Also note that when you get this explanation and cause of, e.g., beauty--expressing that is going to be knowledge.
A worry: why think the cause of beauty is going to be the definition/explanation of beauty (as we might now think)?
Note that Plato might get out of this: if you find a cause that is a cause by virtue of being the nature of (explanation of), then it can fill both roles (i.e. cause and definition/explanation).
[Is a good way to think about this to say that he's got hold of something like Aristotelian formal cause here?]
Main character here a stranger from Elea, talking to Theaetetus the day after the Theaetetus (the dialogue). Brief meeting with Socrates. Eleatic stranger, obviously, representing Parmenidean school.
Question of defining a sophist--are they different from a) politicians b) philosophers?
Difference from other dialogues: Eleatic stranger makes definite doctrinal proposals.
The attempt at definition: method of collection and division:
- get a large class of things;
- divide into smaller things until get what you want;
- e.g. to define angling, start with hunting, subdivide (into two--not always named);
- at end, get list of classes, with one the definiendum.
The problem of non-being:
- Context: Proposed definition of Sophist is someone who sells falsehoods (images) for money;
- To get that as definition, want falsehoods to be real;
- The worry: The Sophist would deny there's any such thing as falsehood--to say what falsehood is involves using concept of non-being, but PPMI rules out concept of non-being, so looks like the definition of sophistry includes a meaningless term;
- How falsehood involves non-being: to say a falsehood is to say that what is not is, or what is, is not;
- Question then of what the problem with non-being is.
- First idea: states of affairs that don't obtain (e.g. on a nice day you could say "It's not raining"-- that would be true, but it would be true in virtue of a state of affairs not obtaining, i.e. it not raining;
- So we have a state of affairs "inherently" negative (not raining) being somehow real as one idea to explain non-being, but this seems odd since what's real just seems to be nothing to do with rain, so hard to see how anything negative is manifested (or 'real') at all;
- Second idea: when I say a falsehood (e.g. "It's raining" on a nice day) what's expressed is a state of affairs that doesn't obtain;
- So, again, second idea is that falsehoods involve these odd things--states of affairs that don't obtain;
- So there only seem to be "positive" states of affairs--things that do obtain.
- So what's the problem of non-being? That saying what a falsehood is entails mentioning something (a non-obtaining state of affairs); but if there aren't any such, then our definition of falsehood includes a term with no meaning [?]; and that makes it a bad definition.
- Another problem for Plato: the Forms explain, metaphysically, positive states of affairs (e.g. things are beautiful because they participate in Form of beauty). But what about negative states of affairs [e.g. not being beautiful = being ugly]? Do we now also need a Form of ugliness? Altnerative: might say that some things fail to participate in a Form. But how to explain this--what is it not to participate.
- Another way to think about this: the Forms came in to explain truth; now want explanation of falsehood (esp. since we have Sophists there is no falsehood).
- So want to explain falsehoods and negative predications by way of analyzing positive states of affairs;
- They consider "Theaetetus is flying", a falsehood.
- Proposal: Theaetetus is participating in some Forms, e.g. sitting. So "Theaetetus sits" is true, and we have an explanation of that. But Sitting, the Form, participates in another Form, Difference From All The Things That Are Flying [or Difference From Flying, The Form?] Since Theaetetus participates in that Form, "Theaetetus is flying" is false.
- Note: other interpretations of this.
- The work of negation done by the Form of Difference--when something participates in this (and note, seems to be only Forms that participate in this Form), get [possibility of] falsehoods.
- This new in the Sophist: idea that Forms participate in others.
- Idea of greatest kinds: Being, Sameness, Difference, Motion, Rest
- Is this a problem? We had things participating in Forms. Now Forms participating in Forms. But this might be a problem--e.g. Third Man problems. So why think that Forms can participate in each other?
- Note that one reading of this is whether properties can have properties, i.e. whether there are second order properties.
- Example: If the Form of Motion is not, numerically, the same Form as the Form of Rest, then the Form of Motion differs from the Form of Rest in one way. So the Form of Motion participates in the Form of Difference (w.r.t. the Form of Rest)--just like any physical object can participate in the Form of Difference (w.r.t. some other physical object).
- Note: he might not have to say that all Forms participate in all others--might be that all Forms share in some Forms, e.g. the greatest kinds all participate in Sameness, but no Forms share in Motion or Rest [that seems to make sense], all Forms share in Being. So maybe can tell an interesting story here. (Suggestion that figuring out inter-relations of Forms is the 'work' of philosophy.)