Sophist (dialogue) - Method of Definition

Method of Definition

For more details on this topic, see diairesis.

The Eleatic Stranger pursues a different method of definition than features in Plato's other dialogues by the use of a model, comparison of the model with the target kind, division (diairesis), collection, and deduction from the collected kinds. At first he starts with the use of a mundane model (a fisherman), which shares some qualities in common with the target kind (the sophist). This common quality is the certain expertise (techne) in one subject. Then through the method of collection of different kinds (farming, caring for mortal bodies, for things that are put together or fabricated and imitation), he tries to bring them together (deduction) into one kind, which he calls productive art. The same is true with the collection of learning, recognition, commerce, combat and hunting, which can be deduced into the kind of acquisitive art.

After these two collections, he proceeds to the division of the types of expertise into production and acquisition, and then he tries to find out to which of these two sub-kinds the fisherman belongs (classification), in this case, the acquisitive kind of expertise. By following the same method, namely, deduction through collection, he divides the acquisitive art into possession taking and exchanging goods, to which sophistry belongs. The sophist is a kind of merchant. After many successive collections and divisions he finally arrives at the definition of the model (fisherman). Throughout this process the Eleatic Stranger classifies many kinds of activities (hunting, aquatic-hunting, fishing, strike-hunting).

After the verbal explanation of the model (definition), he tries to find out what the model and the target kind share in common (sameness) and what differentiates them (difference). Through this comparison, and after having been aware of the different kinds and sub-kinds, he can classify sophistry also among the other branches of the ‘tree’ of division of expertise as follows: "1. production, hunting by persuasion and money-earning, 2.acquisition, soul wholesaling, 3. soul retailing, retailing things that others make, 4. soul retailing, retailing things that he makes himself, 5. possession taking, competition, money-making expertise in debating."

Throughout the process of comparison of the deduced kinds through his method of collection, the Eleatic Stranger discovers some attributes in relation to which the kinds can be divided (difference in relation to something). These are similar to the Categories of Aristotle, so to say: quantity, quality, relation, location, time, position, end etc.

After having failed to define sophistry, the Stranger attempts a final deduction through the collection of the five definitions of sophistry. Since these five definitions share in common one quality (sameness), which is the imitation, he finally qualifies sophistry as imitation art. Following the division of the imitation art in copy-making and appearance-making, he discovers that sophistry falls under the appearance-making art, namely the Sophist imitates the wise man.

The sophist is presented negatively, but he can be said to be someone who merely pretends to have knowledge or to be a purveyor of false knowledge only if right opinion and false opinion can be distinguished. It seems impossible to say that the sophist presents things that are not as though they were, or passes off "non-being" as "being," since this would suggest that non-being exists, or that non-existence exists. Otherwise, the sophist couldn't "do" anything with it. The Stranger suggests that it is Parmenides' doctrine of being and non-being that is at the root of this problem, and so proceeds to criticize Parmenides' ideas, namely that "it is impossible that things that are not are."