Full Idea
Regularities exist because we classify kinds on the basis of their dispositions, not on pre-established divisions of kinds. The dispositions are the basis for the division into kinds, which is why all electrons behave in the same way.
Gist of Idea
Natural kinds, such as electrons, all behave the same way because we divide them by dispositions
Source
Stephen Mumford (Dispositions [1998], 10.7)
Book Reference
Mumford,Stephen: 'Dispositions' [OUP 1998], p.235
A Reaction
This strikes me as being so obvious that it is hardly worth saying, and yet an enormous number of philosophers seem to have been led up the garden path by the notion of a 'kind', probably under the influence of Kripke, Putnam and Wiggins.