Full Idea
It emerges that 'part', like other formal concepts, is not univocal, but has analogous meanings according to whether we talk of individuals, classes, or masses.
Clarification
'Univocal' means having only one meaning
Gist of Idea
A 'part' has different meanings for individuals, classes, and masses
Source
Peter Simons (Parts [1987], Intro)
Book Reference
Simons,Peter: 'Parts: a Study in Ontology' [OUP 1987], p.2
A Reaction
He suggests that unrestricted sums are appropriate for the last two, but not for individuals. There must be something univocal about the word - some awareness of a possible whole or larger entity to which the thing could belong.