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2. Reason / D. Definition / 5. Genus and Differentia

[its class, and then its distinguishing feature]

23 ideas
'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]