Single Idea 13575

[catalogued under 26. Natural Theory / B. Natural Kinds / 7. Critique of Kinds]

Full Idea

There cannot be any borderline cases between the real essences of different natural kinds because, if there were, the distinctions between the kinds would be superficial, like the blue/green distinction.

Gist of Idea

If there are borderline cases between natural kinds, that makes them superficial

Source

Brian Ellis (Scientific Essentialism [2001], 1.05)

Book Reference

Ellis,Brian: 'Scientific Essentialism' [CUP 2007], p.31


A Reaction

His particular target here is biological natural kinds, in which he doesn't believe, because they blur across time, in the evolutionary process. Personally I am inclined to relax the notion of a natural kind, otherwise they are too basic to explain.

Related Ideas

Idea 16750 If there are just arrangements of corpuscles, where are the boundaries between substances? [Pasnau]

Idea 17410 Moseley showed the elements progress in units, and thereby clearly identified the gaps [Scerri]