Epistemology is the branch of
philosophy that deals with the nature of
knowledge and
truth. It encompasses the study of the origin,
nature, and limits of human knowledge. There are
various ways people approach this task; the following
categories originally reflected divisions among
schools of philosophy in the seventeenth and
eighteenth centuries, but are useful in categorizing
certain approximate trends throughout its history:
- (1) Rationalists (see
rationalism) believe there are innate ideas that
are not found in experience. These ideas exist
independently of any experience we may have. They
may in some way derive from the structure of the
human mind, or they may exist independently of the
mind. If they exist independently, they may be
understood by a human mind once it reaches a
necessary degree of sophistication
- (2) Empiricists (see:
empiricism,
scientific method,
philosophy of science
naive empiricism) deny that there exist any
concepts that exist prior to experience. For them,
all knowledge is a product of human learning, based
on human perception. Perception, however, is a cause
of concern since illusions, misunderstandings and
hallucinations prove that perception does not always
depict the world as it really is.
- A problem for empiricists is the existence of
mathematical theorems; their truths certainly do not
depend on experience, and they can be known prior to
experience. Empiricists rebut that all mathematical
theorems are empty of cognitive content, as they
only express the relationship of concepts to one
another. Rationalists would hold that such
relationships are indeed a form of cognitive
content.
- (3) The German philosopher
Immanuel Kant is widely understood as having
worked out a synthesis between these views. In
Kant's view people certainly do have knowledge that
is prior to experience, which is not devoid of
cognitive significance. For example, the principle
of causality. He held that there are a priori
synthetic concepts.
People in all schools of thought agree that we have
the capacity to think of questions that no possible
appeal to experience could answer. For instance: Is
there an end to
time? Is there a
God? Is the God of the philosophers the same as
the
Biblical God? Is there a reality beyond that which
we can sense? Such questions are termed
transcendental, as they seem to go beyond the
limits of rational inquiry. In the 20th century
logical positivists have declared such questions
to be totally devoid of cognitive significance. Others
disagree, and hold that only some metaphysical claims
are devoid of cognitive significance however some may
not be.
There is no consensus as to which epistemology will
be the most productive in allowing human beings to
have the most accurate understanding of the world.
While not widely appreciated, all people use an
epistemology, even if unconsciously. Thinking beings
cannot understand and analyze ideas without first
having a system to accept and analyze information in
the first place, which we all do. All people - even
children - possess rudimentary and undeveloped
epistemologies. However, only those who study some
philosophy and logic can begin to recognize how their
own epistemologies work; only they can choose to
change their epistemology, if they so wish.
Our analysis then will be dependent on the system
we used to begin with. One might wonder: What do I
have to do, to be sure that I do have the
truth? How can I be sure that my beliefs are
true? Is there some sort of guarantee available to me
-- some sort of criterion I might use, in order to
decide, as rationally and as carefully as I possibly
could, that indeed what I believe is true?
Suppose you thought your belief had been arrived at
rationally. You used
logic, you based your belief on
observation and
experiment, you conscientiously answered
objections, and so forth. So you conclude that your
belief is rational. Well if so, then your belief has
at least some claim to be true.
Rationality is a indicator of truth: if your
belief is rational, then it is at least probably
true. At the very least, the rationality of a belief
is reason to think the belief is true.
Now, there are a number of features of beliefs,
such as
rationality,
justification, and
probability, that are indicators of
truth. So let's define a general term:
A feature of belief is an epistemic feature
if it is at least some indication that the
belief is true.
Many of our beliefs do have lots of positive
epistemic features; many of our beliefs are quite
rational, quite justified, very probably true, highly
warranted, and so on. But most of us, at least in some
moments, don't want to rest content with just being
rational. We don't want to have a rational belief that
is, unfortunately, false. Because that's possible,
right? I can be very conscious, careful, and logical
in forming a belief, and so be rational in holding the
belief; but it still might be false. So rationality
isn't our ultimate ambition that we have for our
beliefs.
Our ultimate ambition for our beliefs is
knowledge. Because if I do know
something, then not only am I justified, or rational,
in a belief; because I have knowledge, I have
the truth. So naturally, when we are thinking about
the epistemic features of our beliefs, the big
question is this: When do I have knowledge?
When can I say that I have it? As I'm sure you are
aware, there are some people who claim that we
can't have knowledge; such people are called
skeptics. More on that, of course, later.
Now I can describe to you the field of
epistemology, which is also called the theory
of knowledge. Here is a definition:
Epistemology includes the study of (1) what
the epistemic features of belief, such as
justification and rationality, each are (e.g., what
justified belief is); (2) the origin or sources of
such features (and thus the sources of knowledge); (3)
what knowledge is, i.e., what epistemic features would
make a true belief knowledge; (4) whether it is
possible to have knowledge.
So, first, epistemologists spend a great deal of
time concerning themselves with various epistemic
features of belief, such as justification and
rationality. And they write long articles and books
trying to say just when beliefs are justified, or
rational.
A second, related concern is where such
epistemic features ultimately come from. If I say, for
example, that my belief that Paris is the capital of
France is justified, I can ask: Where did the
justification for my belief come from? Probably at
some point some reliable source told me that Paris is
the capital of France; and that was enough to make me
justified in adopting the belief. OK, then
one, but only one, source of justification
would be testimony, which is just a fancy word
for what other people tell me. Another source of
justification would be sense-perception. So
epistemology asks: What are the ultimate sources of
justification, rationality, or other epistemic
features of belief? And that allows to answer a
further question: What are the ultimate sources of
knowledge?
Which brings us to the third topic studied by
epistemologists, namely, what knowledge is. The
question here isn't what we can know, or even
what we do know. The question is: What would
knowledge be, if we had it? A belief has to pass some
sort of muster if it's to count as knowledge. So what
features would a belief have to have, in order to be
an actual piece of knowledge -- not just something
that pretends to be knowledge, but which is
actually knowledge?
Then, fourth, there is one of the more difficult
topics of philosophy -- trying to answer, or otherwise
deal with, the challenge that we cannot have
knowledge. A number of philosophers -- not too many,
but some -- have said that we cannot have knowledge. A
lot of philosophers have said that it's very
difficult to obtain knowledge; but they don't deny
that we have it, or that we can have it. Not so
many philosophers, however, have gone so far as to say
that we have no knowledge at all, or (to say something
even stronger) that it is impossible to have
knowledge.
See also
Self-evidence;
theory of justification;
the regress argument in epistemology;
a priori and a posterior knowledge;
knowledge;
scepticism;
Common sense and the Diallelus;
social epistemology
See also:
aesthetics,
Ethics,
Metaphysics,
Philosophy,
Ontology,
Reason