Introduction
In the Platonic dialogue, Theaetetus,
Socrates tackles the thorny issue of the unreliability of the senses.
What we perceive seems to makes sense on the surface; it feels like
the sense data is enough to deliver us the world in a clear and a
reliable way. That's what Theaetetus, Socrates's dialogue partner,
seems to initially believe. However, Socrates prods him with dilemmas
and puzzles to get him to see that appearances are not so
straightforward and that the more you think about how perceiving
works, the more confusing and difficult it seems to get the senses to
acquire knowledge and put together a coherent, logical picture of the
world. The process of the dialogue is just as important as the
content. Socrates gets Theaetetus to confront the difficulties of
perception and propose solutions. He places a premium on making the
young man reflect upon various alternatives and make choices as to
what seems right or wrong. Despite giving him lots of direction and
plenty of hints, he makes Theaetetus struggle to come up with answers
because he has faith in the inherent intelligence and power of the
mind to discover truths. In the paragraphs to come, I will first
explain why Socrates believes that Theaetetus's mind is capable of
penetrating the truth about the way perception can become knowledge.
I will then delve into the arguments he uses to convince Theaetetus
that acquiring knowledge requires not just perception but various
capacities of the mind. Lastly, I will illustrate Socrates's vision
of the necessity of the mind for coherent perception with examples
taken from everyday situations.
Giving Birth to
Ideas
In explaining how Theaetetus is
supposed to learn about perception and knowledge, Socrates embeds the
process of the generation of ideas within the mind in a mythological
foundation. You see, as Socrates would have it, ideas are born to men
like children are to women. Men's confusion and anxiety concerning
their lack of knowledge and inability to answer questions is the
equivalent to women's birth pangs that will eventually, after much
pain, produce the desired ideas. These ideas, born much like
children, won't always survive in the world as miscarriages happen.
Socrates takes it upon himself to tell his conversation partner that
the idea he has given birth to is not viable.
In this dialogue, Socrates thus
positions himself as a midwife to men's souls pregnant with ideas not
only as a way of making the painful process of arguing more palatable
but also in order to distance himself from the ideas towards which he
pushes his conversation partners. Since he says that the goddess
Artemis favors midwives that cannot give birth themselves, his own
mind is supposedly barren. The ideas that his interlocutors end up
articulating were born in their mind and not his. In a way, this
assertion of Socrates is quite disingenuous. Most of the time, it is
he who advances arguments and Theaetetus only assents or dissents to
them. To say that Theaetetus was the one that generated the ideas but
that his own role was merely that of assistance gives the young man
far more credit than he deserves. But then again, this assertion is
in accord with Plato's theory of recollection that postulates that
learning is the recollection of the soul's lost knowledge from its
previous lives. Citing glorious priests (a vague reference as they
aren't named) in the dialogue Meno, Socrates says: “The soul, then,
as being immortal, and having been born again many times, and having
seen all things that exist, whether in this world or in the world
below, has knowledge of them all; and it is no wonder that she should
be able to call to remembrance all that she ever knew about virtue,
and about everything.”
Knowledge is Subjective Because We
Perceive Differently
So, as Socrates accompanies Theaetetus
on a journey of rediscovering the hidden knowledge within his soul,
he is constantly rejecting those ideas of Theaetetus that he
perceives as miscarriages. Theaetetus initially equates knowledge
with perception. Socrates, who will later challenge this theory in
not only critical but disparaging terms, initially humors it,
probably for the sake of intellectual honesty. (After all, Socrates
is all for letting young men give birth to bad ideas; he wants them
to struggle before getting answers.) Now, in conceding the
plausibility of the equation of knowledge with perception, Socrates
draws on the theories of Protagoras and Heraclitus. Echoing the
legacy of Heraclitus, he proposes that the whole world is in a flux –
everything is in motion. No object is ever stuck at any position, it
or its elements are always moving from one position to another.
(Think of a moist object becoming dry and brittle – that is
“motion” that leads to change within the object.) In a world of
flux, perceptions are created when a causing object acts upon the
senses of a perceiver so that a sensation is produced. The motion of
light rays combine with the capturing action of the retina to create
the sensations of light. Whether red, purple, or gray, colors are
never stable “objects” at rest; they are a product of both the
motion of the sense of sight and the light affecting that sense,
neither of which will remain in the same position for long. All this
is cited by Socrates to support Protagoras's idea that the world is
what one perceives it to be. The senses and the unstable,
ever-fluctuating elements in motion acting upon them are caught up in
endless variation and cannot be pinned down or defined. Hence,
perception results in unique perceptions and experiences for every
perceiving agent. The varied background configurations that produce
each perception make the search for absolute knowledge that applies
to all untenable. (The belief in the subjectivity of perception
explains Protagoras's famous quote: “Man is the measure of all
things.”) The truth of wine and wind are to be found in the
perception of those experiencing them. Wine is neither sweet nor
bitter in an absolute sense and neither is wind cold or warm in an
absolute sense. Wind is cold for him who feels it be cold and warm
for him who feels it to be warm. For a healthy person, sweet-tasting
wine is sweet but not absolutely for everyone, since that same person
in a sick state experiences it as bitter.
Perception Needs Mind to Avoid
Confusion
However, if initially it seems that
Socrates allowed the theory of flux and motion to lead him to accept
that the perception of things in motion makes knowledge subjective,
he goes on to challenge this notion to show Theaetetus that his
first-born idea must be smothered in the womb. If perception is
constantly in flux and sensations always fluctuate, then perception
will be overwhelmed and confused. White can bleed into yellow, yellow
into red, and red into purple. It suffices to look at a detailed
painting to see how the surface is divided into a variety of tiny,
diverse shades of color. Or perhaps to stand in the sunlight and
watch how leaves, water, and grass have various different colors in
various spots depending on the way the light touches them. Even if
one tried to note every little pixel and its coloration, it wouldn't
be possible since the colors would change quickly, both based on the
rays of the sun and the position of the observer.
With all this in mind, Socrates argues
that the constant changes in the field of perception make perception
an unreliable candidate for knowledge. Based on pure perception,
things can't be identified and assigned properties. A windbreaker on
a hanger illuminated by a tall lamp seems beige at the top but seems
more dark and grayish towards the bottom away from the light.
Socrates asserts that perception by itself, without any assistance,
would be mired in this chaos of different sensations and wouldn't be
able to abstract them away to fix on one single object with a
continuous set of properties. (The varying colors of the windbreaker
could make it seem a set of various objects, each with its own
color.) The production of fixed objects and properties out of the
chaos of sensation, Socrates insists, would need the referral of
these perceptions to an entity that wouldn't only perceive but would
also be able to reflect upon the similarities and differences, the
unity and separateness within sense data. Cornered by Socrates to
consider how chaotic perception needs to be structured in order to
become coherent, Theaetetus concedes that “the
mind, by a power of her own, contemplates the universals in all
things,” thereby agreeing with Socrates's assertion that ”knowledge
does not consist in impressions of sense, but in reasoning about
them; in that only, and not in the mere impression, truth and being
can be attained.”
Real
Life Examples of Confused Perception
There
is no better example to illustrate Socrates's point than the way
babies perceive adults. When an adult dresses up in a costume that's
very different from his normal appearance, let's say a man that
attaches a fake mustache, puts on makeup, and wears clothes that are
unusual for him such as a toga or a dress, a baby may not be able to
identify this person despite knowing him well. An older child or an
adult, however, would not experience similar confusion and would
still be able to recognize the man. That is because, in addition to
pure perception, the adult and the older child are able to draw upon
the resources of his mind to compare the new appearance of the person
to his previous one and find the common features that would enable
them to equate the past and the present versions of the same man
despite their differences.
So what happens in order to make this
act of recognition possible? First of all, Socrates envisions the
mind as a block of wax on which we imprint our impressions. After
seeing objects and meeting people for the first time, we are able to
identify these objects and people instantaneously by matching our
perceptions with the images impressed in the mind. Imagine the case
of woman who caught the eye of a certain man at a party who later
changed into a ski mask and a different set of clothes to follow her
on her way home and rape her. She has already met the rapist at the
party but will she be able to recognize him in disguise? That depends
on the image that was imprinted on her mind. If she had paid
sufficiently close attention to him while at the party to be able to
remember a whole set of details about him, then it is more likely she
will recognize him. The clothes may be different and the face
concealed, but the body itself, as well as the voice and gestures
have remained the same.
Knowledge Based on Constitutive
Elements and Distinguishing Characteristics.
For this very reason, Socrates insists
on the quality of the image imprinted on the waxen block of the mind.
He stipulates that in order to have true knowledge you have to have
not only a vague image of an object or person but in fact be able to
list the elements that he or it are composed of. However, the key
point that Socrates makes is that in order to truly know and be able
to identify an object or a person, the elements that constitute it
must be retained with their distinguishing characteristics that would
enable the perceiver to exclude all similar objects of persons. That
is why upon finding a stolen car, the supposed owner of the car is
asked to list specific features of his car that could only belong to
his car and no other. Perhaps there is a special dent somewhere, a
stain from a hot drink or a marker. These distinguishing
characteristics are especially important in the recognition of
objects or beings that have changed over time. A set of puppies all
born at the same time may all be given separate names, but unless the
owner looks them over and finds that special little patch of color,
or the shape of a muzzle, he won't be able to remember which puppy is
which once they have grown. In all of these cases, it is not enough to just
recognize based on a vague or instinctive memory. That kind of
identification/recognition is only “true opinion.” True opinion
becomes knowledge only with an explanation that cites the
constitutive elements of the object/person as well as the
distinguishing characteristics. Thus for the woman above, to have
knowledge of the rapist, she will have to provide a set of his
characteristics, physical and otherwise, with one or several of them
specific enough that others would be unlikely to share it. For as
Socrates says, how can one know/identify Theaetetus by his snub nose
when there are others who also have a snub nose? Hence, the need for
the distinguishing characteristic.
The Mind's Mistakes in the Quest for
Knowledge
While Socrates spends a lot of time
talking about how the mind's attention to the elements and
distinguishing characteristics of things and people is what enables
it to successfully gain knowledge of objects, that is to identify and
recognize them, he also gives equal attention to how the mind either
fails to attain these objectives or experiences delays or impediments
in acquiring knowledge. And this failure happens at the stage where
we try to match the mental images in the waxen block of our mind to
the chaos of perception that invades our senses. For example,
distance may obscure or distort the appearance of someone to the
point that we match them up with wrong impression in our mind. Or we
fail to distinguish between two very similar items or beings, when
only one is present to our perception. Thus, if we happen to hear the
voices of two sisters that sound alike, when they are both there, we
may be reminded of the subtle difference between the two and identify
them correctly. When only one of the sisters is there, sister A, we
grasp onto to the aspects of her voice that are like the other
sister's and believe ourselves to be in the presence of sister B. The
failure to recognize something or someone we know may happen for a
simpler reason. Socrates conceives of the knowledge we possess as an
aviary of birds. The mental impressions that we have collected
throughout our life are flying around in our mind like birds but we
can't actively use them until we catch the bird. Hence when meeting
someone we haven't seen in many years, we are aware that the memory
of who they are is within us, but we have to roam around in the
aviary of our mind to get a hold of it. So we chase after that bird
and once we grasp it, we experience an aha moment of recovering lost
knowledge.
Conclusion
The goal of the dialogue is therefore
to establish knowledge on a secure basis and protect it against the
unreliability of perception. At the beginning, Socrates concedes to
chaotic conceptions of perception advanced by Heraclitus. He does not
fight the notion that the very same objects give rise to different
experiences of taste and color. Even shape and size of objects are
not secure as they can both change with time. He does believe,
however, that through the mind's power to contrast and compare, we
can penetrate different appearances and identify them with the
history of the same objects/beings that underlie them. A table can be
traced to its history as chopped wood and a tree. Milk can curdle,
wine can become acidic and bitter with time, but we can still
identify the curdled milk with fresh milk, the acidic wine with sweet
wine. Socrates is therefore contesting Protagoras's theory that
appearances dictate truth and therefore truth is subjective based on
individual perception. He postulating that out of diversity of
appearances, a steady set of absolute traits and features can be
derived that do not depend on subjective perceptions. (Hence “man
is not a measure of all things” like Protagoras would have it, but
things are as they are regardless of how man measures them.) Socrates
also manages to refute Heraclitus's view that everything is
ever-changing and therefore nothing is ever the same. Whereas
Heraclitus would say that you can't step in the same river twice
because it's completely different from what it used to be at a
previous moment, Socrates would say that despite the various changes
in the river, it has a set of constituve elements and distinguishing characteristics that
make it the same river as it was before. Just like there is something
about a person as a child that endures into his adulthood, even
though there are great differences between the younger and the older
version of the same person. Socrates would agree with Wordsworth that
“the child is the father of the man.”
Note: I am not sure if the assertions about wine and milk in my conclusion are factually valid. If you have any modifications to propose, send me a message.