Single Idea 1553

[catalogued under 6. Mathematics / A. Nature of Mathematics / 2. Geometry]

Full Idea

No perceptible object is geometrically straight or curved; after all, a circle does not touch a ruler at a point, as Protagoras used to say, in arguing against the geometers.

Gist of Idea

No perceptible object is truly straight or curved

Source

Protagoras (fragments/reports [c.441 BCE], B07), quoted by Aristotle - Metaphysics 998a1

Book Reference

'The First Philosophers', ed/tr. Waterfield,Robin [OUP 2000], p.220