Workshop in Ancient Philosophy Week 8 MT17

Ancient Philosophy

The School of Athens

Speaker: Simon Shogry (Brasenose College) 

Title: 'Appearance and Assertion in Plato and Aristotle' 


In this paper I explore a disagreement between Plato and Aristotle concerning the role which reason plays in generating our 'perceptual appearances' (phantasiai). According to the view we find in Plato's late dialogues, to undergo a perceptual appearance requires the mind to make an assertion (apophasis) concerning the relationship between the perceptible objects in one's surroundings. Humble as this psychological achievement may sound, Plato will nevertheless insist that it requires the mind to call upon the most advanced resources at its disposal, i.e., the peculiarly rational power to discern how this perceptible object is similar to, or different from, others like it. Such a view is commonly attributed to Plato on the basis of Socrates's final refutation of the identity of perception and knowledge in the Theaetetus. My approach, however, emphasizes a different set of Platonic texts -- primarily the Sophist and Cratylus -- in which Plato sketches a demanding theory of the psychological preconditions for making any assertion. I suggest that by focusing on Plato's claim that perceptual appearances involve assertion, we can better understand not only his own motivations for identifying perceptual appearance as an opinion (doxa) of a certain kind, but also Aristotle's criticism of this identification, which he expounds at length in the De Anima. On my reading, what Aristotle is objecting to in Plato's treatment of phantasia is his insistence that it involves an assertion of a kind which presupposes the activity of reason. But for Aristotle, "perceptual appearance is other than assertion" (DA 3.8, 432a10-12), and so is available to guide the behavior of animals lacking reason but engaging in perception.


Convenors: Dr Karen Margrethe Nielsen, Prof Ursula Coope, and Dr Luca Castagnoli

Webpage: Workshop in Ancient Philosophy

List of site pages