Full Idea
The properties of material things with which the sciences deal are not the qualities we observe them to have, but the dispositions of those things to engender the states and qualities we observe.
Gist of Idea
Scientific properties are not observed qualities, but the dispositions which create them
Source
Rom Harré (Laws of Nature [1993], 2)
Book Reference
Harré,Rom: 'Laws of Nature' [Duckworth 1993], p.44
A Reaction
I take this to be the correct use of the word 'qualities', so that properties are not qualities (in the way Heil would like).