Understand Philosophy: Teach Yourself

Mel Thompson

• Publisher: Teach Yourself
• Year: 2010
• Print ISBN: 9781444104998
• eBook ISBN: 9781444130690
• Topic: Philosophy
• Subtopic: Philosophy History & Theory

This book is the essential introduction to the history of Western thought. Covering all the key thinkers, both ancient and modern, and all the major branches of philosophy, it will give you new insights about the world we live in. Packed full of examples and clear explanations, and with key terms defined and explained, it is ideal whether you are student looking for a quick refresher or just want to explore this fascinating topic out of personal interest.NOT GOT MUCH TIME?One, five and ten-minute introductions to key principles to get you started.
AUTHOR INSIGHTSLots of instant help with common problems and quick tips for success, based on the author's many years of experience.
TEST YOURSELFTests in the book and online to keep track of your progress.
EXTEND YOUR KNOWLEDGEExtra online articles at www.teachyourself.com to give you a richer understanding of psychology.
FIVE THINGS TO REMEMBERQuick refreshers to help you remember the key facts.
TRY THISInnovative exercises illustrate what you've learnt and how to use it.

1

The theory of knowledge

In this chapter you will learn:

• how Western philosophers have tackled the issue of knowledge and certainty
• how some of the best-known philosophers have described reality
• how to assess the role of your senses in understanding the world.

There are two basic questions which have been asked throughout the history of philosophy and which affect the way in which many different topics are considered:

What can we know?

This question is about the basic features of existence; not the sort of information that science gives about particular things, but the questions that lie beneath all such enquiry: questions about the fundamental nature of space, time or causality; about whether concepts like ‘justice’ or ‘love’ have any external, objective reality; about the structure of the world as we experience it. In the collected works of Aristotle, such questions were dealt with after his material on physics and were therefore called metaphysics.

But as soon as we start considering metaphysics, yet another question arises:

How can we know it?

Is there anything of which we can be absolutely certain? Do we depend entirely on our senses, or can we discover basic truths simply by thinking? How can we justify or prove the truth of what we claim? All such questions are considered under epistemology – the theory of knowledge.

But when we deal with metaphysics or epistemology, we have to communicate our thoughts in some way. The medium for this is language. We ask ‘What can we say?’ and ‘How can we say it?’ The study of the nature of language, and the way in which statements can be shown to be true or false, is another constant preoccupation of philosophy.

In this chapter we shall be examining some basic issues in metaphysics and epistemology, before going on to look at scientific knowledge and the nature of language. Once you have a sound knowledge of these areas of philosophy, it will become much easier to examine the way they are applied to various topics to be considered later – God, the mind, ethics, politics and so on. You will find that the same fundamental problems occur in all areas of study.

Empiricism and rationalism

Within epistemology (the theory of knowledge) there is a fundamental issue about whether our knowledge originates in, and is therefore dependent upon, the data we receive through our senses, or whether (since we know that all such sense data is fallible) the only true certainties are those that come from our own minds – from the way in which we think and organize our experience, from the principles of reason and logic.

Two key terms:

• Empiricism – all knowledge starts with the senses.
• Rationalism – all knowledge starts with the mind.

An example of an empiricist position is that of Hume, while a rationalist one is illustrated by Descartes. Their arguments about how we can justify our claims to knowledge will be outlined later in this chapter.

However, the issue of experience and the way the mind categorizes it is far from straightforward. A very basic problem here concerns reductionism, and the existence of, or reality of, complex entities or general concepts.

Consider these questions:

• How does a painting relate to the individual pigments or threads of canvas of which is it made?
• How does music relate to vibrations in the air?
• How does a person relate to the individual cells in his or her body?
• How does a nation relate to the citizens of which it is made up?

A ‘reductionist’ approach to metaphysics takes the ‘nothing but’ view, for example that music is ‘nothing but’ vibrations in the air.

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Reductionism and practical decisions …

When, on Christmas Day, the British and German soldiers facing one another in the First World War came out of their trenches, played football together and shared cigarettes, they ceased to be merely representatives of nations and acted as individuals. Later, they returned to their trenches and continued to kill one another. Which is more real – a nation or the individuals who make it up? Which should guide action? Should we act as individuals, framing political decisions on the basis of what individuals want, or should we give primacy to the ‘nation’ or the ‘class’, even if individuals have to suffer as a result? That is a matter for ethics, but we can go further and ask, ‘Do nations actually exist? Is there any such thing as society, or are there just people and families?’ These are fundamental, abstract questions, but they have important practical and moral consequences.

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If you believe that the ultimate reality is matter – the solid external world that we experience through our senses – then you are probably going to call yourself a materialist. On the other hand, if you hold that the basic reality is mental – that the world of your experience is in fact the sum of all the sensations and perceptions that have registered in your mind – you may call yourself an idealist.

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Insight

Although idealism sounds improbable, consider this: How can you tell whether, at this moment, you are dreaming or experiencing the external, physical world? If you just consider the experience you have, it’s not quite as simple as common sense would suggest.

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Knowledge and justification: are you certain?

Whenever I experience something, that experience involves two things:

1. The sensations of sight, sound, taste, touch or smell, all of which seem to me to be coming from outside myself, and therefore to be giving me information about the world.
2. My own senses. If I am partially deaf, I may be mistaken in what I hear. If I am colour-blind I will not be able to distinguish certain patterns, or appreciate the subtleties of a multicoloured fabric. If I am asleep, all sorts of things may go on around me of which I am quite unaware.

Imagine that I am taken to a police station and questioned about something that is alleged to have happened in the recent past. I give my account of what I have heard or seen. If it sounds credible, or agrees with the evidence of others, I am likely to be believed. On the other hand, the police may ask, ‘Are you sure about that? Is it possible that you were mistaken?’ The implication is that, even if I am trying to be accurate and honest, the senses may be mistaken, and there may be two quite different ways of interpreting an experience.

When philosophers ask, ‘What can be known for certain?’ or ‘Are the senses a reliable source of knowledge?’ they are trying to sort out this element of uncertainty, so as to achieve statements that are known to be true.

Basically, as we saw above, there are two ways of approaching this problem, corresponding to the two elements in every experience.

• Empiricists are those who start with the sensations of an experience, and say that all of our knowledge of the world is based on sensation.
• Rationalists are those who claim that the basis of knowledge is the set of ideas we have – the mental element that sorts out and interprets experience. Rationalists consider the mind to be primary, and the actual data of experience to be secondary.

But before we look at these approaches in more detail, let us be clear about one category of things that we can know for certain. If I say that 2 + 2 = 4, there is no doubt about the truth of that statement. Mathematics and logic work from agreed definitions. Once those are accepted, certain results follow. They do not depend upon particular situations or experiences.

In general terms I can say that: If A = B + C, and if B and C are contained in, or implied by, the definition of A, then that statement will always be true. Understand the words and you understand its truth. Statements that are true by definition, although they are important, need not therefore detain us.

DESCARTES (1596–1650)

René Descartes placed one question centre-stage: ‘Of what can I be certain?’ He used the method of systematic doubt, by which he would only accept what he could see clearly and distinctly to be true. He knew that his senses could be deceived, therefore he would not trust them, nor could he always trust his own logic. He realized that he might even be dreaming what he took to be a waking reality. His approach is one that will be examined below, in the section on Scepticism. Yet the one thing Descartes could not doubt was his own existence. If he doubted, he was there to doubt; therefore he must exist. The famous phrase which expresses this is ‘cogito ergo sum’ (‘I think, therefore I am’). His argument is set out in his Discourse on Method (Section 4), 1637:

But then, immediately, as I strove to think of everything as false, I realized that, in the very act of thinking everything false, I was aware of myself as something real; and observing that the truth: I think, therefore I am, was so firm and so assured that the most extravagant arguments of the sceptics were incapable of shaking it, I concluded that I might have no scruple in taking it as the first principle of philosophy for which I was looking.

Penguin Classics (trans. A. Wollaston), 1960

Descartes could doubt even his own body but, while doubting, he could not deny himself as a thinking being. All else was open to the challenge that he could be mistaken.

In many ways, Descartes’ argument represents the starting point of modern philosophy (modern, that is, as compared to that of the ancient Greeks and of the medieval world), not because later thinkers have been in agreement with him but because, challenged by scepticism, they have followed his quest to find the basis of certainty and knowledge. In other words, Descartes set the theory of knowledge at the heart of the philosophical agenda.

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Insight

Do we always need to be that sceptical about what we experience? After all, we live with the assumption that the world is what we perceive it to be. Might it not be better to take a pragmatic view and not challenge what works perfectly well most of the time?

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RUSSELL (1872–1970)

Bertrand Russell’s early philosophy was as hugely influential as his later writings were popular. He contributed to mathematics and logic, and introduced analytic philosophy, an approach that dominated the Anglo – American philosophical scene for half a century.

Moving on from Descartes’ systematic doubt, a useful next step is to look at Russell’s analysis of experience in his book The Problems of Philosophy (1912). He examines the table at which he sits to write. He observes that its appearance changes in different light and from different positions, and comes to the conclusion that our sense perceptions (the actual experiences of colour, shape and texture) are not the same thing as the table itself (otherwise we would have to say that the table becomes black once the light is turned out, or that it gets smaller when we walk away from it), but that we have to infer the table from those perceptions.

He therefore distinguishes sense data from the ‘physical object’ that gives rise to them.

He refers to Bishop Berkeley (see p. 19), who argued that there is nothing given in our perception of something that proves it exists even when nobody is perceiving it. In order to maintain continuity when things are not being observed, Berkeley used the idea that they were being observed by God. In other words, what we call matter (the external physical world) is only known to exist in dependence upon minds that perceive it.

Having commented on Descartes’ systematic doubt, Russell points out that common sense suggests that there are ongoing objects, and that they do continue to exist when not being observed.

He gives the example of a cloth thrown over a table. Once that is done, the table cannot be observed, but it is implied by the shape of the cloth, apparently suspended in mid air. He also considers the situation where a number of people look at the same table. Unless there were to be some underlying reality, there seems to be little reason why everyone should see exactly the same thing.

He takes the idea of a cat which becomes equally hungry whether it is being observed or not. If it did not exist except when being observed, this would not make sense. Indeed, he points out that the cat’s hunger is something that one cannot observe directly, and therefore (in terms of sense data) it does not exist.

All ...

Table of contents

• Cover
• Title
• Copyright
• Dedication
• Contents
• Acknowledgements
• Meet the author
• Only got a minute?
• Only got five minutes?
• Only got ten minutes?
• Introduction
• 1 The theory of knowledge
• 2 The philosophy of science
• 3 Language and logic
• 4 The philosophy of mind
• 5 The philosophy of religion
• 6 Ethics
• 7 Political philosophy
• 8 Continental philosophy
• 9 Some other branches of philosophy
• 10 The scope of philosophy today
• Taking it further
• Glossary
• Index