more from this thinker     |     more from this text


Single Idea 14266

[filed under theme 2. Reason / D. Definition / 5. Genus and Differentia ]

Full Idea

For us, sets constitute the most natural example of a hierarchical structure within the abstract realm. But for Aristotle it would have been definitions, via their natural division into genus and differentia.

Gist of Idea

Aristotle sees hierarchies in definitions using genus and differentia (as we see them in sets)

Source

Kit Fine (Aristotle on Matter [1992], 1 n4)

Book Ref

-: 'Mind' [-], p.37


A Reaction

Genus and differentia are only part of the story in Aristotle, and this remarks strikes me as perceptive. It is precisely the mapping of the explanatory hierarchy which Aristotle seeks in a good definition.


The 23 ideas with the same theme [its class, and then its distinguishing feature]:

'Plane' is the genus of plane figures, and 'solid' of solids, with differentiae picking out types of corner [Aristotle]
Whiteness can only belong to man because an individual like Callias happens to be white [Aristotle]
A definition is of the universal and of the kind [Aristotle]
Definition by division is into genus and differentiae [Aristotle]
If the genus is just its constitutive forms (or matter), then the definition is the account of the differentiae [Aristotle]
If I define you, I have to use terms which are all true of other things too [Aristotle]
Aristotle's definitions are not unique, but apply to a range of individuals [Aristotle, by Witt]
Species and genera are largely irrelevant in 'Metaphysics' [Aristotle, by Wedin]
Differentia are generic, and belong with genus [Aristotle]
'Genus' is part of the essence shared among several things [Aristotle]
We describe the essence of a particular thing by means of its differentiae [Aristotle]
The differentia indicate the qualities, but not the essence [Aristotle]
In definitions the first term to be assigned ought to be the genus [Aristotle]
The genera and the differentiae are part of the essence [Aristotle]
Aristotelian definition involves first stating the genus, then the differentia of the thing [Aristotle, by Urmson]
If definitions must be general, and general terms can't individuate, then Socrates can't be defined [Aquinas, by Cover/O'Leary-Hawthorne]
The definitions expressing identity are used to sort things [Aquinas]
Definition is resolution of names into successive genera, and finally the difference [Hobbes]
Genus is a partial conception of species, and species a partial idea of individuals [Locke]
Genus and differentia might be swapped, and 'rational animal' become 'animable rational' [Leibniz]
Aristotle sees hierarchies in definitions using genus and differentia (as we see them in sets) [Fine,K]
Definition distinguishes one kind from another, and individuation picks out members of the kind [Oderberg]
'Animal' is a genus and 'rational' is a specific difference [Oderberg]