Full Idea
To establish a definition through division, you must aim for three things: you must take what is predicated in what the thing is; you must order these items as first or second; and you must ensure that these are all there are.
Gist of Idea
Definition by division needs predicates, which are well ordered and thorough
Source
Aristotle (Posterior Analytics [c.327 BCE], 97a23)
Book Reference
Aristotle: 'Posterior Analytics (2nd ed)', ed/tr. Barnes,Jonathan [OUP 1993], p.66
A Reaction
This gives an indication of the thoroughness that Aristotle expects from a definition. They aren't like dictionary definitions of words. He expects definitions to often be very lengthy (see Idea 12292).
Related Idea
Idea 12292 Definitions are easily destroyed, since they can contain very many assertions [Aristotle]