ANCIENT PHILOSOPHY
PLATO – FORMS AND RECOLLECTION
LECTURE
PROFESSOR JULIE YOO
The Theory of Forms
Forms and Definitions
Forms and The Identity of Objects
The Problem of the One Over the Many
Motivating the Problem
Types and Tokens
Universals and Particulars
The Theory of Recollection
Why Forms Can’t Be Perceived Through the Senses
Learning is Recollection: The Slave Boy Does Geometry
Modern Nativism and the Recollection Argument
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PLATO AND THE THEORY OF FORMS
To understand Socrates’s position better, we need to delve into one of Plato’s most enduring
theories to have influenced Western philosophy. That is his Theory of Forms, presented through
the character of Socrates.
Forms and Definitions
In many of Plato’s dialogues, the important question that Plato/Socrates wants to answer is:
“What is the definition of X?” For Plato a proper definition identifies that which is common to
all the various differing instances of the definition. That common thing is called the Platonic
Form. As philosophers, it is our duty to capture the forms of such things as moral goodness,
love, justice, virtue, beauty truth, and knowledge in solid definitions.
To get a feel for Plato’s Theory of Forms, consider the thing you are sitting on. How would you
define it? Here’s an initial pass:
X is a chair = X is a piece of furniture designed to support sitting.
This definition is general enough to capture all chairs, despite how much chairs can vary in their
size, color, and material, and yet specific enough to distinguish it from other things, like beds,
tables, and sofas.
Forms and The Identity of Objects
Forms perform a dual function in Plato’s philosophy. First, they are the answers to the “What is
X?” question; they are the things that we aim for when we give philosophical definitions. In the
chair example, the form of a chair would be spelled out as “piece of furniture designed to support
sitting.” To keep things short, we’ll just call the form of a chair, CHAIR. Second, the forms are
the ideals or perfections that make their physical manifestations what they are. On this view, it is
because CHAIR is present in what you are sitting on that makes it a chair. Furthermore, it is the
element common to all different chairs spread out in time and space. We cannot use our senses
to perceive the form, but it is real. In fact, it is even more real than the things (individual chairs)
that exemplify it. In this regard, Plato follows Parmenides’s restriction on what counts as being
real; what counts as real are only those things that are eternal, unchanging, indestructible, and
imperceptible. In short, the forms are not only the things we aim to capture in our definitions.
Since this second idea is challenging, let us spend a bit more time reflecting upon it. For Plato,
the form of a thing makes the (physical) thing what it is. Forms give things their identity.
Suppose you are sitting on a wooden chair. For Plato, it is because that specific collection of
wooden pieces “participates” in CHAIR that this set of wooden pieces is a chair. Had it
participated in a different form, say the form of TABLE, then that set of wooden pieces would be
a table. On Plato’s view, the thing you are sitting on is a chair because there is an entity – the
perfect chair, the essence of a chair, (CHAIR) – that your chair possesses in some manner.
Physical chairs may vary in their size, shape, and material, but they are all chairs because of the
involvement of a single entity, CHAIR, in each of the individual chairs. The nature of how
physical objects manifest theory forms is a thorny issue that philosophers, even to this day, still
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have trouble understanding. Various terms are used to express the relation (which, in the
diagram below, is depicted with arrows): the objects “participate in,” “imitate,” “emulate,”
“instantiate,” the forms.
PLATO’S FORMS = TYPES:
repeatable, eternal, unchanging, indestructible, indivisible, singular.
CHAIRNESS
INSTANTIATIONS = TOKENS:
finite, changing, destructible, divisible, and diverse.
Every thing has a form that makes the thing the kind of thing it is. The thing you sleep in is a
bed because it “participates in” or “instantiates” BED. The things that grow on trees are leaves
because they “participate in” or “instantiate” LEAF. One item can have several forms, so a
single leaf can be LEAF, GREEN, ALIVE, etc.. But more important for Plato is to understand
that different things can have the same form that accounts for what they are. Thus, two separate
leaves may be slightly different in shape and color, but there is a single entity shared among
them – LEAF – that makes them leaves. Lincoln’s freeing the slaves, giving women the right to
vote, your staying up all night to take care of a sick friend, would all be good, according to Plato,
because each of these disparate things instantiates the GOOD.
THE ONE OVER MANY
Introduction to the Problem
Plato’s Theory of Forms is an attempt to solve a certain problem called the Problem of the One
Over the Many. Here is the problem in a nutshell. There are many things that share one and the
same feature: this blade of grass and that blade of grass have the feature of being a blade of
grass. This piece of chalk and that piece of paper have the feature of being white. Socrates and
Abe Lincoln are both wise. This electron over here and that electron over there are virtually
identical in all of their features. How are we to explain this phenomenon – that fact that among
many things, there appears to be just one thing they all have in common? This question brings
us to the problem of universals. To appreciate the problem, we need to go over some
terminology and distinctions.
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Types and Tokens
The type/token distinction is crucial for understanding the problem of the one over the many.
There is no denying that we place many individuals under a common “type.” The individuals are
“tokens” or “tokenings” of the types.
Individuals
a = Abe’s yellow lab
b = Bob’s yellow lab
c = yellow pepper
d = green pepper
e = green broccoli
f = loud dog
Classes → Types /Natural
1 = dog: {a, b,f}
2 = yellow: {a, b, c}
3 = vegetable: {c, d, e}
4 = color: {a, b, c, d, e}
5 = loud: {f}
6 = green:{d, e}
The question is what is the ontological status of these types? Are they universals or are they just
ways of grouping individuals. The commitment to universals is called realism. The denial of
universals is called nominalism.
Universals vs Particulars
A universal is repeatable whereas a particular is not. If whiteness is a universal, then it is an
entity that is wholly present in CHALK1 and wholly present in CHALK2; one and the same
entity is repeated across different individuals and is thus wholly present in different places at the
same time (as well as across time). A particular is isolated to a particular region of space and
time, if it is a concrete particular, or it is simply a singular entity “outside of” space and time, if it
is an abstract particular.
This is not the same distinction as the distinction between properties and the individuals that
have them. This latter distinction – property and individual – is a pre-philosophical distinction,
which makes up the analysandum. The distinction between universals and particulars is a
philosophical one that is applied to the pre-philosophical one when it comes time to determine
the nature of an individual and its features: is the package just a bundle of universals? Is it just a
bundle of particulars? Is it both, and if so, how do we explain how universals and particulars
make up the individuals and their features?
Realism: There exist universals: a1 … an’s being F is a matter of having one and the
same entity – a universal – wholly present in a1 … an
Nominalism: There exist only particulars: a1 … an’s being F is a matter of coming under
a concept (term), forming a class, or resemblance.
On the realize view, an individual a is F just in case there is an entity – F-ness, that is
instantiated by a. One problem with realism that that the entity has the unusual characteristic of
being cable of being in different places and at different times. No ordinary particular has this
capacity.
On the nominalist view, an individual a is F just in case there is a term “F” that applies to or is
true of a, so something is red if the term “red” applies to that thing. One problem with
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nominalism is that types depend for their existence upon the existence of cognizers, but it seems
implausible that types of things like the type TREE or ZEBRA or FROG, etc. exist only because
there happen to be humans who have concepts that classify these objects into these groups.
PLATO’S THEORY OF RECOLLECTION
Plato’s Theory of Recollection is a solution to the Problem of Analysis. The Problem, is
basically this:
1. We either already know the definition of X or we don’t.
2. If we already know the definition, then we don’t need to bother with giving a
definition since we already have it.
3. If we don’t know the definition of X, then we won’t be able to recognize it even it
is given to us.
The conclusion we are led to draw is that it would be pointless to try to give definitions. Plato’s
very provocative way of solving the problem is by claiming that we do, in fact, have knowledge
of the forms, but not in a way that is explicitly apparent to us. However, because the knowledge
is fully present in our souls, although kind of hidden from us, we can recognize it if we hit upon
it. Plato’s theory requires that we possess souls that are eternal and that have prior, non-mortal,
experience with the forms. Through this prior, non-mortal experience of the forms, we come to
know them in our souls, which we then promptly forget at birth. The rest of our mortal lives are
then a struggle to regain what we knew in our immortal state. The process by which we regain it
is though doing philosophy.
In essence, all learning of the forms is really a process of remembering what we already knew. It is
important to appreciate that this applies only to knowledge of the forms. It does not apply to
knowledge of trivial things, like the name of your neighbor’s dog, or the items you ate for breakfast.
It applies only to knowledge of the forms. The argument is best understood in two steps.
Step 1
1. We can gain knowledge of the forms only through the senses or through
intellect/reason.
2. We cannot gain knowledge of the forms through the senses.
3. We gain knowledge of the forms through the intellect.
This is a valid deductive argument in the form of a disjunctive syllogism. It appears that the first
premise is true: there are only two means by which we acquire knowledge – the senses and the
intellect/reason. Thus, the burden comes down to supporting the second premise.
Why Forms Can’t Be Perceived Through the Senses
According to Plato, reason is a faculty that belongs to the soul; the senses are faculties that
belong to the body. Reason is a faculty of thinking that is contrasted with the faculty of the
senses, as distinct from each other, as the heart differs from the liver. For Plato, the duty of a
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philosopher is to grasp the forms so that we may furnish solid definitions of them. How, then,
can we come to know the forms? Plato’s answer is that we can come to know the forms only
through reason, not through the senses. The senses only interfere with this endeavor.
To understand how reason or the intellect is involved, consider a pair of shoes that appear to be
of the same size. If you were to measure each shoe with high-precision instruments, one would
be slightly bigger than the other. Close scrutiny reveals that there are imperfections. However,
there is no doubt that you have the concept of equality and sameness firmly in your mind. How
did they get there? Surely not by the senses, since the physical world is full of flaws and
imperfections, and the senses can only report what is there in the physical world. Yet you have
the concepts or ideas of things that are never fully realized in any physical object. You have the
concept of EQUALITY or SAMENESS, despite the fact that no two things are exactly equal or
the same.
The same applies to all the forms: courage, beauty, justice, piety, virtue, wisdom, and pretty
much everything we care about. Nothing in the physical realm will actually have any of the
perfections. Yet we can intellectually grasp something we never literally see or touch. Plato’s
explanation of this situation is that we have a separate intellectual faculty, a faculty not affected
by or informed by the senses, which is the faculty of reason. It is through reason, and reason
alone, that we can grasp the forms.
We are now in the position to move onto the second step of the argument, the step that shows
that learning is recollection.
Learning is Recollection: The Slave Boy Does Geometry
Step 2
1. If we had knowledge of the forms all along, then its retrieval is a matter of
recollection.
2. We had knowledge of the forms all along.
3. The retrieval of knowledge is a matter of recollection.
This is a deductively valid argument (which uses modus ponens). The premise that calls for
support is Premise (2). Through the geometry lesson with the slave, Socrates demonstrates that
the Slave knew how to compute the diagonal of a square, just by “being reminded” of the
relevant facts through the proper method of questioning.
Modern Appropriations of the Recollection Argument
Contemporary cognitive science and the nativism hypothesis
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Language Learning
Depth Perception
Statistical Irregularities
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