Mencius - Book 6, Part 1, Chapter 3

The philosopher Kâo said, 'Life is what we call nature!'

Mencius asked him, 'Do you say that by nature you mean life, just as you say that white is white?' 'Yes, I do,' was the reply. Mencius added, 'Is the whiteness of a white feather like that of white snow, and the whiteness of white snow like that of white jade?' Kâo again said 'Yes.'

'Very well,' pursued Mencius. 'Is the nature of a dog like the nature of an ox, and the nature of an ox like the nature of a man?'

~ James Legge translation via nothingistic.org ~

 Go here to read the introductory post to this serialized version of the Works of Mencius.