Modern Platonic Realism
Someone has asked me to discuss the Problem of Universals. The
trouble is, I don't see a problem. Universals quite obviously exist,
although we ought to give credit where credit is due and return to
calling them Forms. The basic phenomena philosophers who talk about
Universals are trying to explain are the similar properties shared by
objects. For example, this computer screen is white. My refrigerator
is white. All the walls in my apartment are white. In fact, it has a
sort of institutional feel to it. But what is this “white”
that surrounds me? Well, it's a color, an abstract property that many
things share. These abstract properties are called “Universals”
or “Forms”.
There are three basic strategies to dealing with these abstract
ideas – Realism, which accepts that these similarities between
concrete items as really real; Nominalism, which accepts that there
are similarities between concrete items, but denies that these
similarities are real things themselves; and Anti-Realism, an extreme
variety of Nominalism that denies that these similarities even exist.
1.a The Nominalist (Austere flavor)
Nominalism is often characterized as an attempt to respond to the
supposed problems of Realism. This is rubbish. The Austere Nominalism
of the modern philosopher rejects Plato's forms as unnecessary. It is
enough to say that there are similarities between things – no
further explanation is necessary. What I perceive with my senses is
enough. It was specifically this viewpoint that Plato responded to in
the Theaetetus (with Socrates conversing with the title
character):
THE: Well, Socrates, after such encouragement from you,
it would hardly be decent for anyone not to try his hardest to say
what he has in him. Very well then. It seems to me that a man who
knows something perceives what he knows, and the way it appears at
present, at any rate, is that knowledge is simply perception.
SOC:
There's a good frank answer, my son. That's the way to speak one's
mind. But come now, let us look at this thing together, and see
whether what we have here is really fertile or a mere wind-egg. You
hold that knowledge is perception?
THE: Yes.
SOC: But look
here, this is no ordinary account of knowledge you've come out with:
it's what Protagoras used to maintain. He said the very same thing,
only he put it in rather a different way. For he says, you know, that
'Man is the measure of all things: of the things which are, that they
are, and of the things which are not, that they are not.' You have
read this, of course?
THE: Yes, often. (151e-1521
Socrates then goes on to analyze precisely what this claim must
mean, and shows conclusively that what we know is not our mere
perceptions, but beliefs. And we can only have correct beliefs if we
are willing to embrace the Forms – without them we literally
cannot speak of anything because our only guiding principles are our
own perceptions. As soon as we begin to discuss anything we tacitly
acknowledge them. I can think about “my walls being white”
and deny that the thought has any connection to a reality outside of
myself. As soon I communicate the idea to you, I am appealing to a
third thing – a set of ideas that we share in common – in
this case, we are mutually accessing the ideas of “wall”
and “white”.
Austere Nominalists are usually stubborn folk, however, and one
may persist in insisting that these similarities and resemblances
between concrete things are mere brute facts and not larger
connections. One could explain that this is just how the universe
works, and it bears out no further explanation. It is perhaps
mysterious that one could acknowledge that the white of my walls is
the same as the white of my neighbor's walls without ever
acknowledging that that “white” is thing itself. But
people can, and do. These holdouts, one must presume, are not
interested in learning about the Theory of Gravity either, content as
they must be to simply explain “shit falls when I drop it”.
1.b The Realist (Platonic flavor)
Although the conclusions that Plato would draw from his Theory of
the Forms are sometimes complicated, off base, or just plain wrong –
the theory itself is beautifully simple, explanatory, and does not
carry nearly the metaphysical or ontological baggage that later
philosophers ascribe to it. The Forms are present in all of Plato's
dialogues, but their inclusion is often so innocuous and
uncontroversial that the average reader will agree with Plato's
argument while denying that s/he believes in something as silly as
“Platonic Forms”! As a preface to a larger argument (to
be dealt with below), Socrates explains the forms to Cebes in the
Phaedo:
We are altogether agreed then, he said that an opposite
will never be opposite to itself.–Entirely agreed.
Consider
then whether you will agree to this further point. There is something
you call hot and something you call cold.–There is.
Are they
the same as what you call snow and fire?–By Zeus, no.
So the
hot is something other than fire, and the cold is something other
than snow?–Yes.
[…]
It is true then about some of
these things that not only the Form itself deserves its own name for
all time, but there is something else that is not the Form but has
its character wherever it exists.
This bit about the Form existing for “all time” allows
Plato to argue for the immortality of the soul, but also provides the
impetus for many of the objections raised to the theory. It is,
strictly speaking, unnecessary to the Theory of the Forms itself,
although it is necessary for many of the arguments Plato constructs
based around them.
1.c The Anti-Realist (Metalinguistic flavor)
There are also some who dismiss the idea of similarities between
objects entirely. Some claim that when we discuss universals, we are
really discussing words. Any talk of universals is mere human
projection of beliefs we create onto reality. There are many ways of
making this argument, but the basic point they all share is the
refutation of realism by linguistic analysis. This is an intuitive
view, which one expects would be favored by those seeking the least
necessary components of a coherent belief system. We already have
words, so why invent more abstractions? But sometimes simplicity's
razor cuts too deeply.2
In the Cratylus, Socrates is discussing etymology with
Hermogenes and the title character. They reach a point of accord,
where all admit that names are properly determined by rule-makers and
taught to students based on the definitions provided by these
rule-makers, just as modern semantic philosophers might determine
that names mean what they mean by their proper usage within the
linguistic community. But Socrates continues:
SOC: Come now, consider where a rule-setter looks in
giving names. Use the previous discussion as your guide. Where does a
carpenter look in making a shuttle? Isn't it to that sort of thing
whose nature is to weave?
HER: Certainly.
SOC: Suppose the
shuttle breaks while he's making it. Will he make another looking to
the broken one? Or will be look to the very form to which he looked
in making the one he broke?
HER: In my view, he will look to the
form.
SOC: Then it would be absolutely right to call that what a
shuttle itself is. (389a-b)
Socrates and his interlocutors continue their discussion, but the
point is made – it is not the name of a thing (“Shuttle”),
or the thing (the broken shuttle), but the form of the thing
which is the thing itself.
If the meta-linguistic types were to persist, I might remind them
of the actions of a dog – any dog can distinguish between
humans and dogs and trees and rain and the like. If similarities
between concrete particulars are mere linguistic ephemera, how can a
being with no language detect them?
2 Platonic Realism: Problems and Solutions
The preceding section was meant to explain the general impetus for
believing in Universals, and discussed some competing views in an
obviously biased manner. The following section will address some
specific criticisms of Platonic Realism.
2.a Aristotle and The Third Man
The greatest challenger to Plato's Theory of the Forms during his
lifetime was not Nominalism – it was Aristotle's version of
Realism. Due to Raphael's painting, The School of Athens,
Plato's forms are usually characterized as being transcendent,
existing in “Plato's Heaven”. Aristotle, on the other
hand3 is said to have believed his forms were “down
here”, “in the things themselves”, or “immanent”.
Aristotle's Realism was actually fairly similar to Plato's, in that
both of them believed the forms were completely abstract. Where they
parted ways was in Aristotle's system of categorization of the Forms,
and his belief in the interplay between Form and Matter. While the
primary virtue of Aristotle's system is that it lends itself very
well to analogies regarding bronze statues, he may also have created
his taxonomy with an eye towards the “Third Man” argument
in the Parmenides (indeed, Plato named one of the characters
in this dialogue after Aristotle). The argument is too long to
excerpt (131-133b), but the basic point that Parmenides makes is that
Socrates's immature theory of the forms could fall prey to a
recursive loop.
Say, for example, that I have a thing y that has the property x.
So, y has x-ness. Now there is a relationship “having x-ness”
in addition to the property of x. So y has “x-ness” and
“y has x-ness” has “having x-ness”. Soon
enough we will discover that y has “x-ness”, and “y
has x-ness” has “having x-ness” and has “'(y
has x-ness) has having x-ness' having 'having x-ness'”, and so
on, ad infinitum. Plato clearly did not find this argument
convincing, writing it out in his own dialogue and leaving it as a
lesson for the student to solve. He later went on to write several
more dialogues featuring the older Socrates and his fully formed
Theory of the Forms.
There are two easy answers to this puzzle, and many more that are
being endlessly discussed somewhere by people who like to play word
games. The first reaction is to punt – the instantiation
relationship between a thing and the form of that thing may be a form
itself, the form of instantiation. This form could determine
the proper relationship between things and forms and ensure that no
monkey business of this sort was taking place. The second reaction is
to say “so what?” Abstract ideas are by their nature
limitless. Trying to limit the amount of Forms we can perceive is
like limiting the amount of numbers we can perceive. The “Third
Man”4 might be an interesting wrinkle in the Forms,
but it certainly doesn't disprove them.
2.b Humean Paradigms
One of the more Anti-Realist responses to Realism is David Hume's
theory of Paradigm resemblances. To refer back to the selection from
the Phaedo above, Hume would argue that “cold” and
“hot” are not distinctive things operating in the ether
without snow and fire, but rather that they are examples or paradigms
that we hold in our memories due to our exposure to the
aforementioned physical objects. In the Problems of Philosophy,
Bertrand Russell showed that Hume's argument has an obvious flaw
because the relationship between our memory of a paradigm and
new things we experience is itself a universal. For some
reason Russell tries to appear clever and claims that this idea of a
relationship as a universal is a new idea. It isn't, in fact
it appears all throughout Plato's dialogues.
The real question then, is why did Hume bother with such an
obviously flawed argument? One answer could be that the conclusions
drawn by the Forms were too much for him. In the Phaedo, after
Socrates has established that cold exists for “all time”
with or without snow, he uses that to prove that he too will live on
as a soul in the afterlife. This was problematic for Hume, but it is
even more problematic for us, since we are beginning to learn the
materialistic mechanisms by which the human brain associates ideas –
and an immortal soul does not appear to be part of the equation.
2.c Recollection? Not a Problem.
One of the more questionable components of Plato's theory of the
Forms is the doctrine of recollection, as expressed in the
Meno. But look at the actual objection that Meno makes to
Socrates's ability to discover what virtue is:
MENO: How will you look for it, Socrates, when you do not
know at all what it is? How will you aim to search for something you
do not know at all? If you should meet with it, how will you know
that this is the thing that you did not know?
SOC: I know what you
want to say, Meno. Do you realize what a debater's argument you are
bringing up, that a man cannot search either for what he knows or for
what he does not know? He cannot search for what he knows—since
he knows it, there is no need to search—nor for what he does
not know, for he does not know what to look for. (80d-e)
To be sure, the idea that we were once all immortal baby souls in
heaven, knew everything, and are just trying to remember what we once
knew is a bit ridiculous (especially in the light of modern science).
But that isn't the point! The argument that takes up the rest of the
Meno is Socrates teaching a slave boy geometry, to prove the
point that people can learn. We can easily abandon the silly
metaphysics of the “Platonic Heaven” in favor of modern
physics and biochemistry, but the arguments for the Forms themselves,
those non-physical objects of knowledge, those ideas are still valid.
3 Austere Realism
It should be clear that my own view of “Universals”
matches up closely with the view expressed by Plato two and a half
millenniums ago. But my view is different from his in two important
ways.
Firstly, I value metaphors. But it is important, especially when
discussing the “really real”, to draw a distinction
between the actual and the elaborative. To the extent that Plato's
arguments for the forms rely upon supernatural metaphors, be it the
recollection of the Meno, or the transcendent enlightenment of
the Philosopher-Kings in the Republic, I regard these as
merely metaphors. And any conclusions he draws from those particular
supernatural fables (such as the immortality of the soul, or the
superiority of an Oligarchic Government) are suspect.
The second difference I have with Plato is his belief that the
forms are eternal. The fundamental property of the Forms, as Plato
describes them himself, is that they are abstract. They are not
tangible. Most people can understand that this means they lack
dimension – height, width, and depth. What most forget is that
time itself is merely a fourth dimension. The Forms exist outside of
spatial reality – this means that they exist outside of
temporal reality as well. This does not mean that they are eternal,
it means that time is a meaningless concept when one is
considering the Forms. They are objects of knowledge that assist us
in better understanding physical reality – but they are fully
apart from it.
With a few minor alterations, Plato's Theory of the Forms can
survive the harshest of criticisms, both Ancient and Modern. The
granddaddy of all metaphysical theories is still the king, baby.
1. John M. Cooper, editor, Plato Complete Works (Indianapolis:
Hackett Publishing Company, 1997)
All subsequent citations are also from this source.
2. William of Ockham, I'm looking at YOU.
3. Literally, check out the painting: http://en.wikipedia.org/wiki/Image:Sanzio_01.jpg
For 500 years, their philosophical differences have been caricaturized by hand gestures.
4. But why is it called the “Third Man” Argument? Because every time you have the thing and the form, you're sticking a third guy on there. Also, Aristotle usually used the form of “man” to illustrate the argument.