Single Idea 6768

[catalogued under 26. Natural Theory / B. Natural Kinds / 1. Natural Kinds]

Full Idea

If real essences are decided by microstructure, then what we call the element tin is not a natural kind, but a mixture of 21 different kinds, one for each isotope. There also exist two different allotropes of tin - white tin and grey tin.

Clarification

'Isotopes' vary in their numbers of neutrons; allotropes differ in their structure

Gist of Idea

Tin is not one natural kind, but appears to be 21, depending on isotope

Source

Alexander Bird (Philosophy of Science [1998], Ch.3)

Book Reference

Bird,Alexander: 'Philosophy of Science' [UCL Press 2000], p.107


A Reaction

This example vividly brings out the difficulties of the Kripke-Putnam view. If natural kinds 'overlap', then there would be a very extensive overlap among the 21 isotopes of tin.