Full Idea
When a group of objects have the similarity we are inclined to attribute to possession of a common quality, the membership of the group will serve all the purposes of the supposed common quality ...which need not be assumed to exist.
Gist of Idea
When we attribute a common quality to a group, we can forget the quality and just talk of the group
Source
Bertrand Russell (Our Knowledge of the External World [1914], 2)
Book Reference
Russell,Bertrand: 'Our Knowledge of the External World' [Routledge 1993], p.51
A Reaction
This is the earliest account I have found of properties being treated as sets of objects. It more or less coincides with the invention of set theory. I am reminded of Idea 9208. What is the bazzing property? It's what those three things have in common.
Related Idea
Idea 9208 Philosophers with a new concept are like children with a new toy [Fine,K]