Download 8. Handout on Plato`s Theory of Forms - Elly Pirocacos

Dr. Elly Pirocacos
The Philosophy of Plato
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HANDOUT ON PLATO’S THEORY OF FORMS
Plato is most famous for his Theory of Forms (or Ideas). This is an epistemological
theory—namely it is a theory of knowledge.
It is best to see Plato as responding to problems of knowledge raised by cosmological
and epistemological theories of his two most influential predecessors: HERACLITUS
and PARMENIDES (the Pythagorians were also a great influence on Plato but their
influence is not as directly pertinent to this discussion). Heraclitus is clearly alluded to
in Plato’s Phaedo, Cratylus, and Theaetetus. Parmenides has an entire dialogue
named after him, and is most memorably alluded to in Plato’s Sophist where the topic
of falsehood and knowledge is underway and clearly entangled in Plato’s later
metaphysics.
I. HERACLITUS (the following fragment is taken from Plato’s Cratylus) says
“everything is in a constant state of flux”—τα πάντα ρεί—(there are moderate and
extreme views of this doctrine). This posed an important question for Plato, “if
everything is constantly undergoing some sort of change, what is it with regards to any
given thing that makes it what it essentially is so that it can be correctly identified as
the thing named?” Why is this problematic? Consider, if things (the objects of
knowledge) in this world are undergoing change, this implies that under different
circumstances (at varying times) the same thing may be described by differing, indeed
contrary (sometimes contradictory) attributes. This may introduce interesting
epistemological paradoxes.
For instance, stick1 (3 cm) is described as long when laying beside another stick2
which is only 1cm; and yet, laying beside stick3, which is 20 cm, it is described as
short. Hence, stick1 is both short and long; (though there is some confusion in Plato’s
discussion of whether these terms are contraries or contradictories); but shortness and
longness are contraries; that is, longness is not-shortness and vice versa; but from this
it follows that the same thing, namely stick1, is and is not short at the same time. But
this is a straight contradiction (Phaedo 74, Republic 479 and even the later dialogue
Timaeus 49-50)).
What does this suggest? It shows us that the very same object stick1 can present
contrary appearances. So when on one occasion the object appeared to be large (say
when you are right up against it) and on another occasion the same object appeared to
be tiny (say from the heights of the Empire State Building), it would not be at all
strange to ask, will the real stick1 please stand up. In other words, is this object really
large or tiny?
Plato’s metaphysical view will actually confine the Heraclitean doctrine of flux to
what is called the World of Appearance which we (man) participate in through senseperception and from which beliefs or opinions (doxa) are derived but not knowledge.
Indeed, this metaphysical doctrine will be a consequent of his epistemological
position.
Dr. Elly Pirocacos
The Philosophy of Plato
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II. From an epistemological point of view Plato, siding with PARMENIDES, will hold
that “knowledge is of what is” and “knowledge (unlike mere belief) is infallible”.
These two premises are basic to Plato’s epistemological theory, so remember them.
Parmenides was struck by the problem of being able to think truthfully which required
that thought attend upon “what is”. “What is” turns out to be thought that not only
does not involve contradiction but which is essentially of that given thing. The view
must have been twofold: on the one hand when thinking of something in terms of
something else, it is like you betray what that thing actually is and second, when
thought attends upon one thing in terms of another thing, thought is actually
entertaining that thing in terms of “what is not”; indeed, in terms of what it is not.
This involves a straight contradiction and must be rejected as false.
For Parmenides it turns out that to think of something only and essentially in terms of
what it is, and never in terms of what it is not, can only come about when the object is
simple, perfect, indivisible, ungenerated, homogenous, and unchanging (fr. 8.2-3).
Indeed, if this is so, thought can not be complex since even the simplest form of
complexity involves qualification. When you qualify the subject of thought you are
talking about it under a particular guise (as green, as large even though the object
itself is not what greenness is or largeness is) which requires employing terms that
take you beyond the subject term. So, for instance, in the sentence, “Homer is tall” (or
x is F) Homer is identified by thought as ‘Homer’ and is tall is also identified by
thought as ‘tallness’. In both instances the requirement is not a strange one: what else
does it mean to think successfully or truthfully of a given thing than to think of it as
itself? From this innocuous sounding premise however, a rather peculiar consequent
follows: Homer and tallness are two independent entities, so that when the sentence
“Homer is tall” is thought/uttered, a contradiction ensues because Homertallness,
such that the sentence implies the thought “Homer is not-Homer” because the
sentence “Homer is tall” involves thinking of ‘Homer as tallness’, that is, as
something that Homer is not. The problem that seems to be plaguing Parmenides’
understanding of this predicative sentence is the problem of how to relate parts to
wholes or properties to their objects without at the same time betraying what the thing
in question really is.
As a result of the above, Parmenides’ thought is left barren with nothing to think
about. All complex thought is rendered impossible. The only thing that can be thought
is εστί (being). This is, of course, not much of a thought. That is, it does not convey
anything.
III. PLATO’S THEORY OF FORMS has been described as Plato’s attempt to deal with a
number of different problems. For this variation Plato is partly to blame as he puts his
Forms to work to perform different functions (indeed some argue that these functions
correspond to different periods of Plato’s philosophical development):
1) as objects that correspond to SOCRATIC DEFINITIONS (remember Socrates was a
moralist and as such was concerned to define moral concepts, like justice
(Republic), piety (Euthyphro), virtue (Meno) and so on. As such, a definition
would be correct just in case that it successfully or accurately described the Form
Justice, Piety, Virtue.
Dr. Elly Pirocacos
The Philosophy of Plato
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2) the objects of RECOLLECTION (to understand this one must recall that for Plato our
knowledge of definitions corresponding to Forms is acquired a priori, which
means prior to and independently from experience. If not via experience,
wherefrom? Well from recollection of our “acquaintance” with Forms in our
“time” before our physical existence. These Forms then, are the entities that our a
priori truths are about.
3) Forms are the entities to which the objects of our sensory experience correspond.
Sensory objects themselves are only IMPERFECTLY black or equal and so on, since
under different circumstances they appear more or less black or equal (sensible
objects or the objects of sensory experience fall short of these characterizations).
Reconsider the example with the sticks. We make judgments about the sticks, say
that this stick is large or equal to another stick even though we have never actually
experienced such things as Largeness and Equality in perception. Forms are then
the entities that perfectly embody these characteristics we have in mind.
4) Forms are also the objects of KNOWLEDGE. There is a class of things that are
stable, permanent, and changing and these are the things that knowledge is about.
Their copies in the physical world are imperfect and themselves can only give rise
to beliefs.
5) Finally there is the famous ONE OVER MANY argument which implies that Forms
also play a semantic role. That is, Forms are the universal meanings of names that
we are talking about when we say things like, “Justice is F” such that this
statement can be judged as true or false. There is, therefore, one Form for each set
of many things that are called by the same name.
Despite these varying functions, Plato’s Forms are what we call REAL—that is, they
actually exist in their own right. REALISM is the name of the theory that this position
endorses—namely that (in this case) the Forms are entities that exist independently of
anyone thinking them (i.e. they are mind independent entities). REALISM is contrasted
with another general metaphysical view, IDEALISM, which claims that the world and its
contents are mind-dependent.
In response to Heraclitus, Plato must have found it difficult to disagree with the
doctrine of flux given the abundance of examples that sensory experience provides. So
Plato agreed with Heraclitus that the world of sensory experience is in a constant state
of flux. Still, he could not agree that knowledge could have the varying character that
sensory experiences have. (i) Knowledge must be constant or universal. That is,
whatever is to count as knowledge must be the same for all similar things irrespective
of circumstance or person. The point is that, whether Socrates asked “what is virtue”
in ancient Greece, or a college student in contemporary USA, the answer should
always be the same. Plato supposed that this world can not be the whole story; there
must be more than meets the ‘eye’. Since this world has the character of flux, it must
somehow be responsible for the kinds of “ideas” that we come to have. Indeed, if our
ideas were wholly caused by the objects of sensory experience we could not hope to
ever uncover knowledge.
Since Plato would not accept the impossibility of knowledge, he supposed that there
must be different kinds of things that we can somehow be acquainted with that do
render knowledge. Notice that fault is found not with sensory experience or the way in
which we process the experiences that we come to have of the world of sensory
Dr. Elly Pirocacos
The Philosophy of Plato
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objects, but with the objects themselves. Since these objects (perhaps because they are
subject to different laws) are imperfect (constantly altering in appearance and never
quite black, equal and so on), and knowledge is possible, it follows that there must be
other kinds of objects that give rise to knowledge. These objects are Plato’s Forms.
The world of sensory objects, as indicated above, is called the World of Appearance,
and the world of Forms is called the World of Ideas/Forms.
In response to Parmenides, Plato must have found it difficult to disagree that (ii)
knowledge is of what is (especially in the Parmenides and the Sophist) and that
knowledge is derived not by sensory experience—empirically, but rather (iii)
knowledge is derived from reason/thought (though perhaps he agrees, Parmenides
may not have been his inspiration for this point). The first point we have already seen
in the discussion of Parmenides. Parmenides held that to think of something truthfully
or successfully means to think of that thing as itself. This was the outcome of a long
syllogistic argument found in surviving fragments of Parmenides. The argument
begins with what is possible for thought to think: “what is”, “what is not”, and “what
is and what is not”. Only “what is” can be thought truthfully (“what is not” is
altogether impossible because “what is not” is not there to be identified for thought to
be of; and “what is and what is not” involves contradiction) because only in this case
is the object of thought not betrayed by qualification. We can exploit this idea of
qualification to make Plato’s Theory of Forms more clear. A Form, unlike, its
corresponding sensible is what it is without qualification. That is, (a) a Form need not
be described in terms of something else whereas sensible objects can not be described
except in reference to something else. Note that a sensible object can be described in
reference to another sensible object. E.g. stick1 is equal in reference to certain
circumstances and these certain other sticks. A sensible object may also be described
in reference to a Form (x is F)—this sounds more in keeping with Plato. Eg.2 the
statement, “this stick is Equal”, contains the term Equal which is a Form; Eg.3 “the
thing which is Equal” again contains a reference to a Form (it can not be truthfully
called Equal unless it can be recognised as participating in the Equal).
Notice that what has been advocated thus far is riding on the basic premises
“knowledge is infallible” whereas “belief is fallible” and “knowledge is of what is”
whereas “belief is of what is and is not”. These premises in turn lead to the two world
view—the World of Appearance (WOA) and the World of Ideas (WOI)—and to two
distinct routes of human contact with these world. The WOA is accessed via sensory
experience whereas the WOI is accessed via thought/reason. Sensibles are then
described accurately as such and such only because through sensory perception do we
come into contact with vague images of the entities which they represent and which
we had wholly and completely perceived in our “time” before our physical existence.
We now come to recall (The Theory of Recollection) these entities/Forms.
THE GENERAL FORM OF THE ARGUMENT THAT PLATO ENDORSES IS AS FOLLOWS (REP. V
476-480):
1.
2.
3.
4.
Knowledge is possible.
Knowledge is of what is.
Knowledge is infallible, belief is fallible.
Therefore, what is known must be, what is believed may not be.
Dr. Elly Pirocacos
The Philosophy of Plato
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5. That is, what is known must be something that “purely and absolutely is”, what is
believed is something that “partakes in both being and not-being”.
6. Therefore, there are things that purely and absolutely are—things we call Forms
(the F itself). The participants in the Forms (the many F’s) both are and are not.
7. That is, Forms are the objects of knowledge; their participants are the objects of
belief.