[there are] two kinds of things the nature of which it would be quite wonderful to grasp by means of a systematic art...the first consists in seeing together things that are scattered about everywhere and collecting them into one kind, so that by defining each thing we can make clear the subject of any instruction we wish to give...[the second], in turn, is to be able to cut up each kind according to its species along its natural joints, and to try not to splinter any part, as a bad butcher might do...phaedrus, i myself am a lover of these divisions and collections, so that i may be able to think and to speak.
Plato