I argue that Democritus presents a theory of colour in which the predominance of atomic shapes and microstructural arrangements are necessary but not sufficient for colour vision. Focusing primarily on Democritus’ basic colours, I analyse his microstructural account, providing a new analysis of the natural and technological underpinnings of his method of explanation. I argue that the notion of predominance allows Democritus to account for both the variation and the repeatable correspondence of colour perception by setting limits on possible microstructures. This account, however, is complicated by the evidence for a Democritean theory of colour transformation and distorted vision, which arise from a dynamic interplay of features at the level of microstructures and at the level of perception.
The hypothesis formulated by Usener and Diels that Theophrastus’ De sensibus is a crucial source of relevant sections of the Placita is insufficiently supported by the evidence. Of the fifteen Placita chapters dealing with sense perception and cognition, only a few are related to the treatise.
It is well known that when it comes to perception in the De anima, Aristotle uses affection-related vocabulary with extreme caution. This has given rise to a debate between interpreters who hold that in Aristotle’s account, the act of sense-perception nevertheless involves the physiological alteration of the sense organ (Richard Sorabji), and those think, with Myles Burnyeat, that for Aristotle, perception does not involve any material process, so that an Aristotelian physics of sense-perception is a “physics of forms alone”. The present article suggests that the dematerialisation of Aristotle’s theory of perception, which has a long story from Alexander of Aphrodisias to Brentano, may be in fact traced back to Theophrastus’ exegesis of Aristotle’s relevant passages in the De anima in his Physics, as we can reconstruct it on the basis of Priscian’s Metaphrasis in Theophrastum and Simplicius’ commentary of Aristotle’s De Anima. The reconstruction also provides a scholastic-theoretical frame to Theophrastus’ critical exposition of ancient theories about sense perception in his De sensibus, whether or not the discussion originally belonged to Theophrastus’ Physics.
This paper considers Theophrastus’ use in the De sensibus of the principles that like perceives like and that unlike perceives unlike to criticise his predecessors. It is argued that the aporiai that arise from either position serve to motivate the view of perception articulated by Aristotle in the De anima.
As a crucial source for Presocratic theories of sense perception, Theophrastus’ De sensibus deserves a closer scrutiny than the placement among A-fragments, as often suggested or instigated. This paper proposes to refine our terminology for labelling the varying quality of reporting within the A-fragments has. It supplements the existing criticism of Diels’ division by analysing neglected features. A reassessment of the assumptions underlying the terms ‘fragment’ and ‘paraphrase’ can contribute to dissolving the sharp distinction between A- and B-fragments in DK. It advocates, not equality for A-fragments, but a more inclusive and accurate evaluation of the passages.
Many fragments from Theophrastus on perception are preserved by the late Neoplatonist, Priscian of Lydia. After preliminary source criticism concerning how to identify the fragments, I turn to Theophrastus’ discussion of perceiving and perceptual awareness. While he clearly rejects literalism, he also does not embrace “spiritualism”: he argues instead that we receive the defining proportions of perceptible qualities in the sense organ, though in different contraries than in the perceptible (thereby avoiding literalism). If Priscian’s report is faithful, Theophrastus also accepts a moderate capacity reading of De anima III.2, locating awareness in a central monitoring sense, common to the individual modalities; and this has further implications for the unity of consciousness. Theophrastus’ method, though aporetic in form, is nonetheless a constructive engagement with the same texts of Aristotle’s we have ourselves, in the service of a joint research program in psychology that he shared with his colleague and former teacher.
In paragraphs 5 and 86 of the De sensibus Theophrastus gives a brief report of Plato’s views on the sense of vision and its object, i. e. colour, based on the Timaeus. Interestingly enough, he presents the Platonic doctrine as a third alternative to the extramission and intromission theories put forward by other ancient philosophers. In this article I examine whether or not Theophrastus’ account is impartial. I argue that at least some of his distortive departures from the Platonic dialogue are due to his Aristotelian inheritance, even though they do not always represent Aristotle’s expressed views.