Full Idea
I consider some apparent quantification over sets or classes of whatnots to carry genuine ontological commitment to 'sets' of them, but sometimes it is innocent plural quantification committed only to whatnots, for which I use 'class'.
Gist of Idea
Quantification sometimes commits to 'sets', but sometimes just to pluralities (or 'classes')
Source
David Lewis (On the Plurality of Worlds [1986], 1.5 n37)
Book Reference
Lewis,David: 'On the Plurality of Worlds' [Blackwell 2001], p.51
A Reaction
How do you tell whether you are committed to a set or not? Can I claim an innocent plurality each time, while you accuse me of a guilty set? Can I firmly commit to a set, to be told that I can never manage more than a plurality?