Full Idea
From the simple fact that '1' figures in the definition of '2', it does not follow that 1 is part of 2.
Gist of Idea
Figuring in the definition of a thing doesn't make it a part of that thing
Source
Gideon Rosen (Metaphysical Dependence [2010], 10)
Book Reference
'Modality', ed/tr. Hale,B/Hoffman,A [OUP 2010], p.125
A Reaction
He observes that quite independent things can be mentioned on the two sides of a definition, with no parthood relation. You begin to wonder what a definition really is. A causal chain?