Epistemology

A Contemporary Introduction to the Theory of Knowledge

Robert Audi

• Publisher: Routledge
• Year: 2010
• ISBN:
  9781136934469
• Edition: 3
• Topic: Philosophy
• Subtopic: Epistemology in Philosophy

Epistemology, or "the theory of knowledge, " is concerned with how we know what we know, what justifies us in believing what we believe, and what standards of evidence we should use in seeking truths about the world and human experience. This comprehensive introduction to the field of epistemology explains the concepts and theories central to understanding knowledge. Along with covering the traditional topics of the discipline in detail, Epistemology explores emerging areas of research. The third edition features new sections on such topics as the nature of intuition, the skeptical challenge of rational disagreement, and "the value problem" – the range of questions concerning why knowledge and justified true belief have value beyond that of merely true belief. Updated and expanded, Epistemology remains a superb introduction to one of the most fundamental fields of philosophy.

Special features of the third edition of Epistemology include:

• a comprehensive survey of basic concepts, major theories, and emerging research in the field
• enhanced treatment of key topics such as contextualism, perception (including perceptual content), scientific hypotheses, self-evidence and the a priori, testimony, understanding, and virtue epistemology
• expanded discussion of the relation between epistemology and related fields, especially philosophy of mind, philosophy of science, and ethics
• increased clarity and ease of understanding for an undergraduate audience
• an updated list of key literature and annotated bibliography.

Part One

Sources of justification, knowledge, and truth

1 Perception

Sensing, believing, and knowing

As I look at the green field before me, I might believe not only that there is a green field there but also that I see one. And I do see one. I visually perceive it. Both beliefs, the belief that there is a green field there, and the self-referential belief that I see one, are grounded, causally, justificationally, and epistemically, in my perceptual experience. They are produced by that experience, justified by it, and constitute knowledge in virtue of it.

The same sort of thing holds for the other senses. Consider touch. I not only believe, through touch (as well as sight), that there is a glass here, I also feel its cold surface. Both beliefs—that there is a glass here and that it is cold—are grounded in my tactual experience. I could believe these things on the basis of someone’s testimony. My beliefs would then have a quite different status. For instance, my belief that there is a glass here would not be a perceptual belief, but only a belief about a perceptible, that is, a perceivable object, the kind of thing that can be seen, touched, heard, smelled, or tasted. Through testimony we have beliefs about perceptibles we have never seen or experienced in any way.

My concern is not with the hodgepodge of beliefs that are simply about perceptibles, but with perception and perceptual beliefs. Perceptual beliefs are not simply beliefs about perceptibles; they are beliefs grounded in perception. We classify beliefs as perceptual by the nature of their roots, not by the color of their foliage; by their grounds, not their type of content. Those roots may be visual, auditory, and so forth for each perceptual mode. But vision and visual beliefs are an excellent basis for discussing perception, and I will concentrate on them and mention the other senses only when it adds clarity.

Perception is a source of knowledge and justification mainly by virtue of yielding beliefs that constitute knowledge or are justified. But we cannot hope to understand perceptual knowledge and justification simply by exploring those beliefs. We must also understand what perception is and how it yields beliefs. We can then begin to understand how it yields knowledge and justification or—sometimes—fails to yield them.

The elements and basic kinds of perception

There are apparently at least four elements in perception: (1) the perceiver, me; (2) the object, the field I see; (3) the sensory experience, say my visual experience of colors and shapes; and (4) the relation between the object and the subject, commonly taken to be a causal relation by which the object produces the sensory experience in the perceiver. To see the field is apparently to have a certain sensory experience as a result of the impact of the field on our vision.

Some accounts of perception add to the four items on this list; others subtract from it. To understand perception we must consider both kinds of account and how these elements are to be conceived in relation to one another. But first, it is essential to explore examples of perception.

There are several quite different ways to speak of perception. Each corresponds to a different way of perceptually responding to experience. We often speak simply of what people perceive, for instance see. We also speak of what they perceive the object to be, and we commonly talk of facts they know through perception, such as that the grass is long. Visual perception most readily illustrates this, so let us start there.

I see, hence perceive, the green field. Second, speaking in a less familiar way, I see it to be rectangular. Thus, I might say that I know it looks irregular from the nearby hill, but from the air you can see it to be perfectly rectangular. Third, I see that it is rectangular. Perception is common to all three cases. Seeing, which is a paradigm perception, is central in each.

The first case is one of simple perception, perception taken by itself (here, visual perception). I see the field, and this experience is the visual parallel of hearing a bird (an auditory experience), touching a glass (a tactual experience), smelling roses (an olfactory experience), and tasting mint (a gustatory experience). If the first case is simply perceiving of some object, the second is a case of perceiving to be, as it is seeing something to be so: I do not just see the field, as when I drive by at high speed and do not even realize what is in my peripheral vision; rather, I see the field to be rectangular. The third case is one of perceiving that; it is seeing that a particular thing is so, namely that the field is rectangular.

These cases represent three kinds, or modes, of perception. Perception of the simplest kind (or in the simplest mode), such as seeing, occurs in all three; but, especially because of their relation to knowledge and justified belief, they are significantly different. We can best understand these three kinds (or modes) of perception if we first focus on their relation to belief.

Perceptual belief

The last two cases—perceiving that, and perceiving to be—are different from the first—perceiving of—in implying corresponding kinds of beliefs: seeing that the field is rectangular implies believing that it is, and seeing it to be green implies believing it to be green. If we consider how both kinds of beliefs—beliefs that something is so and beliefs of (hence about) something—are related to perception, we can begin to understand how perception occurs in all three cases, the simple and the more complex. In my second and third examples of perception, visual perception (seeing) issues in beliefs that are grounded in seeing and can thereby constitute visual knowledge, such as knowing that the field is green.¹

In our example of simple perception, my just seeing the field provides a basis for both kinds of beliefs. It does this even if, because my mind is entirely occupied with what I am hearing on the radio as I glance over the field, no belief about the field actually arises in me. The visual experience is, in this instance, like a foundation that has nothing built on it but is ready to support a structure. If, for example, someone were to ask if the field has shrubbery, then given the lilacs prominent in one place, I might immediately form the belief that it does and assent. This belief is visually grounded; it comes from my seeing the field though it did not initially come with it. When visual experiences do produce beliefs, as they usually do, what kinds of beliefs are these, and how are they specifically perceptual?

Many of my beliefs arising through perception correspond to perception that, say to seeing that the lilacs are blooming. I believe that the field is lighter green toward its borders, that it is rectangular in shape, and that it has many ruts. But I may also have various beliefs about it that are of the second kind: they correspond to perception to be, for instance to seeing something to be a certain color. Thus, I believe the field to be green, to be rectangular, and so on. The difference between these two kinds of belief is significant. As we shall shortly see, it corresponds first of all to two distinct ways in which we are related to the objects we perceive and, second, to two different ways of assessing the truth of what, on the basis of our perceptions, we believe.

The first kind of belief just described is the kind people usually think of when they consider beliefs: it is called propositional, as it is generally considered a case of believing a proposition—say, that the field is rectangular. The belief is thus true or false depending on whether the proposition in question—here that the field is rectangular—is true or false. In holding the belief, moreover, in some way I think of what I see as a field which is rectangular: in believing that the field is rectangular, I conceive what I take to be rectangular as a field.

The second kind of belief might be called objectual: it is a belief regarding an object, say the field, with which the belief is actually connected. This is an object of (or about) which I believe something, say that it is rectangular. If I believe the field to be rectangular, there really is such an object, and I have a certain relation to it. A special feature of this relation is that there is no particular proposition I must believe about the field. To see that there is no particular proposition, notice that in holding this objectual belief I need not think of what I see as a field. I might mistakenly take it to be (for instance) a lawn or a grasslike artificial turf, yet still believe it to be rectangular. I might think of it just in terms of what I believe it to be and not in terms of anything else.

Thus, although there is some property I must take the field to have—corresponding to what I believe it to be—there is no other particular way I must think of it. With objectual belief, then, there is no particular notion, no specific conceptual “handle,” that must yield the subject of any proposition I believe about the object: I do not have to believe that the field is green, that the grass is green, or any such thing. Perception leaves us vast latitude as to what we learn from it. People differ greatly in the beliefs they form about the very same things they see.²

The concept of objectual perception, then, is very permissive about what one believes about the object perceived. This is one reason why it leaves so much space for imagination and learning—a space often filled by the formation of propositional beliefs, each capturing a different aspect of what is perceived, say that the field is richly green, that it is windblown, and that it ends at a treeline.

A different example may bring these points out further. After seeing a distant flare and coming to believe, of something blurry and far away, that it glowed, one might ask, ‘What on Earth was it that glowed?’ Before we can believe the proposition that a flare glowed, we may have to think about where we are, the movement and fading of the glow, and so forth. The objectual belief is a guide by which we may arrive at propositional beliefs and propositional knowledge.

Perception, conception, and belief

The same kind of example can be used to illustrate how belief depends on our conceptual resources in a way that perception does not. Suppose I had grown up in the desert and somehow failed to acquire the concept of a field. I could nonetheless see the green field, and from a purely visual point of view it might look the same to me as it does now. I could also believe, regarding the field I see—and perhaps conceive as sand artificially covered with something green—that it is rectangular. But I could not believe that the field is rectangular. This propositional belief as it were portrays what I see as a field in a way that requires my having a concept of one.

There is a connection here between thought and language (or at least conceptualization). If I believe (think) that the field is rectangular, or even simply have the thought that it is, I should be able to say that it is and to know what I am talking about. But if I had no concept of a field, then in saying this I would not know what I am talking about.³ Similarly, a two year old, say, Susie, who has no notion of a tachistoscope, can, upon seeing one and hearing its fan, believe it to be making noise; but she cannot believe specifically that the tachistoscope is making noise. Her propositional belief, if any, would be, say, that the thing on the table is making noise. Since this is true, what she believes is true and she may know this truth, but she need not know much about the object this truth concerns: in a way, she does not know what it is she has this true belief about.

The general lesson here is important. A basic mode of learning about objects is to find out truths about them in this elementary way: we get a handle on them through perceptually discriminating some of their properties; we form objectual (and other) beliefs about them from different perspectives; and (often) we finally reach an adequate concept of what they are. From the properties I believe the flare in the distance to have, I finally figure out that it is a flare that has them. This suggests that there is at least one respect in which our knowledge of (perceptible) properties is more basic than our knowledge of the substances that have them; but whether that is so is a question I cannot pursue here.

Unlike propositional beliefs, objectual beliefs have a significant degree of indefiniteness in virtue of which it can be misleading simply to call them true or false; they are accurate or inaccurate, depending on whether what one believes of the object (such as that it is rectangular) is or is not true of it. Recall Susie. If she attributes noise-making to the tachistoscope, she truly believes, of it, that it is making noise. She is, then, right about it. But this holds even if she has no specific concept of what it is that is making the noise. If we say unqualifiedly that her belief about it is true, we invite the question ‘What belief?’ and the expectation that the answer will specify a particular proposition, say that the tachistoscope is making noise. But it need not, and we might be unable to find any proposition that she does believe about it. She can be right about something without knowing or even having any conception of what kind of thing it is that she is right about.

Knowledge is often partial in this way. Still, once we get the kind of epistemic handle on something that objectual belief can provide, we can usually use that to learn more about it.⁴ Suppose I see a dog’s tail projecting from under a bed and do not recognize it as such. If I believe it to be a slender furry thing, I have a place to start in finding out what else it is. I will, moreover, be disposed to form such beliefs as that there is a slender furry thing there. I will also have justification for them. But I need not form them, particularly if my attention quickly turns elsewhere.

Propositional and objectual perception

Corresponding to the two kinds of beliefs I have described are two ways of talking about perception. I see that the field is rectangular. This is (visual) propositional perception: perceiving that. I also see it to be rectangular. This is (visual) objectual perception: perceiving to be. The same distinction apparently applies to hearing and touch. Perhaps, for example, I can hear that a piano is out of tune by hearing its sour notes, as opposed to hearing the tuner say it needs tuning. As for taste and smell, we speak as if they yielded only simple perception: we talk of smelling mint in the iced tea, but not of smelling that it is minty or smelling it to be minty. Such talk is, however, intelligible on the model of seeing that something is so and seeing it to be so. W...