The Brute Within:

Appetitive Desire in Plato and Aristotle

(Oxford University Press, 2006)

Paperback edition, 2009

Read the digital version at Oxford Scholarship Online.


Plato’s Republic introduces and employs an elaborate psychological theory whose core commitment it is that human motivation comes in three forms: rational, spirited, and appetitive. The Brute Within offers a detailed philosophical analysis of appetitive motivation and of Plato’s conception of appetite as a part of the soul. In doing so, it explores both the psychological theory of the Republic and its afterlife in Plato’s later dialogues as well as in Aristotle’s psychology and ethics. It shows that Plato’s Timaeus, a relatively late dialogue, preserves the substance of the Republic’s conception of appetite as a distinct part of the soul. At the same time, the Timaeus offers a number of important clarifications and amplifications of the theory of the tripartite soul, whose full significance emerges once the Timaeus is read in the context of a number of other later dialogues, most importantly the Theaetetus and the Philebus. In turning to Aristotle’s psychological theory and moral psychology, the book calls attention to the remarkable continuity between Aristotle’s and Plato’s thought in this area. It shows how Aristotle made Plato’s psychological theory his own both by modifying it where appropriate and by giving it a more determinate and precise formulation.

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Articles and book chapters

  1. Bullet “Aristotle’s analysis of akratic action,” in The Cambridge Companion to Aristotle’s Nicomachean Ethics, ed. Ron Polansky (forthcoming)

  2. Bullet “The cognition of appetite in Plato's Timaeus,” in Plato and the Divided Self, edd. Rachel Barney, Tad Brennan and Charles Brittain (forthcoming)

  3. Bullet “Posidonius on the nature and treatment of the emotions,” in Oxford Studies in Ancient Philosophy 40 (Summer 2011), 189–211

  4. Bullet “Virtue of character in Aristotle’s Nicomachean Ethics,” in Oxford Studies in Ancient Philosophy XXXVII (Winter 2009), 177–212

  5. Bullet  “Nicomachean Ethics VII.4: Plain and qualified akrasia,” in C. Natali (ed.), Symposium Aristotelicum: Aristotle’s Nicomachean Ethics, Book VII (Oxford University Press, 2009), 72–101 

  6. Bullet “Plato on the soul,” in Gail Fine (ed.), Oxford Handbook on Plato (Oxford University Press, 2008), 243–66

  7. Bullet “Zur Bewegung der Lebewesen bei Aristoteles,” in Klaus Corcilius and Christof Rapp (eds.), Beiträge zur Aristotelischen Handlungstheorie (Stuttgart: Franz Steiner Verlag, 2008), 53–64

  8. Bullet “The assimilation of sense to sense-object in Aristotle,” in Oxford Studies in Ancient Philosophy XXXIII (2007), 179–220

The paper argues that Aristotle's mature theory of perception in the De Anima assigns prominent explanatory roles both to a technical notion of assimilation of sense to sense-object, according to which such assimilation is identical with perceiving, or with perceiving considered in a certain way, and to assimilation of a more ordinary kind, in which one thing (such as the sense-organ in question) comes to be like another by taking on one of its features in a straightforward way. If this is along the right lines, neither Burnyeat's spiritualism nor Sorabji's (or Everson's) literalism does justice to Aristotle's conception of the likeness between perceiver and sense-object in the act of perception.

  1. Bullet “The analysis of the soul in Plato’s Republic,” in Gerasimos Santas (ed.), The Blackwell Guide to Plato’s Republic (Oxford: Blackwell, 2006), 146–65

(The volume is reviewed here by Richard Kraut for NDPR.)

  1. Bullet “Desire and reason in Plato’s Republic,” in Oxford Studies in Ancient Philosophy XXVII (2004), 83–116

(The volume is reviewed here by John Dillon for BMCR.)

  1. Bullet “Ancient theories of soul,” in The Stanford Encyclopedia of Philosophy (Winter2003 E Edition), Edward N. Zalta (ed.) 


Book reviews

  1. Bullet Review of Pavel Gregoric, Aristotle on the Common Sense, Rhizai VI.2 (2009), 225–31

  2. Bullet Christopher Bobonich, Plato’s Utopia Recast: His Later Ethics and Politics, in Philosophical Review, Vol. 113, No. 4 (October 2004), 560–6
    Available at Philosophical Review Online: pdf.

  3. Bullet Andreas Kamp, Philosophiehistorie als Rezeptionsgeschichte. Die Reaktion auf Aristoteles’ De Anima-Noetik. Der frühe Hellenismus, in Journal of the History of Philosophy XLI:1 (January 2003), 122–3

Available to Muse subscribers: html, pdf.

Hendrik Lorenz