I like this geometric juxtaposition, though I might have made the distinction sharper: as distinct as circle and square?  As distinct as line and circle?

‘Distinct as polygon and square.’

Source: Christopher Logue, War Music: An account of Books 1-4 and 16-19 of Homer’s Iliad, London: Faber and Faber, 2001, p. 198

Photo credit: pixabay.com – Artturi_Mantysaari