CLAS 161/PHIL 108

Mi-Kyoung Lee, 'The Theaetetus' in Oxford Handbook to Plato

• Structure of the Dialogue: very briefly (to be expanded in notes that follow: this is a high-flying survey of the whole dialogue: do not expect details at each stage: some of it is left puzzling)
  
• Initial banter: Soc., Theodorus, and Theaetetus are introduced by Eucleides, who is talking to Terpsion
• Preliminary definition of Knowledge and midwife episode: first definition is very similar to Euthyphro's first definition of piety, and the midwife episode is one of the most famous in Plato.
• First Definition of Knowledge (K1): Knowledge is perception 151e
  
• "Secret Doctrine" is introduced to support K1
• rejected at 181-183
• K1 itself rejected 184-186
  
• Second Definition of Knowledge (K2): Knowledge is True Opinion 187b
  
• Attempts to explain false belief fail: casts doubt on K2
  
• K2 also directly refuted by examples of cases where true belief is not knowledge 200d-201c
  
• Third Definition of Knowledge (K3): Knowledge is True Belief with an Account (a logos) 201c
  
• "Dream Theory" introduced, including various metaphysical assumptions 201d-203c
  
• Asymmetry of Knowledge
  
• Things for which there is an account can be known: things for which there is no account cannot 201d-203c
  
• Rejected 203e-205e
  
• Attempts to elucidate what an account is fail 206c-210a
• Theaetetus ends in aporia.

• Epistemology and Metaphysics
• In the Republic, epistemology is linked closely to metaphysics: according to the central books of the Republic, knowledge is impossible without the forms.
• The Theaetetus too assumes a close link between epistemology and metaphysics, but it has no mention of and barely even hints about the Forms.
• Tht. brings in metaphysics as part of the assumptions needed to try to make each of the three definitions of knowledge offered in the dialogue work.
• The objects of knowledge in the Tht. are ordinary, often but not always sensibles: people, things, etc. Not Forms.
• In the Republic too, it seems there may be knowledge of ordinary sensible things, but only via the Forms, which are the paradigmatic objects of knowledge.
• Theaetetus and Forms
• Different positions possible
• Theaetetus is post-Forms. Plato has renounced the Forms.
• Plato is clearing the way for Forms.
• At least some of the problems raised during the Tht. would be solved by Forms. Ask yourselves which ones would, and which might not, be solved by Forms.
  
• Plato is simply considering whether various theories of knowledge that don't involve Forms can work and wants to avoid assuming the Forms as part of his examination of those other theories. An implicit "dialectical requirement" to give alternative theories a fair shake.
• What about the various positions in the Tht, which are incompatible with Forms?
• They may be simply part of the dialectic: Plato is not necessarily endorsing them, just examining them or using them.

The three definitions

• K1: Knowledge is Perception
• our senses are accurate and informative about their proper objects
• proper objects are the things that each sense can sense: sight can sense color and shape; touch can sense temperature and texture; etc.
• knowledge depends on and builds from perception
• In order to support K1, Socrates bring in the Protagorean Measure Doctrine
• "Humanity is the measure of all things, of the things that are that they are, of the things that are not, that they are not."
• The Measure Doctrine, simply put: Whatever Appears to be the case to one is the case for one.
• Plausible because senses are a criterion of truth (at least in some cases)
• So senses are of what is and are free from falsehood (152c)
• Inference that perception is the same as knowledge
• This is a version of Empiricism: "Since perception is infallible with respect to the sensible qualities, it should be regarded as a kind of knowledge"
• K1 generalizes this to all knowledge: nothing exists that is not perceived.
• But at this point, 'perception' seems to be exceeding pure sense perception.
• Heraclitean theses also introduced as the 'Secret Doctrine.'
• "Everything is in motion and changing."
• "If something is F, then it also is or will be its opposite, not-F" (152de)
• Explanation of what Perception is: Perception is an interaction and is unique on each occasion it occurs
• There are two offspring of each act of perception: perceptible properties and perceivings.
• Why can't one occur without the other? It's just assumed to be the case.
• How should we interpret the measure Doctrine?
1. Relativism about truth? (truth is relative: there is no absolute truth, about anything: it all depends on vantage point and context)
2. Infallibilism (all beliefs/appearances are true, period, in a non-relative way)
3. "relativism of fact" (whatever appears to be true for one is true for one)
• 3 doesn't say whether truth itself is relative, but is relativist in a different way
• How are the Measure Doctrine, the Heraclitean Theses and K1 related?
1. Mutual entailment: each requires each
• Plato is identifying logical consequences of K1 and what is sufficient for K1
  
2. Heraclitean Theses are sufficient for the Measure Doctrine, which is sufficient for K1
• Plato is exploring what a K1 world might be like
• How do these possibilities combine?
• A creates a problem with 1: relativism about truth does not commit one to flux, rather it is incompatible with it (if flux is true in a non-relative way)
• What about A with 2: all perceptions/beliefs are true (in a non-relative way): that implies that contradictory states are simultaneously true, which could explain why Plato introduced the Heraclitean flux
• B simply says that K1 turns out to be true with certain metaphysical assumptions.
• If we assume Heraclitean Flux, then the Measure Doctrine and K1 turn out to be true
• It all falls apart, however, because flux means that not only are the objects of knowledge changing, but so is knowledge, perception, perceptible properties, etc.: everything is changing. The flux has no inner logic that identifies a limit to flux.
• Perceptions cannot be true unless there is some sort of stability: there is nothing for them to be true about.
• K1 and the Measure Doctrine can be true, but only in a world in which there are limits to flux.
• Preparation for the Forms? Could the Forms solve these problems?
  
• What about K1 itself?
• Perception is infallible about the proper sense objects
• BUT it cannot get beyond them: it cannot form judgements about being, what things are.
• The idea seems to be that perception has no propositional content, no way to form a judgement about anything beyond the proper object of each sense.
• Different ways to read this: maybe perception includes some minimal judgement capacity, but cannot get to things like "advantageousness," "value," "beauty," etc. or maybe it doesn't even have minimal judgement capacity.
• Sight says "There is a red circle." Taste says "This is salty."
• But we might still be able to know things about the objects of perception (if we have other means to get at their being)

•  Knowledge as True Belief (K2)
• If K1 failed because perception cannot form judgements and get at being, what about judgements themselves? Don't they "get at being"? Why can't true beliefs be knowledge?
• Problem with this is that having a true belief is not the same as having a reliable capacity to form true beliefs: one might have a true belief by accident or for the wrong reasons, or one might have/form a true belief but not be able to tell it from the other, false beliefs one holds too, etc.
  
• Plato seems to assume that someone who knows something cannot make mistakes about it, and so any candidate for knowledge must not be capable of making mistakes about the object of knowledge.
• And so, Plato's first tack is to try to figure out how false judgement is possible
• WHY? What does that have to do with true judgement?
• They try five times and fail each time (188-200)
• They cannot figure out how one can be thinking about X and make a mistake about it.
• To have true belief about X, you must be thinking about X (not something else), which involves judging it truly, and so by K2 you know it. If you know it, you cannot be mistaken about it, since you cannot know and not know the same thing, and so it seems impossible to think about X and be mistaken about it simultaneously.
• I.e. thinking about something involves knowing it. It's impossible to be mistaken about it.
• The famous Wax Block model
• allows for mistakes: it allows for one to think about or perceive Fido but not as Fido: you think about Fido without thinking about what Fido is, somehow. 195b-196c
  
• This apparently works for perception, but Socrates rejects it because it does not work for non-perceptual cases like 2+2=5.
• This whole discussion involves identity statements (judging that X is X or that Y is Y): is that a problem? There are, after all, other cases of opinion, aren't there?
• Plato also examines K2 directly, not just via false judgement:
• A jury may be convinced that X is the case, but fall short of knowledge: they don't have the proper link between X being the case and knowing it (only the eyewitness does, it is said: moderns know better, right?). They have correct judgement, not knowledge.
  

• Knowledge is True Belief with an Account (a logos) K3
• In a way, K2 is the equivalent of K3, if having an account is "having the distinguishing mark that sets off what one knows from everything else"
• ***********
  
• Lee suggests that if the objects of knowledge are kinds instead of particulars, some problems disappear. (more later at end of page)
  
• So, do we know particulars or kinds? Remember this question: it is important at the end of this page!
  
• ************
• K3 suggests that having a true opinion about X is insufficient for knowledge of X if one's opinion is not backed up by the proper link between X's being the case and one's opinion. One might believe one's true opinion for false reasons, for instance.
  
• K3 is the account of knowledge which Plato apparently favors in the Meno, which is a mark in its favor.
• Asymmetry of Knowability: a thing must have an account to be knowable. If it does not it is not knowable.
• The Dream Theory:
• It is a dream that shows how K3 could be true.
• What does it mean that it is a "dream"?
  
• Things are of two kinds: elements and things composed out of them.
• Elements can only be named, not known.
• You can't even say that an element "is" or "is one" or refer to it with "each" "that" or "itself"
• so an element has no being? maybe only basic being? proto-being? no unity? self-identity? Try to remember this when we read the Parmenides, and the Sophist: also, think about what forms are: could they be these things? No: they have an account, right?
  
• Saying that an element 'is' or 'is one' or 'different from ...' would be adding something to the element and so making it composite
• Elements are perceived (how?)
  
• But you can build an account out of names of elements and their relations, and so, if knowledge is true belief with an account, things composed of elements can be known 201e-202b
• What an element is is left vague
• are they material?
• are they meanings?
• Plato is apparently not ready/willing/interested in exploring that here.
• The elements are, however, ontologically basic, and the things composed out of them are "epistemologically" basic, it seems.
• What about Fine's coherentism? Is this compatible with that?
  
• The accounts built out of names of elements are all identity statements, says Lee. They are all statements or definitions of what a thing is. "All judgements are judgements of identity about particular objects." P 425
• Enumeration of Elements: Knowable things are no more than their parts and are analyzable into their parts.
• Plato refutes the Dream Theory in two ways:
1. Assuming that the whole is the sum of its parts
• Plato argues that the asymmetry of knowability between elements and complexes of elements is wrong: they are either equally knowable or equally unknowable 203d-205e
  
2. Assuming that the whole is something other than the sum of its parts
•  Notices that our actual experience says that we come to know the elements more fundamentally than their complexes: example is letters in written words. We learn the letters first, then the written words. (OK, so he needs a course in neuroscience and linguistics: could we save his account even after taking those courses?)
• Plato's aim must be to show that whether one assumes that a thing is the sum of its parts or not, asymmetry of knowledge is wrong.
• If we reject the asymmetry, then elements and complexes are either equally knowable or equally unknowable
• Surely Plato wants us to conclude that they are equally knowable.
• What about K3: that knowledge requires an account? How should we react to it?
  
• reject the requirement of an account? not everything needs an account to be known
• some things, such as elements at least, can be known in other ways than via an account
  
• retain it and reject the asymmetry of knowledge as well as the idea that elements don't have accounts?
• To do so, we need to reject the idea that an account is an enumeration of elements, because elements themselves don't have elements if they are really "elemental", and so there can be no account of an element itself.
  
• Perhaps one can give an account in terms of classifying the elements instead of identifying and enumerating their parts: say how they fit in relation to each other, as one does in explaining the letter S.
• We need to get clearer on what an "account" (logos) is:
• Plato tries out three candidates and rejects them all, for different reasons (206-210)
  
• An account might simply be speech: that's ridiculous, for the act of saying something or having a word for something does not make it any more or less knowable in terms of an account of knowledge, does it?
• An account is an enumeration of elements
• A wagon is "axle, wheels, bed, yoke, etc."
• Plato says that the dreamer of the dream theory would say rather that a wagon is the 100 individual timbers out of which it is made (as opposed to the kinds of timbers?).
• Obviously insufficient:
• no mention made of the relation of the elements, or their order, structure, etc.
• for instance, the 'same elements' could be used to make a table, perhaps? So the arrangement and even the process of construction could be needed.
• Plato means something different, however:
  
• He means that one must be able to recognize the elements of something even when they occur elsewhere in order to have knowledge.
• A kindergartner who knows her alphabet can spell some words right, but not all and cannot accurately predict and manipulate the elements of the words she spells right, so she doesn't really know how to spell yet.
• One must grasp the kind of thing each element is.
• An account is being able to state the identifying mark by which the thing one knows differs from everything else.
• Even correct judgement (K2) requires this, but that failed to be knowledge...
• Lee suggests that the objection holds only if one is thinking of individual particulars as objects of knowledge and that it does not hold if one is thinking of kinds of things as the proper object of knowledge.