Full Idea
A dispositional property is the classification of a property according to its functional role....[p.85] What is essential to a disposition - its identity condition - is its functional role.
Gist of Idea
Dispositions are classifications of properties by functional role
Source
Stephen Mumford (Dispositions [1998], 04.5)
Book Reference
Mumford,Stephen: 'Dispositions' [OUP 1998], p.75
A Reaction
This is Mumford's view of dispositions. I am wary of any proposal to define something according to its role, because it must have an intrinsic nature which equips it to have that role.