Epistemology: Some Key Terms and Concepts
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Creative Commons Attribution-NonCommercial 4.0,
James DiGiovanna, Jan. 2014
These are just a FEW of the important terms and concepts we’ll work with. Much more to come!
Knowledge
Epistemology is the study of knowledge, and defining “knowledge” has been one of the key
tasks of the field. There is large scale disagreement on many parts of the definition, but most
(though by no means all) philosophers hold that for something to be knowledge, it must at least
be a Justified True Belief (JTB). Most hold that this is not a sufficient set of conditions for
knowledge: that is, something could be a justified, true belief and still not be knowledge, but
nothing could be knowledge unless it is at least a justified, true belief.
Three commonly (but not universally) accepted necessary conditions for knowledge:
Justified
A belief is justified if there is a
good reason to hold it. So if I
just have a vague feeling that
it’s going to rain, I probably
don’t have a very good
justification for my belief that
it is going to rain. On the other
hand, if I’m a meteorologist
and I’ve detected a weather
pattern that results in rain
99.99% of the time, then I do
have a good justification for
my belief that it will rain.
Most of the work of
epistemologists is focused on
the question of justification.
“True” and “truth” are handled
more often by metaphysicians
(another branch of
philosophy) and the nature of
belief occurs more frequently
in philosophy of psychology
or philosophy of mind.
True
A belief is true if, and only if,
the object of that belief is in
fact the case. “True” is one of
the hardest terms to define in
philosophy, but Aristotle may
have put it best when he said,
“to say of what is not, that it is
not, and of what is, that it is, is
truth.” “True” is an adjective
that pertains to some
sentences, and to some things
that can be expressed in
sentences, like beliefs. We
generally do not use it in
philosophy to describe nonsentential (non-sentence-like)
objects, though it can be used
to describe larger sets of
sentences (“that theory is
true,” for example.) If you
believe that the earth is a cube,
your belief is false. If you
believe that water is composed
of oxygen and hydrogen, your
belief is true.
Belief
A belief is something that is
held to be true, or held to be
the case. In short, anything
you believe is a belief. So if
you believe that you are sitting
in this room, then you hold the
belief “I am sitting in this
room.” Most of our beliefs are
mundane like this: almost
everyone believes that people
can be injured if cut, that
without food we will die, that
the sun rises in the morning
and sets at night, etc. Some
people reserve “belief” for
beliefs concerning objects of
ultimate value, or objects that
cannot be known with
certainty, but in philosophy
we just generally mean by
belief: that which I hold to be
the case.
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Four types of theories of justification:
Coherentism
Coherentism is the philosophical doctrine
that holds that a belief is justified if it
coheres with a large set of other beliefs. By
“coheres with” we mean “does not contradict
and is not contrary to any of the other
beliefs, nor to any inference from the set of
beliefs.” If my total belief set were “today is
Wednesday,” and “every Wednesday a dog
barks at me,” and I then added the belief
“today no dog will bark at me,” my belief set
would be incoherent. Coherentists assume
that if a new belief coheres with a large
existing set of beliefs, it is most likely to be
true (though not necessarily guaranteed to be
true), and therefore it is justified. In short,
every belief in a system of beliefs justifies
every other belief, forming a large web or
circle of justification.
Foundationalism
Foundationalists hold that a belief is justified by
either being in a set of foundational beliefs or by
being derived from such a set of foundational
beliefs, either by deduction or induction.
Foundational beliefs are generally ones that
cannot, by their nature, be doubted, or which are
almost completely incapable of being false.
These beliefs might be something like “right
now I am experiencing a tingling sensation” or
“I exist” or “A = A.” Such supposedly
indubitable (undoubtable) beliefs as “I feel a
pain. I am experiencing visual sensations as of
an arm that is bleeding. The arm appears to be
connected to my body,” can lead us to the highly
likely conclusion, “my arm is injured,” but that
highly likely (but still doubtable, or “dubitable”)
conclusion is justified only insofar as it rests on
the foundation of indubitable beliefs.
Infinitism
Infinitism holds that the chain of justification
can extend infinitely. This is a response to
the regress problem, that is, the problem
that every time you answer the question
“how do you know that?” someone can ask
the question again about your answer.
Whereas the foundationalists hold that a
chain of justifying reasons must come to an
end in a foundation, and the coherentists
hold that the chain loops around in a circle,
the infinitists hold that it goes on forever.
Virtue Epistemology
Virtue epistemologists hold that a true belief
counts as knowledge when it is acquired as the
result of an intellectual virtue. That is, if the
knowledge is the result of some virtuous (i.e.
well-functioning) process, such as: having good
eyesight and sound judgment; understanding
what sources are good sources for information;
being able to distinguish different sorts of
noises; knowing how to do a scientific
experiment; etc. Virtue epistemologies are
usually further divided into reliablilist and
responsibilist versions. Reliabilists hold that a
belief is justified if it was acquired by a reliable
belief-forming system (e.g. a belief about
something seen acquired by someone with good
vision); responsibilists hold that a belief is
justified if it was acquired by a responsible belief
forming system (e.g. a belief about a scientific
claim acquired by responsibly looking through
and reviewing the scientific literature.) One can
accept both theories as pertaining to different
sorts of claims.
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Locations for justification:
Internalism
Internalists hold that the justification for
knowledge must be accessible to the knower by
introspection, that is, by examining the
contents of one’s own mind. Suppose that I can
reliably tell you the correct temperature every
time you ask, but I have no idea how I can do
that, and further, don’t even know that I reliably
do so. An internalist would hold that I then do
not know the temperature. However, if you
know me to always reliably tell the correct
temperature, and you ask me, and I tell you,
then you would know, because you would have
access to the justification for your knowledge
(i.e., “I checked a reliable source.”). Internalists
often accept “KK” or “knows that knows that,”
the principle that if you know something, you
know that you know it. Many contemporary
philosophers reject this principle.
Externalism
Externalist hold that the justification for
knowing needn’t be introspectively available
to the knower. The externalist might accept,
for example, that a person who always
reliably told the correct temperature would
accurately be said to know the temperature
even if he or she didn’t know how he or she
was correct about the temperature, and was
not aware of the fact that he or she always
gave the correct temperature. Reliabilism is
a form of externalism, but there are other
forms. Externalists accept that some
justifications are knowable by introspection,
and that some parts of some justifications are
knowable by introspection. They just hold
that sometimes, and to some extent,
justifications can be external to the conscious
mind.
Some Different types of knowledge
Know-how
Know-how is what it sounds like: knowing how
to do something. For example, you might know
how to throw a curve-ball in baseball, but not be
able to explain how you do it. Or your knowhow might be highly mixed with know-that: you
might know how to paint a likeness, and be able
to explain what you are doing, but that doesn’t
mean that someone who hears what you say can
simply paint the picture. Other examples:
knowing how to tell a joke, knowing how to
perform an experiment, knowing how to teach
math. Many hold that know-how extends
beyond know-that, or is a separate faculty.
Intellectualists hold that know-how always
includes some know-that.
Know-that
This is generally understood as knowing certain
propositions, that is, the sorts of things that are
expressed in sentences. You might know that
1+1=2, or that John Jay was the first Chief
Justice of the Supreme Court, or that paper is
made from pulped wood. Specific instances of
know-that can generally be put in the form “S
knows that P,” where S is a subject (generally a
person) and P is a proposition. “Keisha knows
that protons are composed of quarks.”
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A priori
A posteriori
A priori (“from the earlier” or “from what
A posteriori (“from the later” or “from what
comes before”) knowledge is knowledge you
comes after”) knowledge is knowledge that is
can acquire without experience, generally by
gained from experience. If I say “it is raining
reflection or simply by being conscious and
outside,” I probably know that because I
thinking. For example, it should be obvious
looked out the window and saw rain, or had
that “If all horse are gray, then all horses are
some similar experience. That would then
gray” is true. Similarly, “either all horses are
count as a posteriori knowledge. My beliefs
gray, or not all horses are gray,” is true by the
about what color the sky is, how many fingers
mere form of the statement, and not by any
I have on my left hand, whether or not heavy
experience in the world. I’m a priori justified
objects fall at the same rate as light objects,
in believing some proposition if I have no need etc., are probably all derived a posteriori.
of any particular experience to guarantee its
truth. Some philosophers reject the claim that
there is any truly a priori knowledge.
Some Categories for Sources of knowledge:
Introspection
Perception
Introspection is the act of “looking in” to one’s Perception is the process of taking in sense
mind. Many philosophers hold that I can
data in some meaningful form. Sense data is
introspect all sorts of information about my
whatever comes to us through our senses. So if
mental states: for example, that I am angry,
a red ball is held in front of my open, normally
that I am having a visual experience of redness, functioning eyes in good light, and I’m not on
that I think, etc. There is some controversy
drugs or hypnotized or terribly distracted or
over how accurate our introspection is, with
some such, there’s a good chance that I’ll
traditional philosophers often holding that we
perceive the red ball, or at least have an
have some infallible introspections, and some
experience of perceiving a red, round shape.
contemporary philosophers narrowing down
the range of, or eliminating, that infallibility.
Intuition
The Given
Philosophers use “intuition” in two ways:
“The given” is the name given to the
a. An immediate, direct knowledge of
putative immediately available bits of
something, without need of justification,
knowledge or knowledge-elements (things
and without any sense of how the thing is
that form a part of knowledge) that require
known. Descartes holds that we know that
in themselves no justification and come
we exist by immediate intuition.
prior to any categories of the mind. Lots of
b. A mental state in which some proposition
philosophers reject the idea that there are
seems to be immediately and obviously true. “givens” in this sense. The main candidate
A general disposition to believe some
for the given is usually sense data: that is,
particular proposition.
whatever hits the senses prior to its being
The “a” cases are meant to be indubitable; the “b”
interpreted by the mind. But a Cartesian
cases are simply unexamined, and could be
intuition of self-existence would also be a
doubted. The “a” cases can be considered sources
case of the given.
of knowledge, and are thought by some to be
foundational.
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Testimony
Since it seems impossible that all of our knowledge is acquired first-hand, through perception, intuition,
introspection, or some innate source, it must be the case that at least some (and perhaps most) of our
knowledge is acquired second-hand, that is, from others. The philosopher Bertrand Russell distinguished
between knowledge by acquaintance and knowledge by description. The former would be any sort of
direct knowledge obtained by experience with the thing known. The latter would be the sort of knowledge
we get by reading about or hearing some topic. Much of epistemology is concerned only with knowledge
by acquaintance, and the above 4 categories generally refer to this kind of knowledge. More recently,
philosophers have looked more closely at the importance of what is now called “testimony,” that is, the
presentation of knowledge by a knower to a subject who may become informed by this presentation. This
is not a new concept, but there is a recent weight of investigation upon it, and many philosophers now
look at problems of testimonial knowledge, focusing on questions of trust and trustworthiness, the social
nature of knowledge, knowledge communities (such as, for example, the community of physicists, or
medical professionals, or people who care for children), the way certain communities have been excluded
from presentations of knowledge (for example: women’s knowledge, the knowledge of the poor, and the
knowledge of those outside the mainstreams of society, have often been devalued), which leads to
questions of what is now called “epistemic injustice,” that is, failing to accord the level of trust that is
appropriate to a knower’s testimony simply because the knower is not a member of a favored group.
Limits and Problems
Skepticism (also spelled “scepticism.”)
Skepticism is either the belief that some or
some kinds or even all knowledge is
impossible, or the refusal to assent to any nonevident proposition, or the refusal to take a
position on the knowability of claims. In short,
it’s a position on the limits of knowledge. You
might be a skeptic about any knowledge
obtained through the senses, for example,
believing that the senses are too easily fooled.
Or you could be skeptical about the reliability
of memory. Academic skepticism holds that
only those propositions that cannot be doubted,
such as “A=A” or “Not both A and not-A” are
actually known, and that other knowledge
claims are false (that is, it might be true that
the sun is made of hydrogen, but it is false that
we know that it is). Pyrhonnian skeptics, on
the other hand, refuse to assent to either
positive or negative knowledge claims. So they
say neither that we do, nor that we do not,
know that the sun is made of hydrogen, 1+1=2,
etc.
Standpoint
A standpoint is a particular position of a
subject from which the subject experiences and
knows the world. Standpoint theory holds that
having a perspective on the world makes
certain kinds of knowledge accessible or
inaccessible (or perhaps harder to access.) For
example, the ruling class may be blinded to the
specifics of the lives of the oppressed. Thus,
their standpoint rules out (or reduces the access
to) knowledge of the nature of oppression.
Some theorists hold that in most cultures men’s
and women’s standpoints are, due to social
structures, different. Most standpoint theorists
hold that socially-structured, systematic
differences are necessary for the standpoint
differences to occur. Simply being a different
person from someone else isn’t enough to
create inaccessibility of knowledge on this
account. Importantly, if an institution is
dominated by people from a particular
standpoint, that may make certain areas of
knowledge inaccessible. So, potentially, an
institution of white, male scientists might miss
some important piece of information due to
socially-structured limitations on their
perspective.
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Infinite Regress
The infinite regress problem is the problem of
coming to a final resting place for justification.
If I know proposition P1 on the basis of P2,
and I know P2 on the basis of P3, where does it
end? Is it possible to know a proposition
without knowing any other propositions that
support it? There are many forms of this
problem. Here are two examples: suppose I say
I know that the object in front of me is red.
Someone asks how I know that “red” is the
name of that color. I say I learned it in
childhood. How do you know that you learned
it accurately? Everyone seems to be using it the
same way I do. How do you know you haven’t
run into only people who are mistaken? Etc. I
now might enter into an infinite regress of
questions of the form “how did you know
that?” One response is to say that some
knowledge simply doesn’t depend on other
knowledge: this is the foundationalist response.
Others say the regress circles back and forms a
cohesive whole that justifies the knowledge.
This is the coherentist response. Infinitists say
the regress is infinite but that’s not a problem:
an infinite chain is still a justification.
Contextualism
Contextualism is the position that ascriptions
of knowledge (i.e. saying “John knows that his
children are in the yard” or “Keisha knows that
papaya is not poisonous”) are sensitive to the
context of the person attributing the
knowledge. So if Kelly says that she knows
how to get to Demaryius’s house, and in fact
what she believes to be the route to his house is
the route to his house, and she has been there
many times, but the knowledge ascriber knows
that there has been road work in the area and
some roads have been demolished, it is no
longer the case, according to the contextualist,
that Kelly knows how to get to Demaryius’s
house. There is, in these cases, what
epistemologists call “an undefeated defeater,”
that is, a proposition that has not been shown
to be false or non-relevant in this case that
defeats the claim to knowledge. Thus, if Kelly
knows the route, but then Lisa tells her about
the road construction, Kelly ceases to know the
route until such time as she has ascertained that
the road construction did not, in fact, affect the
route, even if, all the time, the route Kelly
believed to be correct was in fact correct.
What gets known
Knowable, Knowables
Some philosophers, including, influentially, Descartes, Kant, and Plato, have pointed out that
some things are knowable, and some things are not. On this view, we can know about a material
object, but we cannot know the object itself. So I might know that a particular table is brown, has
four legs, was owned by John Stuart Mill, etc. But the table itself is made of matter, and matter
cannot enter into mind; only information about matter can do so. On this view, formal properties
are knowable, and abstract ideas are knowable. I can know that all dogs are mammals, I can
know mathematical theorems, general laws of physics, etc. But the matter of the world remains
beyond my grasp, even though I may know its properties. Others candidates for unknowability
include the future, the past, and what it is like to be a bat.