Epistemology: An Introduction and Collection of Resources

This page contains an organized collection of links to beginner friendly videos, podcasts and articles on epistemology. To get started, simply choose a topic from the list below.

What is epistemology?

Epistemology is the study of knowledge. Epistemologists concern themselves with a number of tasks, which we might sort into two categories.

First, we must determine the nature of knowledge; that is, what does it mean to say that someone knows, or fails to know, something? This is a matter of understanding what knowledge is, and how to distinguish between cases in which someone knows something and cases in which someone does not know something. While there is some general agreement about some aspects of this issue, we shall see that this question is much more difficult than one might imagine.

Second, we must determine the extent of human knowledge; that is, how much do we, or can we, know? How can we use our reason, our senses, the testimony of others, and other resources to acquire knowledge? Are there limits to what we can know? For instance, are some things unknowable? Is it possible that we do not know nearly as much as we think we do? Should we have a legitimate worry about skepticism, the view that we do not or cannot know anything at all? – Excerpt from the Internet Encyclopedia of Philosophy article on Epistemology by David A. Truncellito.

Useful Resources:

Foundational Concepts


“Philosophers are interested in a constellation of issues involving the concept of truth. A preliminary issue, although somewhat subsidiary, is to decide what sorts of things can be true. Is truth a property of sentences (which are linguistic entities in some language or other), or is truth a property of propositions (nonlinguistic, abstract and timeless entities)? The principal issue is: What is truth? It is the problem of being clear about what you are saying when you say some claim or other is true. The most important theories of truth are the Correspondence Theory, the Semantic Theory, the Deflationary Theory, the Coherence Theory, and the Pragmatic Theory. They are explained and compared [in the article]. Whichever theory of truth is advanced to settle the principal issue, there are a number of additional issues to be addressed:

  1. Can claims about the future be true now?
  2. Can there be some algorithm for finding truth – some recipe or procedure for deciding, for any claim in the system of, say, arithmetic, whether the claim is true?
  3. Can the predicate “is true” be completely defined in other terms so that it can be eliminated, without loss of meaning, from any context in which it occurs?
  4. To what extent do theories of truth avoid paradox?
  5. Is the goal of scientific research to achieve truth?”

Excerpt from the Internet Encyclopedia of Philosophy article on Truth by Bradley Dowden and Norman Swartz.

Useful Resources:


“Contemporary analytic philosophers of mind generally use the term “belief” to refer to the attitude we have, roughly, whenever we take something to be the case or regard it as true. To believe something, in this sense, needn’t involve actively reflecting on it: Of the vast number of things ordinary adults believe, only a few can be at the fore of the mind at any single time. Nor does the term “belief”, in standard philosophical usage, imply any uncertainty or any extended reflection about the matter in question (as it sometimes does in ordinary English usage). Many of the things we believe, in the relevant sense, are quite mundane: that we have heads, that it’s the 21st century, that a coffee mug is on the desk. Forming beliefs is thus one of the most basic and important features of the mind, and the concept of belief plays a crucial role in both philosophy of mind and epistemology. The “mind-body problem”, for example, so central to philosophy of mind, is in part the question of whether and how a purely physical organism can have beliefs. Much of epistemology revolves around questions about when and how our beliefs are justified or qualify as knowledge.” – Excerpt from the Stanford Encyclopedia of Philosophy article on Belief by Eric Schwitzgebel.

Useful Resources:


We often believe what we are told by our parents, friends, doctors, and news reporters. We often believe what we see, taste, and smell. We hold beliefs about the past, the present, and the future. Do we have a right to hold any of these beliefs? Are any supported by evidence? Should we continue to hold them, or should we discard some? These questions are evaluative. They ask whether our beliefs meet a standard that renders them fitting, right, or reasonable for us to hold. One prominent standard is epistemic justification.

Very generally, justification is the right standing of an action, person, or attitude with respect to some standard of evaluation. For example, a person’s actions might be justified under the law, or a person might be justified before God.

Epistemic justification (from episteme, the Greek word for knowledge) is the right standing of a person’s beliefs with respect to knowledge, though there is some disagreement about what that means precisely. – Excerpt from the Internet Encyclopedia of Philosophy article on Epistemic Justification by Jamie Carlin Watson.

Useful Resources:

Sources of Knowledge


The question of how our perceptual beliefs are justified or known can be approached by first considering the question of whether they are justified or known. A prominent skeptical argument is designed to show that our perceptual beliefs are not justified. Versions of this argument (or cluster of arguments) appear in René Descartes’s Meditations, Augustine’s Against the Academicians, and several of the ancient and modern skeptics (e.g., Sextus Empiricus, Michel de Montaigne). The argument introduces some type of skeptical scenario, in which things perceptually appear to us just as things normally do, but in which the beliefs that we would naturally form are radically false. To take some standard examples: differences in the sense organs and/or situation of the perceiver might make her experience as cold things that we would experience as hot, or experience as bitter things that we would experience as sweet; a person might mistake a vivid dream for waking life; or a brain in a vat might have its sensory cortices stimulated in such a way that it has the very same perceptual experiences that I am currently having, etc….

The skeptical scenarios (dreaming, brains in vats, differently situated sense organs, etc.) call our attention to a crucial distinction between appearance and reality: how things perceptually appear is not necessarily how things really are; things could appear the same though really be different, and they could appear to be some other, incompatible way and really be the same. – Excerpt from the Stanford Encyclopedia of Philosophy article on Epistemological Problems of Perception by Jack Lyons.

Useful Resources:


“We learn a lot. Friends tell us about their lives. Books tell us about the past. We see the world. We reason and we reflect on our mental lives. As a result we come to know and to form justified beliefs about a range of topics. We also seem to keep these beliefs. How? The natural answer is: by memory. It is not too hard to understand that memory allows us to retain information. It is harder to understand exactly how memory allows us to retain knowledge and reasons for our beliefs. Learning is largely a matter of acquiring reasons for changing views. But how do we keep reasons for the views we keep? The epistemology of memory concerns memory’s role in our having knowledge and justification. This branch of epistemology, unlike nearly all other branches, addresses our having knowledge and justification over time.” – Excerpt from the Internet Encyclopedia of Philosophy article on Epistemology of Memory by Matthew Frise.

Useful Resources:


“Consider two lives. Helen Keller was born blind and deaf, but her access to the written word enabled her to succeed as a writer and activist. Peter the Wild Boy, discovered near Hanover, Germany in 1719, possessed sight and hearing, but was innocent of language. He left the world as innocent as he came. “Without artifice, particularly the shared human artifice of speech, an unmeaning silence traps Peter in an unvarying bestiality” (Newton 2002, 44. Emphasis mine).

The stark comparison illustrates the degree of our dependence on the word of others. Without the ability to give and receive testimony, we cannot transcend the limitations of our individual faculties to borrow from the thoughts, observations, and experiences of others. The kind of knowledge that separates human beings from the rest of the animal world disappears. While a deficiency in one’s sensory faculties can perhaps be compensated for, inability to draw from the knowledge of others forecloses all possibility of higher knowledge.” – Excerpt from the 1000 Word Philosophy article: Take My Word for It: On Testimony by Spenser Case.

Useful Resources:

The Problem of Skepticism

“Even well-grounded beliefs can be mistaken. We can be deceived by our senses. We are fallible in perceptual matters, as in our memories, in our reasoning, and in other respects. One might now wonder, as skeptics do, whether we know even that it is improbable that our senses are now deceiving us. One might also wonder whether, when we take ourselves to see green grass, we are even justified in our belief that no such mistake has occurred. Suppose that I am in an unfamiliar park. I might not know or even justifiedly believe that artificial grass has not replaced the natural grass I take to be before me. (I may have heard of such substitutions and may have no good reason to believe this has not happened, though I do not consider the matter.) Am I justified in believing that there is green grass before me? Suppose that I am not justified in believing there is green grass before me. If not, how can I be justified in believing what appear to be far less obvious truths, such as that my home is secure against the elements, my car safe to drive, and my food free of poison? And how can I know the many things I need to know in life, such as that my family and friends are trustworthy, that I can control my behavior and thus partly determine my future, and that the world we live in at least approximates the structured reality portrayed by common sense and science?” – Excerpt from Epistemology: A Contemporary Introduction to the Theory of Knowledge by Robert Audi.

Useful Resources:


It is obvious that if we are asked why we believe it the sun will rise to-morrow, we shall naturally answer, ‘Because it always has risen every day’. We have a firm belief that it will rise in the future, because it has risen in the past….

Do any number of cases of a law being fulfilled in the past afford evidence that it will be fulfilled in the future? If not, it becomes plain that we have no ground whatever for expecting the sun to rise to-morrow, or for expecting the bread we shall eat at our next meal not to poison us, or for any of the other scarcely conscious expectations that control our daily lives….

And this kind of association is not confined to men; in animals also it is very strong. A horse which has been often driven along a certain road resists the attempt to drive him in a different direction. Domestic animals expect food when they see the person who feeds them. We know that all these rather crude expectations of uniformity are liable to be misleading. The man who has fed the chicken every day throughout its life at last wrings its neck instead, showing that more refined views as to the uniformity of nature would have been useful to the chicken.

But in spite of the misleadingness of such expectations, they nevertheless exist. The mere fact that something has happened a certain number of times causes animals and men to expect that it will happen again. Thus our instincts certainly cause us to believe the sun will rise to-morrow, but we may be in no better a position than the chicken which unexpectedly has its neck wrung. – Excerpt from The Problems of Philosophy by Bertrand Russell.

Useful Resources:

Further Reading

If you have never studied epistemology before, the following books are a good place to start:

Primary Sources:

Secondary Sources:

Miscellaneous Resources

1000 Word Philosophy

Wireless Philosophy

Philosophy Bites

Stanford Encyclopedia of Philosophy

Internet Encyclopedia of Philosophy

If you’d like to learn more about Epistemology, check out:

The Daily Idea collects and organizes the best philosophy resources from across the internet to help make learning about philosophy as easy as possible. You can find an organized collection of introductory readings and free philosophy resources here. Or get started below by signing up for a free philosophy quote delivered to your inbox each day!