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209 Doctrines: Psychology the theory of air-impressions consistent with Aristotle's statement (118) that according to Democritus one could see an ant in the heavens if the intervening space were empty? (iii) how are air-impressions produced? In particular, what is the contribution of the perceiver to their production? The answers to questions i and ii are connected to one another. Clearly, if Democritus believed that the formation of air-impressions was necessary for the transmission of eidola from the perceived object to the perceiver, then one could not see an ant, or anything else, across a void. So if the answer to i is that eidola could not cross a void, but require air-impressions as a vehicle, then the answer to ii is that that theory is inconsistent with Aristotle's evidence. But it is totally implausible that Democritus should have held that eidola could not cross a void; for what could stop them doing so? Obviously, nothing. So far from its being the case that the presence of a void between perceiver and object would be an obstacle to perception (as it would in Aristotle's theory, which required a medium for the transmission of sensible forms), that situation would be the ideal condition for the transmission of eidola, since there would be no intervening atoms to disrupt or deflect them. And that is surely the point of Aristotle's remark; given a situation where there is no obstacle to the eidola, even the tiniest object at the greatest possible distance would be seen with perfect clarity.39 What, then, is the role of air-impressions? Broadly speaking, they are posited as part of an account of visual perception in the non-ideal conditions constituted by the fact that eidola have to traverse, not a void, but a space occupied by a physical stuff, viz. air. The eidola have to force their way through this relatively dense medium, and in so doing they drive a mass of air in front of them to the eye. But why should Democritus not have supposed that they disperse the intervening air, rather than compacting it? Here we have to speculate, since our sources are silent. He may have believed that the hypothesis of intervening air-masses gave the best explanation of the interference of the environment in vision, as evidenced, e.g., by the facts that the further away things are the less distinctly they are seen, and that they are seen less distinctly in fog than in clear air. A distant object arrives at the eye on the other side of a thicker mass of air than a nearer one; hence there are more air-atoms between the eye and the object in the former case, giving us a less distinct sight of the object. If this is correct, the function of the air-impressions is not to explain how visual perception occurs, but to explain why it is subject to the limitations which we observe.40 39 SeeBaldes57. 40 O'Brien 68 suggests that the function of the air-impressions is to account for the perception of the distance of the perceived object, as distinct from the perception of the

The Atomists -- Leucippus and Democritus  

MACEDONIA is GREECE and will always be GREECE- (if they are desperate to steal a name, Monkeydonkeys suits them just fine) ΦΕΚ,ΚΚΕ,ΚΝΕ,ΚΟΜΜ...

The Atomists -- Leucippus and Democritus  

MACEDONIA is GREECE and will always be GREECE- (if they are desperate to steal a name, Monkeydonkeys suits them just fine) ΦΕΚ,ΚΚΕ,ΚΝΕ,ΚΟΜΜ...

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