We're now going to jump forward in time
about two thousand years and consider an entirely different set of
The history of western thought
is usually divided into four main periods, the ancient,
mediaeval, modern, and contemporary periods. We've been
studying the ancient period and now we're going to move past
the mediaeval period and into the modern period. The mediaeval
philosophers were concerned with a very wide range of philosophical
questions, but the focus of many of them was what we might call
metaphysical and/or theological. These questions largely concerned
the nature of the universe, how things are set up in the cosmos,
what part God plays in everything, how human beings should act
in order to be aligned with the ultimate laws of being, and so
on. These philosophies made claims about the ultimate nature
of being, about God, about human beings' place in the cosmos,
and similar themes.
At the beginning of the modern
period, though, some philosophers began to question these claims
and to wonder how anyone could know whether they were true or
not. This led to their wondering how it is that human beings
can know anything, and then to trying to figure out what counts
as true and real knowledge as opposed to mere opinion or belief.
This philosophical effort came to be termed "epistemology."
For example, consider the claim
that the earth is round. You would perhaps say that you "know"
the earth is round rather than that you just "believe"
the earth is round, or that it is merely your "opinion"
that the earth is round. But what would you say is the basis
for your knowing that? On what is your knowledge about the shape
of the earth founded? You have probably not personally been far
enough away from the earth to actually see its roundness, so
your knowledge is probably not based on direct personal experience.
Perhaps you have seen photographs of the earth from a distance,
but then in that case you are relying on what other people tell
you about those photographs, that they are actually photographs
of the earth, that they have not been tampered with to make the
earth appear round, etc. So your knowledge about the roundness
of the earth is partly grounded in your acceptance of the claims
of some people you take to be trustable authorities. You choose
to believe what they tell you. So your "knowing" about
the shape of the earth is partly grounded on some "beliefs"
you choose to accept.
The fact that many other people,
or even that most other people, share your beliefs does not actually
increase the likelihood that your beliefs are true. We all know
of beliefs that almost everyone in the past used to hold: for
example, almost everyone used to believe the earth was flat,
that the universe was only four or five thousand years old, that
women and slaves were inferior to adult males, and so on. These
beliefs are now not held by most people. Perhaps we should be
asking ourselves what beliefs we have today that in a century
or two will be considered not worthy of belief.
In any case, epistemology is the
study of how we know, what true knowledge is and what it is founded
on, what the differences might be between knowledge, belief and
opinion, and whether we can know anything at all with certitude.
The word "epistemology"
derives from the Greek word episteme, knowledge. Epistemology
is the ology, study of, what knowledge is and what
it is grounded on. (The Greek word sophia means "wisdom,"
and the word gnosis means "understanding," as
in the phrase gnothi seauton, "know thyself,"
or better: "understand thyself.") The word episteme
refers to what we might call simple information, data, or "factual"
knowledge. That is, it refers not to what we would call wisdom
and not to what we would call deep understanding, but refers
instead to knowledge of simple factual data. For example: How
many stories tall is the Sears Tower? What biological functions
does the kidney serve? What are the main differences between
tropical and desert vegetations? What is the second law of thermodynamics?
and so on.
So epistemology wants us to be
continually questioning what we think we "know," and
wants us to be asking ourselves what our knowledge is founded
For example, do you know what you
ate for dinner yesterday? If you do know, what would you say
that knowledge is based on? Perhaps you will say it is based
on your direct experience of eating it, but the more accurate
answer should probably be that your knowledge is based on a memory
experience you are presently having, a memory experience which
feels like it is an accurate memory of an experience you had
yesterday. But can our memories ever be mistaken about something
that happened yesterday? Is it possible for a person to have
a false memory about something they believe happened in the past?
Suppose you decide to trust your memory in this case, though.
If you do, then what you are in effect doing is deciding to "believe"
what your memory is telling you. So in effect your "knowledge"
about yesterday's dinner is based on a "belief" you
choose to have about the accuracy of your present memory. Your
belief about your memory's accuracy may turn out to be mistaken
in this case (you know your memory has been mistaken sometimes
in the past when you originally thought that it was remembering
correctly.) And yet, despite the fact that we all know memories
can be mistaken even when they feel like they are being accurate,
you are presently choosing to believe in the accuracy of your
memory about yesterday's dinner. How does a person decide when
to trust their memory and when not to?
Now most people do not like the
idea of trying to question everything they know or believe. The
epistemologists understand this, but they also understand how
important it is to try to find out what is actually, really true
in the world. It is important in the sciences, in the study of
history, in psychology and sociology, and even in daily events
in the world. What really actually did happen between Clarence
Thomas and Anita Hill, for example? How does the human immune
system really work? How does the brain actually work? Do breast
implants cause autoimmune diseases or not? Do pesticide residues
cause cancers and neurological diseases? Will it be possible
to make an effective HIV vaccine? And so on. We would rather
know the actual truth about these things, and not have to rely
only on opinions or beliefs.
Perhaps the most fruitful way to
approach some of the epistemological questions we will be exploring
this quarter will be to try questioning some of the beliefs that
we never question, beliefs that we all have and hold because
they seem so obvious to us. Let's consider a few examples of
these common beliefs.
Most people in the western world
believe that time is real, that it is not a human construct,
and that it actually exists out there in the world rather than
just in our brains. As we will see when we discuss the work
of Immanuel Kant (and others), there are some very important
reasons to doubt whether this belief is true or not.
2. We're here
Most people believe that they are
actually situated right where they think they are. You probably
believe that you are actually sitting right there in the room
and reading this text right now. You may have no doubts about
that at all. And yet it is possible that that belief is completely
wrong. It may be the case that you are not actually there right
now at all, but are actually asleep in your bed and only dreaming
that you are there. During a dream you are usually just as fully
convinced that what you are experiencing is real as you are convinced
right now that what you are experiencing is real. It is not always
possible to distinguish between what is a dream and what is reality.
Or perhaps it may be the case that
you are actually sitting in someone's office right now and that
you have just been hypnotized to believe that you are sitting
at home reading. Anyone who has ever been hypnotized realizes
how complete and real those illusion can be.
It may be the case, in other words,
that what you take to be an obvious fact -- viz., that you are
sitting and reading in that room right now -- may actually turn
out to be only an illusion. You may not actually be where you
think you are.
3. Stuff exists
Most people believe that physical
material things -- what we will call "stuff" -- actually
exists. This seems to be one of our most cherished beliefs in
the modern world, the belief in the real existence of physical
matter. We moderns might truthfully be termed "materialists,"
in the sense that we believe so dogmatically in the existence
of physical matter.
This belief in the physical existence
of material things is so deeply ingrained in us -- it is even
built into the very structure of many (but not all) languages
-- that it seems unquestionably obvious. We cannot imagine how
anyone with any sense could even consider doubting that physical
material things exist.
The belief in physical material
stuff is a dogma with us. We hold this belief dogmatically and
unquestioningly, and we consider it laughable and foolish that
anyone would question it. (In much the same way the flatness
of the earth seemed patently obvious to everyone a few centuries
ago, and it was thought that only fools would question it.)
What does it mean to hold to a
belief dogmatically? It means that we hold to it unquestioningly
and we consider it foolish and wrong to doubt that belief. (Not
all dogmas are religious ones, of course; many kinds of beliefs
are held dogmatically and unquestioningly.) One indication that
a belief is a dogmatic one for you is if you find it ludicrous
that someone would ever question it, or if it makes you slightly
irritated when someone seriously calls it into question. People
do not like to have their dogmatic beliefs questioned.
What the epistemologists would
want us to do is to be willing to examine and question all
of our beliefs, especially the ones we most take for granted,
and those to which we have become most strongly attached. Unless
we are willing to question these beliefs, we will not ever make
progress in our understanding of the world. It was important,
for example, to question our dogmatic belief in the flatness
of the earth, and also to question our dogmatic belief that the
earth was the center of the universe. Without questioning even
these most obvious beliefs, beliefs that virtually everyone held,
we would never have made any progress in our understanding of
Our next class project, then, will be
to try to seriously question one of our most cherished beliefs
probably a dogmatic belief for many people - that physical stuff
exists. To help in this effort, you can turn now to the
mini-lecture "On Stuff."