps ill-advised initial move into philosophy, since the material is so desperately obscure and riddled with so many challenges. It is the kind of work someone should undertake at the end, not the beginning, of a career. I take comfort that one of my aforementioned heroes, Myles Burnyeat, also started his career by working on the Pythagoreans (in an article 'Time and Pythagorean Religion', Classical Quarterly 12.2 (1962)) - and quickly moved on. I've been slower to do so, although most of my current work has little to do with early Pythagoreanism, focusing instead on Aristotle, Plato's Academy, and the history of Platonism.

Plato and Pythagoreanism

3:AM:You’re an expert in the relationship between Plato and the mathematical Pythagoreanism. What do you say ‘mathematical’ Pythagoreanism means and why does Aristotle’s division of types of knowledge become important here?

PH:'Mathematical' or 'Scientific' (μαθηματικός) Pythagoreanism is a specific declension of Pythagorean philosophy that was considered heretical in antiquity because it democratized Pythagorean learning. The philosophers who can be included in this group are important because they were the first to publicize and explain Pythagorean doctrines, which were enigmatic and kept for the in-group (the 'acousmatics'), by appeal to the practices of philosophy and science. Aristotle was the first to describe this schism in the Pythagorean school, and he mapped his own notions of the divisions of enquiry (into the 'what' and the 'why') onto the two groups (the 'acousmatics' and the 'mathematicians').

3:AM:Who was Hippasus of Metapontum and why is he important in this connection between Plato and Pythagoreanism?

PH:Hippasus was a first-generation Pythagorean who is famous for having discovered the relationship between musical harmony and arithmetical ratio through experimentation; he is, hence, one of the very first scientists (in a modern sense). He is important to the story of Plato and Pythagoreanism because he was considered the progenitor of 'mathematical' Pythagoreanism, the first heretic who surrendered the secret Pythagorean doctrines to the public (including eventually Plato) and caused the schism within the school. He is also associated with a democratic revolution among the Pythagoreans in Metapontum, where the Pythagoreans had a strong community and where (according to one tradition) Pythagoras died. From this perspective, he is a celebrated hero to the 'mathematical' Pythagoreans, and an wicked apostate to the 'acousmatic' Pythagoreans.

3:AM: How is Aristotle’s position on this reflected in the treatment of the Pythagoreans by other contemporary historians and philosophers, in particular those of the Lyceum and the early Academy?

PH:This is a challenging and tricky question. It would appear that as soon as the Pythagorean philosophical communities dissolved, in the middle of the fourth century BCE, historians and philosophers began to vie with one another in a bid to situate earlier Pythagoreanism. Especially prominent here were the figures associated with Plato's Academy, chiefly Speusippus of Athens, Xenocrates of Chalcedon, and Heraclides of Pontus - the latter of which, for example, argued that Pythagoras was the first to call himself a 'philosopher'. Many of these figures wanted to see Pythagoreanism, and especially the 'mathematical' species, as a precursor to Plato's own philosophy - to make Plato a Pythagorean. Similarly, Aristotle and his student Theophrastus wanted to write Pythagoreanism into the history of philosophy, as it was being formulated for the first time in a systematic way. I would say that Aristotle's position on the Pythagoreans (properly understood through the lens of Aristotelianism) is generally confirmed by what others were saying at the time, although this is a controversial statement that I have fought hard to defend in my first book.

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[Timaeus of Tauromenium]

3:AM:You introduce the idea of ‘exoteric’ Pythagoreans via your investigation into Timaeus of Tauromenium. What is this and what is your new account of mathematical Pythagoreanism that comes from all this?

PH:'Exoteric' Pythagoreans are, in my estimation, broadly the same as 'mathematical' Pythagoreans - two different words to refer to the same people. The 'exoterics' are those who publicized (and hence democratized) Pythagorean doctrines, as contrasted to the 'esoterics' or 'acousmatics', who kept them for the in-group and were aristocrats. Timaeus of Tauromenium (not to be confused with the authoritative speaker in Plato's Timaeus, who was from Epizephyrian Locri) was a late-fourth century BCE historian from Tauromenium, in Sicily, who presents a very nuanced account of Early Pythagoreanism, helped (or so I argue) by access to civic documents from city-states in South Italy that have not been preserved until today. Moreover, this Timaeus had access to Aristotle's writings when he went to Athens in the late fourth century BCE and used them in writing his own history of the Pythagoreans, who lived in South Italy and Sicily. He adapted Aristotle's accounts of 'mathematical' Pythagoreanism to his own accounts of 'exoteric' Pythagoreanism, by focusing on specific figures like Empedocles and Epicharmus, in addition to Hippasus. His is a political account of Early Pythagoreanism, to be compared with Aristotle's philosophical account.

3:AM:What is the significance of Epicharmus’ ‘Growing Argument’ for the way Plato and Pythagoras understood ‘number’and how does Plato approach it in the early and middle dialogues, especially Euthyphroand Cratylus?

PH:Pythagoras appears to have believed that 'all is number' - that everything in the world has a specific numerical value, or, as I think, that everything in the world can be understood as possessing the properties of numbers in relation to one another (i.e. ratios). The 'mathematical' Pythagoreans were fascinated by this claim and set to explaining it in various ways. One figure who undertook this was, somewhat surprising to our ears, a writer of comedies from Sicily named Epicharmus, who was very well regarded as a philosopher by Plato and Aristotle, and as an 'exoteric' Pythagorean by Timaeus of Tauromenium, who publicized the Pythagorean doctrines in comedic form. Epicharmus wrote a dialogue, only fragmentary now, in which two figures are arguing about a debt that was arranged at a prior time to be paid off. One figure (B.) argues that the person whom his interlocutor (A.) borrowed the money from was not him (B.), but rather someone else (B.*). The argument rests on the idea that personal identity, as grounded in persistence of matter or number, is not stable over time, because we're always growing older or smaller. It's an excellent example of how comedy exploits philosophy, and in doing so generates more philosophy (one could compare with the issues of personal identity and memory explored in The Good Place). Epicharmus' 'Growing Argument' was justly famous in antiquity, provoking responses from Plato (especially in the Cratylus, where he investigates the problem of persistence across time as a problem of language, and in the Phaedo, where he tries to ground the persistence of numerical properties in a metaphysics of the Forms).

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[Epicharmus]

3:AM: Is it in the Phaedothat Plato presents his most extensive evaluation of ‘number’ and in so doing gives us a sight of the way he both appropriated and superseded the Pythagoreans? Can you sketch for us what goes on here?

PH:My idea is that the Pythagoreans only understood individual humans to have numerical properties in a limited way, which doesn't have much impact beyond the question of personal identity, but that, in the Phaedo, where Socrates engages with two Pythagorean interlocutors (Simmias and Cebes, who were from the Pythagorean town of Phlius and students of the famous Pythagorean Philolaus of Croton), Plato attempts to adapt the Pythagorean notion of number to new ends. For Plato's entire argument for the immortality of the soul - which is very much an argument in favour of the persistence of psychic identity - requires him to posit the idea of contraries, which he finds most usefully and obviously exemplified in the relations between even and odd numbers. It would appear that Philolaus had already experimented philosophically with the relations of even and odd, but Plato uses them by analogy to think about the ways in which life and death relate as contrary properties, and how we can go from being alive to dead to alive again without the basic aspects of our psychic identity being altered. This is analogous to the way in which an object can retain its identity as an object whether it has six or seven parts, i.e. whether it takes on one contrary (evenness) or another (oddness).

3:AM:How does Plato disguise his critical responses to the Pythagoreans in his middle and later dialogues?

PH:My pet hypothesis is that ancient philosophers, above all Plato and Aristotle, tended not to refer to those peers of theirs whom they're attacking by name. So, when Aristotle wants to attack his contemporary competitors Speusippus or Xenocrates, he typically refers to him as 'some people', quite possibly because everyone in the room already knows exactly whom he's attacking. We still do this today, by the way. Similarly, but more frustratingly, Plato also likes to refer to his friends whose ideas he's taking to task with quirky and obscure phrases, such as 'the Heracliteans', or 'the Friends of the Forms' - surely these phrases are tinged with a sense of humour, and often said with affection (humour in ancient philosophy is especially difficult to detect). Moreover, with figures whose thought he wishes to appropriate in a positive way, he very seldom mentions them by name - for example, he never mentions Democritus by name, despite the fact that he appeals in various ways to Democritus' celebrated physics and cosmology in the Timaeus. Instead, he appeals to mythological characters in order to mask the real target - in the case of the mathematical Pythagoreans, or so I think, he avails himself to philanthropists who were punished for revealing the deepest secrets of knowledge, especially Prometheus, who gave fire and technology to mankind.

3:AM: And how did Plato transform the insights of the mathematical Pythagoreans into arguments about the essential relationship between the cosmos and the human being?

PH:Figuring out exactly what the mathematical Pythagoreans thought about the cosmos is not as difficult as inferring their take on the human being; that's because their theory of the cosmos is well documented by Aristotle and survives in fragments of, among others, Philolaus of Croton. One thing that seems to be consistent across the board is that because they committed to the principle that all things are, or have, number, they understood all things in numerical relations to one another. Those numerical relations could be internal (i.e. the parts of the human body, relative to one another), or external (i.e. the human itself in relation to his environment). Plato took this important insight and applied it both to the constitution of the human soul, which gives order to the individual, and to the constitution of the world-soul, which permeates the entire ordered universe. Both are created according to harmonic ratios, which makes them analogous, and this formulation allows Plato to argue that the human being who creates a proper concord in his soul can accordingly live in concert with the universe. The extent to which this analogizing of the human with the cosmic psyche is Early 'Pythagorean' is debatable - I tend to doubt that it is.

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[Pythagoras]

3:AM:Does the theory of reduction to first principles via imitation give us an example of how Plato and Pythagoras share common ground? Can you sketch what this argument is regarding the distance between first principles and everything else, and it’s significance?

PH:This is the 64-million pound question, for which I can only advance tentative thoughts. Aristotle is to blame here, since, in Metaphysics I, he states (without too much fuss) that Plato and the Pythagoreans had essentially the same metaphysics, which understood the relationship between sensible objects and the first principles to be one of, respectively, 'participation' and 'imitation': for Plato, sensible objects take their identity and name from the Form they participate in (e.g. this table is a table and is called 'table' by virtue of participation in the Form of the Table), and for the Pythagoreans, this table is a table by virtue of imitation of the numerical formula that is unique to tables (although this description is controversial). Ultimately, both systems are supposed to keep going up in the process of metaphysical reduction by one over many: for Plato, the most primary first principles would appear to have been the One and the Indefinite Dyad (or the One and the Many, or the One and the Greater and the Lesser - there are several ways of formulating this), from which all other things are generated; and for the Pythagoreans, they would appear to have been the Limit and the Unlimited, which either are, or are responsible for generating, numbers, and on and on down the chain of being (again, controversial).

3:AM: How involved was Plato with wisdom practitioners from Persia? Can you say what these practitioners were , how influential they were on Greek philosophy and why they have been undervalued since Diogenes Laertius?

PH:Diogenes Laertius is the most important historian of philosophy to survive from antiquity. If we didn't have his work on the Successions of the Philosophers, our knowledge would be very impoverished concerning various branches of ancient philosophy, especially Stoicism and Epicureanism. But he was not a particularly talented philosopher (nor yet a decent poet - take a look at any of the poems he writes to honour those whom he writes about). At the beginning of his work, he sketches a history of philosophy that posits the origins of philosophy in the writings of the Ionians and the Pythagoreans, without seriously considering the contributions made by, among others, the Babylonians, Persians and Egyptians. In this, he sets the standard for many modern assumptions about the origins of philosophy - that it was 'born' in Greece and Italy, and that it established itself in contrast to the irrational religious fervor of peoples from the East, etc. All of this had a terribly detrimental effect on the history of ancient philosophy, and it is all the more surprising since this was not the consensus view in antiquity (which held that the Greeks borrowed philosophical and technological ideas from the Babylonians, Persians, and Egyptians - and this view has been confirmed by, for example, Mesopotamian cuneiform tablets).

In particular, Plato was impressed by the Persians and Egyptians, and in antiquity he was thought to have traveled to meet them in his youth (and, on his death bed, a Chaldean came to gain wisdom from him). Plato wrote eloquently about the wisdom of Egypt in the Timaeus-Critias, ascribing the wisdom of his distant ancestor Solon of Athens to the Egyptians, and he praises the wisdom of the Persian kings Cyrus and Darius in the Laws. He also wrote about the Zoroastrian educational system, and in particular Ahura Mazda (who was the primary god of the Zoroastrian pantheon), in the First Alcibiades, which he praised in various ways, but ultimately considered deficient to the system of Socratic/Platonic education that he was advancing. Quite interestingly, as soon as Plato dies, his students in the Academy (especially his amanuensis Philip of Opus, and another figure called Hermodorus of Syracuse) claim that Plato took his overall metaphysical system from the Persians - a striking claim that, when compared with the surviving inscriptions from Persia and the Zoroastrian writings, which are collected under the title Avesta, show impressive connections. For example, Ahura Mazda's name translates to 'Lord Intelligence' - a remarkable parallel to Plato's notion of the demiurgic god who produced the world as 'Mind' or 'Intelligence' (Νοῦς). The Zoroastrians posited a cosmic confrontation between Truth (Asha) and Falsehood (Druj) which worked itself out in individual ethics. Much more work on comparisons between Persian thought and Early Greek philosophy needs to be done, but it requires knowledge of (at least) Old Persian, Avestan, Greek and Latin.

3:AM: One contrast between wisdom practitioners and Greek ethics is between Aristotle’s ethics amongst unequals that aims at moderation and the wisdom practitioners idea of ‘extreme proportional benefaction’. Can you explain the contrast and the role of Herennius Pontius the Samnite in this?

PH:Another area of ancient philosophy where we know far too little is early Italy. For despite the fact that it was considered by Diogenes Laertius one of the founts of philosophy, the evidence is too scarce and difficult to attain to form a complete picture of what the native 'Italic' philosophy really was (especially as it related to the dominant philosophy of the time in the Italic peninsula, Pythagoreanism, which was imported from Samos). But there are some scattered indications.

One curious account concerns a philosopher called Herennius Pontius, who was a Samnite (the sworn enemies of the Romans in the fourth and third centuries BCE) and a philosopher of ethics, whose story was known by Cicero and may have been told by one of Aristotle's students, Aristoxenus. It would appear that Aristoxenus described Pontius meeting with the great Pythagorean philosopher and statesman, Archytas of Tarentum, to discuss ethics. Interestingly, Pontius argues, contra Archytas, Aristotle and Plato (who supported an ethics of moderation) in favour of an ethics of extreme reciprocation, in which, for example, if someone confers an extreme benefaction, this should also be returned with en equally extreme benefaction (and vice versa with extreme injury). In the case of Pontius, this is played out in international politics, and in particular with notions of 'friendship' between states. For Aristotle, in order to preserve a friendship between unequal people, the superior person should receive a larger share of honor and the inferior person should receive a larger share of profit. Such a proportioning, which Aristotle refers to as proportioning 'according to worth', distinguishes between two types of reward and things for which each reward is the proper response: honour is the gift appropriate for excellence and benefaction, whereas the advantage bestowed by the superior man is a 'protection from deficiency' for the inferior man.

If we apply this Aristotelian theory to Samnite international politics, as Pontius does, an extreme benefaction offered by a superior to an inferior state will, at least theoretically, cause the latter to honour the superior state, allowing for the flourishing of a friendship. Similarly, an extreme injury will case the most complete form of enmity, which paradoxically still preserves respect among the warring states.

For Herennius, either extreme approach is to be preferred to attempting to find a 'middle-ground' with a foreign enemy - a theory that is borne out in the case of Roman-Samnite politics, in which the middle-ground attempt to resolve the dispute concludes in the Romans ultimately losing all respect for the Samnites and proscribing all of them (rather than becoming allies, or at least agreeing to a truce). The final consequence of such an action was the total annihilation of the Samnite peoples under the Roman general Sulla in the early first century BCE - a sort of Samnite holocaust which effectively ended the existence of a native 'Italic' philosophy.

3:AM: Does your work show that many views about the ancient Greeks are rather distorted or at least partial, and that key influences and more esoteric forces were in play than has been allowed for?

PH:I think that much of my earlier work sought to elaborate a more broadly informed history of philosophy, which aimed to challenge so-called 'standard' or 'consensus' views on the subjects mentioned by concentrating on aspects of ancient philosophy that have often been explained away or ignored by modern scholarship. I'm less interested in esoterism, for the simple fact that exegetically humans are better at filling in gaps with whatever their convictions tell them than allowing those cognitive spaces to exist without clear definition. I am now more at ease with suspending judgment than I used to be, and I can leave the dark places of wisdom to themselves.

Another major change that has occurred over the years is that I am now less driven to find and illuminate those obscure corners of ancient philosophy, and more interested to elucidate those core areas that are, in my opinion, sadly suffering neglect as well. For example, I worry tremendously that in our study of Aristotle we continue to ignore many of the works that are not typically part of the 'canon' of Aristotle - as if all we needed to understand Aristotle was selections from his Nicomachean Ethicsand Physics(as Philosophers might think) or his Politicsand Poetics(as Classicists might think). Moreover, I worry about the somewhat arbitrary boundaries set for ancient philosophy by Philosophers and Classicists, with Philosophers tending not to learn to read ancient philosophy in Greek, or in historical context, and Classicists only reading the works that are of relevance to literary, cultural, and historical studies, whilst neglecting the philosophy that figures like Aristotle sought so desperately to give shape.

3:AM:Does this connection with the mathematical Pythagoreans show that Plato was interested in reconciling empirical knowledge with mathematical knowledge, and that therefore empirical, proto-scientific knowledge was of great interest to Plato despite appearances to the contrary?

PH:Absolutely. In fact, we scholars have our own myths to live by as well, and one of them is that Plato was anti-scientific. This misunderstanding of Plato's philosophy aims at presenting a narrative in which Plato is the arch-Realist and Aristotle the arch-Empiricist. Neither statement is in any simple sense true, and these great philosophers were in some ways not so dissimilar. If one dares to go beyond the confines of Plato's Republic- to the later dialogues of Plato (especially the Sophist, Statesman, Philebus, and Laws), one sees a Plato that looks to our eyes more 'Aristotelian' - a Plato who is deeply interested in the divisions of knowledge, scientific explanation, taxonomies, and applied philosophy; and contrariwise, if one is willing to take seriously the fragments of Aristotle's so-called 'exoteric' works, such as the dialoguesProtrepticusor On Philosophy, or the Categories, one will see a more Platonic Aristotle, who, while not quite accepting the Forms of the Middle Dialoguesas such, nonetheless shows deep appreciation for and consideration of eternal, stable entities. While I do not go so far as to think Aristotle was more 'Platonic' than 'Aristotelian', as some people might say, I do think there is a lot of overlap between and positive contributions that each philosopher can make to the other's systems. And this is borne out when we examine the philosophical practices in the Academy after Plato's death, where Plato's successors Speusippus and Xenocrates found creative ways to integrate innovations in philosophy and science advanced by Aristotle in the articulation of their own Platonist philosophical systems. In my opinion, it is easy to fall into the trap of assuming these figures were 'dogmatic' in an un-philosophical way, when they were deeply engaged in profound philosophical disputes of the age. Like Aristotle, they were actors in the main; it's an accident of history that their works were lost.

3:AM: And finally, are there five books you can recommend to the readers here at 3:AM that will take us further into your philosophical world?

PH:Five books that remain on my desk (and hence in my consciousness) at all times:

The Presocratic Philosophers