A Critique of Ostension

Sextus M 7 267-8 ‘The Epicureans thought that the conception of the human being could be presented ostensively, saying ‘a human being is a shape like this, along with the possession of soul.’ But they did not realise that if the thing being shown is a human being, the thing not being shown is not a human being. And again, a showing of this kind is carried out either with a man or a woman, either with an old person or a young one, with someone snub-nosed or hook-nosed, straight-haired or curly-haired, and so on with other differences. And if it is carried out with a man, woman will not be a human being, while if with a woman, the male will be excluded, and if with a youth, other ages will be deprived of humanity.’

(trans. R. Bett, Against the Logicians, CUP 2005).

Augustine also has (what is usually interpreted as) one in De Magistro; anyone know of any others in antiquity?