1. An Introduction to Epistemology PDF

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An Introduction to Epistemology David Alexander

1. What is Epistemology? Here’s a scenario familiar to fans of science fiction. There’s a person, let’s call her Susan, who lives a life strikingly similar to yours. She is around your age and, just like you, has all the experiences of being a student at university. She enjoys taking a range of challenging classes and meeting new people. In her spare time she enjoys jogging around campus. And just like you she has a wealth of memories of her prior experiences, including her upbringing and family life, high school experiences, and formative friendships. You get the gist. But now here’s the twist. Susan is not like you at all. Susan’s apparent reality is completely illusory. Unbeknownst to her, Susan has been hooked up to a digital simulation of reality for the entirety of her life. What she experiences is a sophisticated virtual reality fed directly into her brain –– something like the fanciest video game imaginable. When Susan thinks she is jogging around campus admiring the cherry blossoms, there are no trees — just her and the deceptive simulation. And when Susan thinks she is at a party, meeting new people, sadly she is all alone, interacting only with a program that produces mere illusions of people, bereft of conscious thoughts and feelings. (Different versions of this kind of scenario have been explored in movies like The Matrix, Existenz, and Vanilla Sky.) Now a philosophical question: how do you know that you are not in a scenario like Susan’s? Put another way: do you have any good reason for thinking that you are not in a simulation? No doubt you believe that you are not in a simulation — probably with a great degree of confidence. But what reason do you have for such confidence? How could you defend this

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strongly held belief? This challenge is quite demanding. Indeed, you might be at a loss as to how it could be met. After all, you and Susan have very similar experiences. Any experiences of yours that you could point to as proof of your not being in a simulation are matched by similar, but illusory experiences that Susan has. If so, how can you claim to know that unlike Susan, you are not in simulation? These are epistemological questions. Epistemology is the study of knowledge and rational belief. (“Episteme” is the Greek word for knowledge.) Epistemologists seek to understand what it takes to know or rationally believe something. They also seek to understand their extent: how much can we know or rationally believe? Is it possible to know that we are not in a simulation, like Susan? What about whether God exists or not –– is this something that we can have knowledge of, or is this beyond the limits of what we can know? What about the experiences of others –– can we truly know what others experience when they taste chocolate, feel depressed or elated? Epistemologists seek to understand the nature of knowledge and rational belief in order to answer these kinds of questions. Hopefully this teaser not only gives you a sense as to what epistemology involves, but also piques your interest. To fill this in a bit more in what remains of this introduction I will do two things. First, I will introduce you to two basic epistemological concepts that will frame our discussion. Second, using those concepts I will give you additional examples of epistemological problems.

2. Knowledge and Rational Belief Knowledge and rational belief are the two central concepts of epistemology. Most philosophers regard them as related. To appreciate why, let’s begin with knowledge.

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There are different kinds of knowledge. One can know a thing, in the sense of being familiar with it, such as knowing a person or a city. One can know how to do something, a kind of ability, such as how to ride a bike or bake a cake. Epistemologists are most concerned with what it takes to know some fact, such as knowing that the capitol of Iowa is Des Moines. Or to paraphrase, we are interested in what is involved in knowing that a claim or proposition is true. This kind of knowledge is commonly referred to as propositional knowledge. This kind of knowledge is of particular interest since we all, at some level, care about truth, or accurate accounts of what the facts are. After all, we all have to figure out how to live our lives and act in this confusing world based on our beliefs about how things are. And when we are mistaken the consequences can be disastrous. So what does it take to know a proposition? Epistemologists generally agree that knowledge requires belief. To know that it is raining out, you have to believe that it is raining out. Perhaps this point strikes you as obvious. Nevertheless, it’s helpful to clarify it with some observations about the nature of belief. What is a belief? Belief is taking some proposition to be true. Belief thus contrasts with disbelief — which involves taking a proposition to be false rather than true. It also contrasts with withheld belief or suspended judgment — which involves being undecided about whether a proposition is true or instead false. Because believing, disbelieving, and withholding belief all involve attitudes towards propositions, they are called “propositional attitudes.” So the idea that knowledge requires belief can be thought of this way. When it comes to any proposition, you can believe it, disbelieve it, or withhold belief in it. But only believing a proposition is compatible with knowing it. After all, you can’t know that it is raining if you disbelieve that it is raining — that is, if you think it is false that it is raining. Similarly, you can’t know that it is raining if you withhold belief and have no opinion on the matter. If so, to know a proposition you better believe it.

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However, while belief is a necessary condition of knowledge, it is not sufficient. That is, some beliefs do not qualify as knowledge. Suppose that a student taking an exam believes very confidently that the answer to the question “What year did the French Revolution occur?” is 1779. This is a mistake: the correct date is 1789. We would not describe the student as knowing the date of the French Revolution — no matter how confident he or she is. That’s because for a belief to qualify as knowledge, the proposition one believes must be true, not false. Otherwise put, to qualify as knowledge your belief must be right — it cannot be mistaken. This is part of the value of knowing: being right. If you could know something false, knowledge would not be quite so valuable. While true belief is a necessary condition of knowledge, it is not sufficient. That is, some true beliefs do not qualify as knowledge. Suppose that you have been studying hard all day long in the windowless basement of Parks Library. You are exhausted from all your hard work and in addition, starving. This makes you cranky. Because of your bad mood you cannot help but believe that it is raining out and that lacking an umbrella, you are going to get soaked. Now, suppose that you have no good reason to believe this at all: you haven’t looked out a window in hours, you haven’t looked at a weather report, and buried deep in the basement of the library you haven’t even seen anyone come in from outside to check whether they are wet, or shaking off umbrellas etc. Your belief is entirely motivated by your crankiness. But here’s the thing: it just so happens that your belief is indeed correct. It is pouring out and you will get soaked. In other words, you have a true belief. But do you know that it is raining out? Surely not. Although your belief is accurate, it still falls short of knowledge. So you’ve got a true belief, but not knowledge. What’s missing? What necessary condition of knowledge have you not satisfied? This is more controversial. However, the explanation preferred by most epistemologists is that your belief does not qualify as knowledge because it is not rational, or justified. (I will be using these two terms interchangeably.) Your belief

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that it is raining is not grounded on, or motivated by appropriate considerations, but is instead based on your crankiness, which has no connection to the weather. If you had believed it was raining because you looked out the window and saw that it was raining, then your belief would be rational. If you had believed it was raining because you checked a trustworthy weather app on your phone, then your belief would be rational. But as it stands your true belief fails to be knowledge because it is motivated by irrelevant emotional matters and is not rational. So knowledge requires having true belief that is also rational, or justified. But what is it for a belief to be rational? Of the issues we have touched on so far, this is by far the most contentious. There are many debates about the nature of rational belief, some of which you will encounter in this module. However, epistemologists are in broad agreement regarding one sufficient condition of rational belief. Namely: if a belief is based on strong reasons or evidence that make it highly likely that the belief is true, then it is rational. So the idea is that good evidence, or strong reasons in favor of the truth of a proposition can make believing it rational. Recall our example of you studying in the basement of the library and coming to believe that it is raining simply because you are cranky. If you instead came to believe that it is raining because you looked out the window and saw it raining, then your belief would be rational. It would be supported by good reasons or evidence: your observations. I know what you’re going to ask next: but what counts as good reasons or evidence? I’m not going to try to answer that here. The reason is simple: this is one of the issues that epistemologists aspire to figure out. It’s an issue we will be wrestling with in this course. For present purposes two points can be made. First, we all have some kind of intuitive grasp as to what counts as good reasons, or evidence. For example, when it comes to believing that it is raining out, we would all normally agree that an observation of the rain is a very good reason for belief, whereas being hungry is not. Good reasons or evidence make it very likely that what you believe is true, whereas

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bad reasons do not. Second, for our purposes I will be treating “reasons” and “evidence” as roughly equivalent. Why two words? Well, it can often be useful to paraphrase one idea in several different ways. The rationality condition on knowledge is arguably the most significant of the conditions we have discussed. It’s this condition that makes the acquisition of knowledge not only a challenge, but also a significant intellectual achievement. To illustrate, consider belief in the existence of God. Having a belief as to whether God exists is not hard. Lots of people believe that God exists, and lots believe that God does not exist. Merely having an opinion is not hard. And if you think about it, one of these camps must be right — either God exists or does not — which means that plenty of people have a true belief about whether God exists. But that doesn’t mean that lots of people have a rational belief or knowledge about whether God exists. Indeed, this seems unlikely. After all, the existence of God is a classic example of an extremely challenging philosophical issue. It has been debated for centuries and yet to this day people still passionately disagree. If so, although one of the camps must be right about whether God exists, it’s an open question whether anybody really has knowledge about the matter. There’s an important moral here. In general while it’s easy to believe, and with a bit of luck, easy to believe truly, it is much harder to know. And that’s partly because it can take quite a bit of work to acquire strong reasons for one’s beliefs. What it takes to have such reasons will be the focus of this module. Time to summarize. Propositional knowledge is knowledge of true claims, knowledge of what the facts are. This kind of knowledge has several necessary conditions. Knowledge requires belief. It also requires that what one believes be true. Most significantly, knowledge requires rational or justified belief, and that requirement can be satisfied by having strong reasons for belief, or supporting evidence.

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If you’ve been following this overview carefully, two advanced questions might have come to mind. Although you won’t be expected to understand them for this module, I mention them briefly for those who are curious. First, granting that a rational true belief is necessary for knowledge, is it the case that it is also sufficient for knowledge? The answer is no. Epistemologists generally agree that there are additional conditions on knowledge. I won’t explain why here, since these additional conditions will not be relevant to the present module, which will focus on what it takes to have good reasons for our beliefs. Second, is it possible to have a rational or justified belief without having any reasons or evidence supporting what one believes? If you like, can one have “groundless knowledge” not backed up by any reasons or evidence? The philosophical jury’s still out on this one, and if you want to learn more about that debate you will have to take an advanced class in epistemology. For present purposes we need not resolve it, as our focus will be on what it takes to have good reasons for believing. And that is something that is interesting regardless of whether there is groundless knowledge.

3. Epistemological Questions This brief introduction to knowledge and rational belief allows us to appreciate the kinds of issues epistemologists hope to address. Here I will mention two. i. What are the sources of knowledge and rational belief? It seems that a great deal of our knowledge comes from the senses. Or put in terms of rationality: in normal circumstances our senses provide us with good reason to believe various claims about the world. What are some of the other sources of knowledge and rational belief? Some of the big candidates include: memory, introspection (the way in which one monitors the state of one’s own mind), the testimony of others, as well as our ability to reason from the information provided by these sources.

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When it comes to any of these sources we can ask whether they really do provide us with good reason to believe, and if so how. Consider testimony. Does the fact that someone tells you something give you any reason whatsoever for believing it? It’s not clear. We all know that people can assert false things, either because they are lying or sincere but mistaken. Given this, you might think that we should never “blindly” trust what another says. On the other hand, human beings are profoundly social creatures who seem to extensively rely on a blind trust in others. For example, most of us are perfectly comfortable trusting the directions given to us by a random stranger that we meet on the street. Is this reasonable or not? Another classic question about sources is whether the mind is capable of discovering truths about the world all on its own, without relying on any information provided by the senses. Can one come to discover certain truths just through the operation of pure thought? Such knowledge is called “a priori” knowledge. Throughout the history of the discipline, many philosophers have held that a priori knowledge is possible, and have cited mathematics as a clear example. A smart mathematician can start with obvious, self-evident axioms, and discover their surprising consequences simply through careful thinking. No observations need to made, no testimony relied on. But how is this remarkable achievement possible? What kind of evidence or reason can the mind provide for believing claims, all on its own? ii. Skepticism. Skeptics argue that we know a lot less than we assume — that many of our beliefs are not rational, but rather dogmatically held. This introduction opened with an illustration of skeptical reasoning. Skeptics will claim that we dogmatically trust that our senses give us a correct picture of the world and without any good reason dismiss skeptical alternatives like the possibility of our being in a simulation.

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Another classical skeptical argument is from disagreement. Skeptics note how often we disagree with one another on matters of great importance: morality, religion, politics, and philosophy itself. This disagreement, they suggest, indicates that we don’t have very compelling reasons on behalf of our positions. After all, if we had such decisive reasons, we should be able to easily persuade those who disagree, and there should be a tendency for us all to converge on the one correct view. But of course this almost never happens and instead people remain entrenched in their position. These are just two examples of skeptical arguments from a rich tradition — there are many more. Most epistemologists are not skeptics and seek to respond to these skeptical arguments, vindicating the commonsense position that we know a great deal. But the challenge presented by the skeptical tradition cannot be overstated.

4. Conclusion Hopefully this introduction has given you a sense for what epistemology is about. There’s more to come. In closing, let us review the key concepts and working assumptions that will frame our discussion as we move forward. The key concepts we have touched on are: • Propositional knowledge • Three propositional attitudes: belief, disbelief, withheld belief • Three necessary conditions on knowledge: Belief Truth Rationality or justification • Good evidence or reasons And the three crucial working assumptions are:

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• Propositional knowledge consists of knowing true propositions, or facts. • To know, one must have a rational (or justified) true belief. • One has a rational, or justified belief if one’s belief is based on good evidence or strong reasons that suggest that one’s belief is true. As we move forward, our focus will be on what it takes to have good reasons or evidence for our beliefs. What counts as good reasons? Do we ever have sufficient evidence to believe anything? We will consider these questions and more as we work through selections from Rene Descartes’s Meditations on First Philosophy.

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