An Introduction to the Theory of Knowledge

Dan O'Brien

• Publisher: Polity
• Year: 2016
• ISBN:
  9781509512409
• Edition: 2
• Topic: Philosophy
• Subtopic: Epistemology in Philosophy

An Introduction to the Theory of Knowledge, 2ndEdition guides the reader through the key issues and debates in contemporary epistemology. Lucid, comprehensive and accessible, it is an ideal textbook for students who are new to the subject and for university undergraduates. The book is divided into five parts. Part I discusses the concept of knowledge and distinguishes between different types of knowledge. Part II surveys the sources of knowledge, considering both a priori and a posteriori knowledge. Parts III and IV provide an in-depth discussion of justification and scepticism. The final part of the book examines our alleged knowledge of the past, other minds, morality and God. In this extensively revised second edition there are expanded sections on epistemic luck, social epistemology and contextualism, and there are new sections on the contemporary debates concerning the lottery paradox, pragmatic encroachment, peer disagreement, safety, sensitivity and virtue epistemology. Engaging examples are used throughout the book, many taken from literature and the cinema. Complex issues, such as those concerning the private language argument, non-conceptual content, and the new riddle of induction, are explained in a clear and accessible way. This textbook is an invaluable guide to contemporary epistemology.

PART I
INTRODUCTION TO KNOWLEDGE

1
The Theory of Knowledge

1 Epistemology

The Theory of Knowledge asks certain very general and very fundamental questions about knowers and knowledge. What is it to know? How is knowledge distinct from mere belief? Is knowledge possible? The Theory of Knowledge is also referred to as epistemology, from the Greek word for knowledge, ‘episteme’. Epistemology has a long history: in working through this book you will become engaged in a dialogue that has gone on for well over two thousand years. In the next chapter we shall begin our analysis of knowledge by turning to Plato (c. 428–347 BCE), and throughout our investigations we shall look at what important thinkers of the past have said: René Descartes (1596–1650) and David Hume (1711–1776) will have a high profile. Epistemology remains an area of vibrant research, and many of the positions and theories at which we shall look have emerged in the last few decades. This continued interest in epistemology is a reflection of the immense importance of knowledge in our lives. First, it is instrumentally useful: with scientific knowledge, for example, we hope to explain, control and predict the behaviour of the natural world. Second, even where knowledge has no practical use, we have the attitude that it is still something desirable to obtain. It is good in itself. After a criminal in the film Dirty Harry (1971) has given up his gun to Inspector Harry Callahan, he wants to know whether Harry had any bullets left in his gun or whether he was bluffing – ‘I gots to know’. This information will be of no use to him – he is now arrested, regardless – but it is nevertheless knowledge that he seeks.

Epistemology and Metaphysics are the two central topics of Philosophy. The former concerns the nature and possibility of knowledge; the latter concerns the nature of what exists. Metaphysical questions include: Are there things that are non-physical? Are there any other minds in existence apart from your own? And does God exist? We shall see that all of these issues intersect with our epistemological investigations. Along with epistemology, then, we shall be studying some metaphysics. Epistemology is also intimately related to other areas of philosophy, and we shall be introduced to issues in the philosophy of mind, the philosophy of religion, and ethics.

2 The Structure of the Book

2.1 Part I: Introduction to knowledge

To study any topic, we must first have a preliminary idea of the kind of things we are going to investigate. Biologists must know what they are talking about when referring to ‘armadillos’, ‘cells’ or ‘mitochondria’. Similarly the epistemologist: she, however, is concerned with such notions as knowledge, justification and belief, and with how they are related. Here and in the next chapter we shall start to look at just what we mean by ‘knowledge’, and in the rest of the book we shall investigate the nature of knowledge and the problems associated with it. Our primary concern will be with factual knowledge. I can know that Glasgow is in Scotland, that it was Descartes who wrote the Meditations, and that Bernice bobs her hair. Such knowledge is sometimes called ‘knowledge that’ or ‘propositional knowledge’; ‘propositional’ because it’s expressed in terms of the knowledge I have of certain true propositions or thoughts: I know that the proposition Glasgow is in Scotland is true. As well as with the words, ‘knows that’, factual knowledge is also expressed using such locutions as ‘knows why’, ‘knows where’, ‘knows when’, ‘knows whether’, ‘knows who’, and ‘knows what’. Such ways of speaking indicate that you know certain facts: in knowing where I left my keys, I know that they are in the coffee shop; in knowing when the programme starts, I know that it starts at 9 o’clock. Such knowledge can also be expressed without using the word ‘know’ at all. I could say that ‘My keys are in the café over there’ or that ‘The programme starts now’. These statements are nevertheless expressions of factual knowledge.

There are other kinds of knowledge apart from factual knowledge. One is know-how: I know how to ride a bike and how to make a Tequila Sunrise cocktail. This is sometimes called ‘ability knowledge’. We need to be a little careful here since I can have such knowledge without actually possessing the relevant ability. Practical constraints may prevent me from exercising a certain ability even though I know how it should be done: I may have temporarily lost my sense of balance and thus cannot ride my bike, or I may have run out of grenadine and so right now I cannot make a Tequila Sunrise. Knowing how to do certain things can involve the possession of factual knowledge. If I know how to play snooker, I must know that the blue ball has a points value of five, and that a red ball must be potted before I can pot a colour. However, in order to have other abilities, I do not require knowledge of any facts. I know how to perform such basic actions as walking, swimming and speaking without knowing that I move my body or mouth in a particular way: I can have know-how without the relevant propositional knowledge.

A third type of knowledge is knowledge by acquaintance. I know a certain person because I’ve met her; I know that melody because I’ve heard it before; and I know Yosemite National Park because I’ve been there. I can have such knowledge without knowing any facts about these things. I can, for example, know that melody without knowing what it is called, or without having any further beliefs about it at all; I just know it. Other languages use a different word to talk about this kind of knowledge. In French, ‘savoir’ is to have factual knowledge, whereas ‘connaître’ is to have knowledge by acquaintance. In German the two relevant verbs are ‘wissen’ and ‘kennen’. Knowledge, then, can involve acquaintance; various practical, intellectual and physical skills; and the knowledge of certain truths or facts. This book is mainly concerned with the latter kind of knowledge.

2.2 Part II: Sources of knowledge

We acquire factual knowledge in various ways. I can come to know certain truths just by thinking about the issue in question. I know that there are no triangles with as many sides as a square. I do not have to draw lots of triangles and squares to know that this is so; I simply have to use my powers of reasoning. Such knowledge is called a priori (meaning before experience) and it will be the subject of chapter 3. The main focus of the book, however, will be knowledge that is acquired through experience, or what is called empirical or a posteriori knowledge (meaning after experience). There are two sources of such knowledge: it is acquired either through perceiving the world for ourselves (chapter 4), or by listening to what others have to say or reading what they have written (chapter 5).

2.3 Part III: Justification

Knowledge has traditionally been seen as involving justification: if I am to have knowledge, I must have true beliefs and I must have good reason or justification for holding them. In part III we shall focus on this key notion of justification. First, though, we must be careful to distinguish the epistemic sense of ‘justification’ from certain other uses of the term. The basic idea – and one that we shall go on to develop (and question) – is that my beliefs are epistemically justified if I have good reason to think that they are true.

The basic role of justification is that of a means to truth … If epistemic justification were not conducive to truth …, if finding epistemically justified beliefs did not substantially increase the likelihood of finding true ones, then epistemic justification would be irrelevant to our main cognitive goal and of dubious worth. (BonJour, 1985, pp. 7–8)

There are, however, non-epistemic ways of assessing beliefs. The possession of certain beliefs may bring me success in various ways. Some people believe that positive thinking can aid recovery from illness. If I think in this way, then I may cope better when I am ill (even if such beliefs are false). There is therefore a sense in which such thinking is justified given the benefits it brings to my state of mind. One could call this pragmatic justification as opposed to epistemic justification. There is a philosophical argument for believing in the existence of God that relies on such a notion of justification, one that we shall discuss in chapter 16, section 4. The key to the argument is that we should believe in God, not because there is good evidence of his existence, but because of the rewards such a belief would bring if it turned out to be true; we would, for instance, have eternal life in paradise.

There are also other species of justification that must be distinguished from the epistemic notion. We may have what could be called ‘after the fact’ justification. In the play A Streetcar Named Desire, Stanley Kowalski thinks that he survived the battle of Salerno because he believed he was lucky.

Stanley: You know what luck is? Luck is believing you’re lucky. Take at Salerno. I believed I was lucky. I figured that 4 out of 5 would not come through but I would … and I did. I put that down as a rule. To hold front position in this rat-race you’ve got to believe you are lucky. (T. Williams, 1962, p. 216)

He did survive and so there is a sense in which his belief was justified, justified in that it came true. He was not, however, epistemically justified since he didn’t have a good reason to believe that he would be one of the lucky survivors – his odds were not good (as he admits); he simply had faith. There may also be broadly ethical reasons for holding certain beliefs. It could be said that you are justified in believing what your friend says, simply because she is your friend. Here we may not be talking about either pragmatic or epistemic justification: there may be nothing in it for you, and she may not be very reliable. There is nevertheless a sense in which you are right to accept what she says. We must be careful, then, to focus on the kind of justification that is ‘conducive to truth’, and not on these non-epistemic forms (although we shall see in c...