A Brief History of Epistemology

Heat.

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Heat.

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Pause for a moment and conjure up in

your mind something that you know for

certain, an indisputable fact.

Rain comes from clouds. Your mother's

first name.

Swans are white.

God is real. Then consider how is it

that I know this fact.

Am I depending on my senses to confirm

something is true?

Are they completely trustworthy?

Did I rely on someone else to tell me

this information?

Who told the person who told me?

Ask yourself, what does it mean to

really know something?

How can I know that I know it? When can

I be completely confident that my

beliefs about the world are justified?

Is seeing the same thing as believing?

Suppose

there's a vase on a table

and I look in the direction of the vase

but uh interposed between me and the

vase is a very very welldrawn

picture of a vase or a hologram of a

vase and what I actually see is that

picture or the hologram. So I look in

that direction,

there's uh a vase in that direction and

I come to believe on the basis of

looking at the picture that there is a

vase.

My belief that there's a vase in that

direction is true because there is one.

Uh and I certainly believe it strongly

enough and I think if you ask me uh do I

know that there's a vase there? I'd say

yes.

On the other hand, it's quite clear I'd

be wrong in saying that

what can be said about a vase can be

said about virtually every other aspect

of the world we live in. The

philosophical study of the nature and

the scope of what we can know is called

epistemology.

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There are two primary questions that

epistemology addresses. First, what if

anything do instances of knowledge have

in common? In other words, what is the

nature of knowledge?

And second, what is its scope? The

answer to these questions has tremendous

social implications.

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How can we know for certain someone is

guilty before we send them to prison or

even to their deaths? Do scientists push

the envelope of knowledge or are they

fabricating it as they go?

We rely on knowledge to weave the

tapestry of our daily lives. But how

dependable is what we take to be

knowledge?

We rely on newspapers. We rely on the

internet. Uh we rely on all of these

things. But how are these things

organized?

And how do people get the sources of

information that they get? Now we all

know that in totalitarian

uh situations

uh people have um are exposed only to

sources of public information that have

been approved of by uh dictators who

choose those and restrict these sources

uh to serve their own ends.

The first question that epistemology

must confront is what we mean when we

claim to know something.

I think we would say that the uh

automatic

door opener at a um grocery store knows

when somebody is approaching because it

opens.

Um, I think we might even say um that

one animal knows when another animal has

been there by a sense of smell. On the

other hand, we want to say um Newton

knew uh the law of gravitation.

And one of the questions is is there any

common notion of knowledge that would

cover all of those cases.

The human quest to define what we know

and how we know it begins at the

beginning with the classical Greek

philosophers

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in the republic. Plato examined the very

pragmatic issue of how it is that people

could lead good lives.

And it is this seemingly straightforward

question that led him to explore the

very headwaters of knowledge.

To emphasize that what we know must not

be acquired by mere accident. Plato gave

an analogy in which he compares

knowledge to the work of a highly

skilled artist.

Detilus was a sculptor who could make

semi-agical

um statues. When you approached them,

they would run away. And what Plato asks

is this, why do we so highly prize

knowledge? What is it about knowledge

that is so desirable?

Um it's much more desirable than just

mere true opinion or true belief. Um

now why is that?

And out comes the analogy. The analogy

is

knowledge is tethered true belief. We

want the statues not to run away. We

want our true beliefs not to want to run

away. We want them to be founded upon

something permanent.

The republic also contains Plato's

famous allegory of the line.

He asserted that knowledge can be

understood as a vertical line divided in

two unequal segments, each of which is

itself made up of two unequal parts.

The lower portion of the vertical line

represents knowledge received through

the senses that is opinions or beliefs.

The realm of the senses is further

divided into perceptions of visible

objects in this world on the one hand

and images and reflections of those

objects on the other

as mere copies of what exists. Images

and perceptions are the lowest forms of

knowledge.

The upper portion of the vertical line

represents the intelligible world. The

world of what Plato called the ideas or

forms, the true essence of reality.

This world can't be reached by the

senses. It is only accessible to reason.

Here there is another division between

provisional or incomplete knowledge on

the one hand and the complete knowledge

of the forms on the other.

Epistema, true knowledge, only comes at

this highest level where what is true

and what is real become one.

Much of what we now deal with under the

concept of truth versus falsehood. Plato

will deal with under the rubric of

authentic versus fake. And that that is

a serious difference in a way in in both

metaphysics and philosophy of language

and epistemology.

In his allegory of the cave, Plato gave

one of the most compelling accounts of

the relationship between truth and

authenticity.

Plato said, "Imagine a cave in which

people are tied down so that they can't

see behind them. They can only look

ahead at the back wall of the cave.

Behind them are others standing behind a

ledge. These people hold puppets over

the ledge.

Behind the puppeteers, there is a fire

whose light is projected onto the back

wall of the cave. The prisoners see the

shadows of the puppets. But since that's

all they know, they think these shadows

are reality, the essence of the world.

In fact, not only are the shadows not

real, but the puppets themselves are not

real.

Our

own account signifies that the soul of

every man does possess the power of

learning the truth and the organ to see

it with. And that just as one might have

to turn the whole body round in order

that the eye should see light instead of

darkness. So the entire soul must be

turned away from this changing world

until its eye can bear to contemplate

reality and that supreme splendor which

we have called the good.

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Aristotle was Plato's main student and

often his most penetrating critic.

He came to reject Plato's forms which he

felt were nothing more than abstractions

of actual things.

For Aristotle, individual and particular

entities are the only concrete reality

and true knowledge is gained through

intuition and experience.

We know the idea of a triangle by

abstracting common characteristics from

the triangles we have seen in our daily

lives.

Aristotle claimed that what ultimately

is real is not ideas or forms but rather

individuals.

Aristotle believes that uh uh human

beings are generally endowed with the

abilities uh to understand the world

around them more or less completely.

Some of course are better at it than

others. But where Plato would see people

as divided in different classes

according to their abilities. Aristoho

uh thinks it's only a matter of degree

rather than matter almost of the kind of

person. Actual knowledge is identical

with its object.

In the individual, potential knowledge

is in time prior to actual knowledge.

But in the universe as a whole, it is

not prior even in time.

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One attribute that the epistemologies of

Aristotle and Plato have in common is

that they both seek out the bedrock upon

which knowledge can be built.

In their view, our reasons for believing

something to be true rest on a structure

of basic beliefs

known as foundational propositions which

do not derive their justification from

other propositions.

This view is called foundationalism.

The main challenge to foundationalism,

first articulated by the Greek

philosopher Pyro of Ellis, is how do you

know when you've struck bedrock? At what

point does the chain of reasons stop?

Which reasons are true in and of

themselves?

Prons thought, okay, we get back to this

foundational proposition. And then I ask

you, why do you think that one's true?

and you say, 'Well, I don't have any

reason for that one.

Uh, and in fact, you go even further and

you say, I don't need a reason for that

one. Don't you see this is foundational?

And then the interlocutor can say, okay,

I see you think this proposition is

true, but you don't need a reason for

it. Is there something about this

proposition which is such that

propositions of that sort

are true even though you don't have a

reason for them? That you're entitled to

assert them even though you don't have a

reason. And you'll probably say, "Well,

yes, they're describing my sense

experience." you might say or you might

say um yes they're describing um mental

states to which I have access like pain

and what the peronian will do

uh is to say well do you think that you

have infallible access to your mental

states or to your sensations and either

you can say yes or you can say no

if You say yes, then the chain of

reasons stops. But this stopping point

is itself arbitrary and can't support

any subsequent links.

If you say no, then your chain of

reasons is infinitely long, in which

case you have an infinite regress and

your belief isn't justified by a

foundational proposition.

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If the chain goes in a loop, then you

have a circular argument. Anywhere you

go, you hit a brick wall. You are stuck

in epistemic regress. And the view that

this stuckness is unavoidable is called

skepticism.

The most fundamental problem about

knowledge we can raise is where does the

buck stop or does it just keep going?

Skeptics

saw that opposing arguments often seemed

to carry equal weight and believed that

the search for truth was an unending

process.

While this may seem a distressing

conclusion, their goal was actually to

achieve tranquility of mind by

suspending judgment altogether.

They rejected dogma in all its forms.

And skeptics since the time of pyro have

believed that all philosophical systems

are suspect because they far exceeded

the limits of what can be known.

The main basic principle of the skeptic

system is that of opposing to every

proposition an equal proposition.

For we believe that as a consequence of

this, we end by ceasing to dogmatize.

Despite the power of their arguments,

the skeptics failed to wipe out

foundationalism, and it continues to be

the most commonly held epistemological

view.

Foundationalism can take many forms such

as empiricism, the belief that knowledge

is gained through the senses or

rationalism which holds that some kinds

of knowledge are innate.

The French philosopher Renee Deart,

founder of the rationalist school,

believed that certain fundamental ideas

reside within our souls from birth, such

as the first principles of mathematics.

The world for Decart begins with the

self. All else is subject to doubt.

The self now in Decart's philosophy is

going to be the beginning of an entire

reconstruction of the world. Of course,

we know where it's going. It's going

toward this mechanistic view of the

world. Daycart believes that everything

can be explained in terms of size,

shape, and motion and in terms of the

soul, which is the self, the beginning

place of the reconstruction.

Um

this was philosophically of course an

important revolution.

Um and Daycart had many many followers.

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Though Decart is renowned for doubting

things from sensory experiences to his

own existence, his form of doubt was

different in kind from classical

skepticism.

A way to think of the difference between

the Peronian and Cartisian skeptic with

regard to the claim we do have knowledge

is the Cartisian skeptic denies it. Says

we don't have knowledge. The Peronian

says it's not clear to me whether we do

have knowledge or we don't have

knowledge. And so the Peronian would not

consider the Cartisian skeptic a skeptic

at all.

According to Deart, something known by

the natural light of reason cannot be

false.

What leads to error is not a lack of

reason, but rather a lack of method. If

mathematics has made great progress, if

logic is beyond reproach, if physics has

exposed the mysteries of the universe,

then it is because human reason is

capable of knowing the world around us.

The skeptics were wrong. With a good

method and enough time, there can be no

secrets kept from rational inquiry.

But among these ideas, some appear to me

to be innate, others advantitious, and

others to be made by myself facticious.

For as I have the power of conceiving

what is called a thing, or a truth, or a

thought, it seems to me that I hold this

power from no other source than my own

nature.

uh Daycart places a great deal of

emphasis upon um abstract reasoning

abilities and uh little emphasis on the

role of the senses or even denigrates

the role of the senses. Whereas uh

Francis Bacon and many who followed him

in Great Britain uh place much more

emphasis upon the role of the human

senses as uh the fundamental source of

input and uh treat reason as a

subsidiary faculty that largely just

organizes the material of the senses.

Francis Bacon was an early champion of

empiricism, putting his faith in the

senses as a solid foundation for

knowledge.

The three major empiricists were all

English. John Lockach, George Barkley,

and David Hume.

Though their views diverged greatly,

they each emphasized the fundamental

comprehensibility of the world.

They thought of the senses as yielding

impressions or ideas in the mind. Uh

where these were what we would you know

like visual appearances something

looking a certain color and looking to

be a certain shape and they conceived of

these data of sense to be uh states of

the mind or objects that are before the

mind and in the mind.

John Lockach was an enemy of tyranny in

all its forms and vehemently opposed

Decart's notion of innate ideas.

Lach argued that if general truths such

as logical and mathematical principles

were intrinsic, then a child would know

them without needing to be taught.

because it is devoid of innate ideas.

The human mind is like a blank sheet of

paper that is written upon by

experience.

According to Loach, an idea is any

representation we have in our minds.

What we have to do is um uh work with

experience and generalize from

experience. Um and because of that um um

there are things that we can never know

and there are other things that we can

know only imperfectly only to the extent

to which experience reveals them to us.

Follow a child from its birth and

observe the alterations that time makes.

And you shall find as the mind by the

senses comes more and more to be

furnished with ideas, he comes to be

more and more awake,

thinks more, the more it has matter to

think on. If it shall be demanded then

when a man begins to have any ideas, I

think the true answer is when he first

has any sensation.

The Irish clergyman George Barkley was

the next in line of the great English

empiricists.

Like Lach before him and Hume after him,

Barkley put his faith in the experience

of the senses.

But then they faced also the problem of

uh how can I go from what is in the mind

to what is out out there outside the

mind in the physical world and they saw

there was a problem and especially

Barkley saw there was a problem and his

move was very radical. So he saw no way

of making an inference from the ideas in

the mind to something completely

different from ideas. So he said

actually what other people call the

physical world that extern that's

external to the mind. He said that all

of it really resides in the mind. That

uh chairs and tables and all those

things that we think of as physical are

really things that exist in the mind.

The Scottish philosopher David Hume took

empiricism to its logical extreme.

According to Hume, perception is any

representation we may have in our minds.

There are two kinds of perceptions.

impressions which are strong and clear

and ideas which are weak copies of

impressions.

For example, seeing the color red is an

impression and remembering or imagining

it is an idea. Every impression leaves

its trace in the form of an idea and

every idea can be traced back to an

impression.

So one kind of impression are sensations

and Hume would take those to be basic.

Trace your justification back to

impressions and once you've done so you

can't go any further. Um and so you've

completed this kind of regress. So

you're back to the foundational

proposition. Um another uh source of

impressions for Hume not impressions of

the external world but impressions of my

own state. So I feel a pain for example.

Um or I'm feeling happy. Um those are

impressions but internal impressions

impressions of myself so to speak. So

impressions of the mind itself. And

again so you could trace your

justifications back to impressions of

that sort and then it's not there's no

point in going further. Hume would say

you couldn't go further.

The mind is a kind of theater, wrote

Hume,

where several perceptions successively

make their appearance.

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Hume believed that impressions can be

either simple or complex. A color, for

example, is a simple impression. But an

object such as an apple produces a

complex impression because it involves

other dimensions of experience as well,

such as shape, taste, and so on.

An idea may also be either simple or

complex. Many complex ideas don't begin

with experience, but rather are the

result of combining together in the

imagination simple or complex ideas

which do come from experience.

Hume called the relating of ideas in the

mind association. Association may be of

three kinds. Resemblance,

contiguity,

and causality.

When we look at somebody's picture and

think of the person in that picture,

that is resemblance. If we see a roof

from a window and assume there is a

house there, not just a roof, that is

contiguity.

Our expectation that certain events will

always follow other events is causality.

So suppose I take this pen out of my

pocket and I open my fingers and it

drops and I do that over and over and

over again. And I come to believe that

opening my fingers

is a sufficient cause given the way the

world is um for the pen to drop. So I

come to believe uh not only um has it

dropped in the past, it's going to drop

in the future. A human will say, "Look,

is it conceivable

um that the pen not drop? Could you

imagine the pen not dropping?" And yes,

I could I could imagine it not dropping.

So it isn't a priori that the pen's

going to drop. It's certainly true you

anticipate the pen dropping, but Hume

will say, "Do I have any reason for

thinking that if I open my fingers, the

the uh pen will drop?"

Hume held that the idea of causation

boils down to the impression of

anticipation that we have after

repeatedly experiencing the succession

of one type of event following another.

While we may conjoin everyday

occurrences in our minds, lightning

causes thunder, viruses cause disease,

the necessary connection between cause

and effect can't be established.

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When we look about us towards external

objects and consider the operation of

causes, we are never able in a single

instance to discover any power or

necessary connection, any quality which

binds the effect to the cause and

renders the one an infallible

consequence of the other. We only find

that the one does actually in fact

follow the other.

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Hume believed that while we may

anticipate events to follow in a

sequence, we can have no knowledge of a

necessary connection between them.

So does this mean that we can't relate

effects to causes in creating theories

about the world? If so, then what

becomes of science? One of our most

impressive foray into epistemology,

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the task of reconciling human skepticism

with cartisian subjectivity and in

effect making the world safe for knowing

again fell to an unassuming Prussian

philosopher named Emanuel Kant.

He believed that we all share certain

frameworks for understanding the world

which are real in that they exist in the

context of our minds.

Kant put the mind in a different

relation to reality than any of his

predecessors. This is um his

predecessors had uh thought of the mind

as a as a passive observer of reality

and had sort of looked around for some

kind of guarantee that it was a good

passive observer of re reality. Kant

prided himself on uh what he called the

capernac revolution in philosophy. the

idea that uh that actually the mind uh

structures the way reality can appear to

us and in a sense reality has to conform

to the laws of the mind rather than the

mind trying to to uh discover what

reality laws of reality are uh which are

completely external to it.

Unlike Hume can't believe that

scientific knowledge is universal and

necessary, not simply probable. But it

is a kind of universality and necessity

that lies within the world of phenomena.

Whether it exists in the world in itself

doesn't matter because we can't truly

know anything besides the contents of

our own minds.

Human reason has this peculiar fate that

in one species of its knowledge it is

burdened by questions which as

prescribed by the very nature of reason

itself it is not able to ignore but

which as transcending all its powers it

is also not able to answer.

At the beginning of the 20th century,

there began a revolution in philosophy

that became what is now known as

analytic philosophy.

The English philosopher Bertrren Russell

was at the forefront of this revolution.

Russell claimed that knowledge is an

overly vague term since it must include

both human and animal knowledge and

within human knowledge, it must include

both everyday and scientific knowledge.

Russell's colleague GE Moore held a

common sense view of knowledge. He

believed that the being of a thing is

independent from the knowledge we may

have of it.

Consciousness only reflects what is

real. Cartisian skepticism about the

external world simply isn't justified.

So elemental proofs that were

monumentally difficult for Deart proving

that your hands exist for example were

for Moore simplicity itself.

So how do I prove that they're hands

according to more this way? Here's one

hand here's another. I just prove that

there were two hands. What more do you

want? Um this is a view in philosophy

called direct realism.

Direct realism in this sense

m thinks that I can know things through

perception

without being able to prove them. In

other words, I don't need an argument to

know everything. It is a kind of

foundationalism.

Foundationalism that says, look, you

want to know whether there are hands.

How do you do that? You open your eyes

and you look. You don't give an argument

for the claim that there are hands.

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The Austrian philosopher Ludvid

Victenstein was an early pioneer in the

rigorous analysis of language in

philosophy.

He attempted to move the concept of

meaning from the fact or object

represented by words to the use given to

those words by a particular community.

reasoning.

As language only acquires meaning when

employed by people, any link between a

given word and its object depends on the

rules set by those who use that word.

These rules define what Victenstein

called language games.

He believed that all of us who engage in

the same language game employ here's a

hand as a bedrock proposition, one which

cannot under ordinary circumstances be

doubted because that is a fact about the

language game itself.

Vickinstein and and and other

philosophers who whom he influenced um

felt that philosophical questions are a

matter of language and it's a matter of

understanding our language better or our

language games that philosophical

puzzles arise because something has gone

wrong in our the language or maybe

because philosophers have started

misusing our language. G. Moore's common

sense epistemology was a form of

foundationalism.

The proposition that beliefs are

ultimately justified by irrefutable

foundational beliefs.

Coherentism rejects this view entirely.

A belief, say coherentists, can be

called knowledge when it fits together

with the rest of your beliefs.

They believe that justification is not a

linear process but rather a collection

of criteria that come together to

justify a system of beliefs.

The American philosopher Willard Van

Orman Quin described this as the web of

belief, a kind of seamless hole that is

never immune from revision.

In 1969, Quin wrote an article entitled

Epistemology Naturalized in which he put

forth a radical new vision of

epistemology.

How did it transpire that the senses

were bombarded by light waves and the

like uh and sound waves? And ultimately

they uh these same people who were

bombarded by lights and by sound issued

forth in various sentences that

formulated scientific theories. Or if we

can talk about beliefs that they came to

believe certain scientific theories

about the beginning of the cosmos, the

universe or about uh what happened to

the dinosaurs and so on. How did that

all happen? Well, that's a question for

basically how the mind works. Uh how uh

do beliefs form and theories form? So

that's a question for psychology. And uh

Quin said in a very radical way uh well

so epistemology should be part of

psychology.

The totality of our so-called knowledge

or beliefs from the most casual matters

of geography and history to the

profoundest laws of atomic physics or

even pure mathematics and logic is a

man-made fabric which impinges upon

experience only along the edges.

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Another major challenge to traditional

notions of epistemology came in the form

of a brief but penetrating article

written by the American philosopher

Edmund Getier.

Getier assaulted the idea of justified

belief with the following scenario.

Suppose two people Smith and Jones went

in for a job interview.

They're sitting next to each other

outside the boss's office. And as

they're waiting, Smith watches as Jones

counts the coins in her pocket. She has

10 coins.

Jones goes into the interview and just

then the boss walks by and tells Smith

that Jones is an old family friend and

there's no way she's not getting the

job. Smith is disappointed to be sure

and he mumbles disconulately to himself,

"The person who is getting the job has

10 coins in their pocket."

But now suppose the boss was just

kidding. And in fact, Smith was going to

be offered the job instead. And suppose,

unbeknownst to Smith, he himself has 10

coins in his pocket. While it's clear

that Smith's statement that the person

who is getting the job has 10 coins in

their pocket is in fact true, it's

equally clear that Smith does not know

that it is true. He had a justified true

belief, but he didn't have knowledge.

The unavoidable conclusion said get here

was that knowledge must be something

more than justified true belief.

After getier philosophers struggled to

find a new condition of knowledge.

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Traditionally epistemology had taken the

internalist view that everything

necessary to provide justification is

available to consciousness.

Decard and Loach, though worlds apart in

many ways, were both internalists in

that for them justification had to do

with internal states of conscious

awareness.

Externalism, by contrast, involves

factors external to the person. One of

the externalist theories that arose

after get here was the causal theory of

knowledge.

I proposed a rather radical u way to

solve the problem but not just solve the

getier problem but it was radical

because of other differences in the

approach that I put forward and and what

was popular at the time. So I propose

the causal theory of knowing. The idea

the rough idea being that if you

if your belief in your in your mind is

causally connected up in the in an

appropriate way with the fact that makes

what you believe true, then you know it.

But if it's not connected up in the

right way, then you don't know it.

Suppose I'm driving through the

countryside with my son and pointing out

different things. I said there's a cow

and uh there's a silo, there's a

farmhouse and there's a barn

and um you know these are ordinary

things. So what I point out uh is a cow

and is a horse and uh is a farmhouse and

so on and is a barn. Okay. But suppose

that although the barn I point out is a

regular old barn.

Unbeknownst to me in that very

neighborhood are lots and lots of other

things which look like barns but are

actually mere facades

say made of paperiermâché. And if you

went up close and walked around them

you'd find they're not real barns at

all. uh but mere papier-mâché facads

that from the road look exactly like a

barn.

If what he saw really was an ordinary

barn, then when he said, "There's a

barn," he spoke the truth. And not

knowing there was anything odd about

this district, he was justified in his

belief. However, in this district, just

looking out the window is not enough to

know there is a barn out there. In these

particular circumstances, looking out

the window is an unreliable way of

acquiring a belief about the barns that

dot the countryside.

Reliableism is the view that knowledge

is true belief that is justified in the

circumstances.

For example, Smith didn't know that the

person with 10 coins in their pocket was

going to get the job because his

conclusion linking the coins to the job

was not reliable in these circumstances.

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Reliableism is um a form of externalism.

The main form of externalism which says

that uh the reliability of a process or

a method can contribute to its

justification conferring power even if

you don't know know that it's reliable.

Uh whereas other people say well if you

don't know that it's reliable then it

can't be relevant.

Perhaps no other area of philosophy has

inspired the creative imaginations of

philosophers as much as the quest to

understand knowledge. Somehow this

project brings out the storyteller in

them, eliciting tales as varied as the

sublime allegory of the cave to the

serene tableau of barns dotting the

countryside. And yet, epistemology must

also contend with the powerful legacy of

skepticism.

With all the tales that have been told

and theories put forth, we have to ask

ourselves, what do we know about knowing

now that wasn't known in ancient Greece?

How dreadful knowledge of the truth can

be, wrote Sophocles, when there's no

help in the truth.