“…The tilting of the celestial axis was a problem that bothered several Presocratics. Since ancient times, its interpretation is haunted by the failure to recognize the difference between how things are seen from a flat and from a spherical Earth, as I have explained extensively elsewhere [Couprie 2009]. Hahn, too, falls into this trap when he mentions 'the stunning reality' for the archaic Greeks who thought that the Earth was flat, 'that either the cosmos is inclined 23.5 • north or that the Earth is inclined 23.5 • north' [176].…”