In this chapter we consider a classic ‘nugget’ of an argument due to John Stuart Mill (1806–75). It comes from his Principles of Political Economy which was first published in 1848 and which ran to seven editions in his own lifetime.

James Mill, John Stuart Mill's father, and his friend Jeremy Bentham founded and promulgated the philosophy of ‘utilitarianism’ which was based on the doctrine that actions are good in so far as they ‘promote the greatest happiness of the greatest number’. James Mill was a highly educated man in many spheres and he took sole charge of his son's education from the beginning. He began to teach his son Greek at the age of three. They sat at the same table at which his father worked and, since there were no such things as English-Greek dictionaries,

In this chapter we show how to analyse and evaluate a very famous argument due to Thomas Malthus (1766–1834) and we apply and develop the method of Chapter 2 in the process. Malthus's father was a friend of David Hume and of Jean-Jacques Rousseau, both of whom visited his house together when Thomas was only three weeks old. It was under the influence of Rousseau's Emile that his father had Thomas privately educated until he became an undergraduate at Jesus College, Cambridge, at the age of eighteen, in 1784. He graduated well in mathematics in 1788, and he took Holy Orders in the same year. His Essay on the Principle of Population as it affects the Future Improvement of Society with Remarks on the Speculations of Mr. Godwin, M. Condorcet and other Writers was first published in 1798. There was much discussion at that time – in the wake of the French Revolution – about the possibility of establishing a society based on social and economic equality. Malthus's Essay originated as a polemic against such utopian speculations. His argument was not new,

Does God exist? There are many fascinating arguments which relate to this subject and in this chapter we look at just two. We do this partly to give more examples which use our method of analysing and evaluating arguments, but also to see how the method copes with two distinctive kinds of argument – one rhetorical and one philosophical. We begin with a piece by Richard Dawkins called ‘The more you understand evolution, the more you move towards atheism’ and then we look at a piece by A. J. Ayer.

SECTION A: DAWKINS

Dawkins: ‘The more you understand evolution, the more you move towards atheism’

Dr Richard Dawkins is Professor of Public Understanding of Science at Oxford University. He is famous worldwide for his work in biology, especially as he explains it in a number of very readable books including The Selfish Gene, The Blind Watchmaker, River Out of Eden and several others. The following piece is an edited version of a speech he made at the Edinburgh International Science Festival on 15 April 1992. It is reprinted from the Independent newspaper with the permission of Dr Dawkins (paragraphs are labelled for ease of subsequent reference).

1. (a) As a Darwinian, something strikes me when I look at religion. Religion shows a pattern of heredity which I think is similar to genetic heredity. The vast majority of people have an allegiance to one particular religion. There are hundreds of different religious sects, and every religious person is loyal to just one of these.

2. […]

The arguments we consider in this chapter are about nuclear deterrence. This is a subject in which reasoning plays an enormously important part. Deciding which is the best policy is not simply a matter of discovering the facts about the weapons systems available to the two sides because it is hard to tell what these facts imply about intentions under deterrence, nor is it simply a matter of resolving to defend oneself since the difference between defensive and aggressive acts is obscure under deterrence. The importance of the arguments cannot be disputed, so how should we resolve them?

This chapter attempts to contribute to the debate not directly, but by explaining a method of analysing arguments using two specimen texts from the very extensive literature on the subject. The texts we have chosen are quite typical: there are certainly many other pieces expressing similar arguments and no doubt many of these would have served our purpose equally well; however, our focus of interest is not on these particular texts (typical or not) but in the method of assessing them. We succeed in our objective if the reader grasps the method of analysis explained by reference to these examples and is then able to apply it to other pieces of reasoning.

This book arose out of my experience of teaching logic. Like many others I hoped that teaching logic would help my students to argue better and more logically. Like many others, I was disappointed. Students who were well able to master the techniques of logic seemed to find that these were of very little help in handling real arguments. The tools of classical logic – formalisation, truth-tables, Venn diagrams, semantic tableaux, etc. – just didn't seem to apply in any straightforward way to the reasoning which students had to read in courses other than logic. At the same time I felt that it ought to be possible to give students some guidance – some procedure – which would help them to extract and to evaluate arguments from written texts and which would help them to write good arguments of their own. I wanted the procedure to be non-formal but to build upon the insights of traditional logic; this book attempts to realise that objective.

Many other teachers of logic and philosophy have had much the same experience in the past two decades and the result has been the emergence of what is now called the ‘informal logic and critical thinking movement’ in North America. One of the first books in this tradition was Monroe Beardsley's Practical Logic, a book which is still well worth reading over thirty years on. Stephen Toulmin's The Uses of Argument is another classic attempt at providing an alternative framework for understanding reasoning.

In Chapter 1 we considered several examples; most of them were arguing a case and we used them to point up various lessons about reasoning. Having given the reader a taste of argument analysis we now introduce a general method for analysing and evaluating arguments. The method lay behind what was said in Chapter 1 but the reader who tried the exercises should now be ready for a general account rather than the piecemeal approach.

The method which we describe applies to reasoning, or argument, as it actually occurs in natural language – in our case, English. We begin by describing how to recognise contexts in which reasoning is taking place (i.e. we say what the ‘linguistic clues’ are). We then describe how to uncover and display the structure of a piece of reasoning (whether it is a ‘chain’ of reasons etc.). Finally we explain, as far as possible, how to decide whether the reasoning is correct or incorrect.

At this stage we do no more than outline the method. We do this so that its essential lines may be boldly drawn and clearly grasped. Too many qualifications at this point might obscure the method's basic simplicity: if it is basically correct the place to develop and refine it is where the problems arise – in applying it to particular examples – and this is what we shall do. In subsequent chapters the basic skeleton will be extended and ‘fleshed out’ as the need arises.

‘Supposition’ explained: and how to handle simple cases

In this chapter we deal with a distinctive kind of reasoning – suppositional reasoning. Most informal logic/critical thinking texts make no mention of it at all (although there are some notable exceptions, for example Stephen Thomas's Practical Reasoning in Natural Language). This is surprising since this kind of reasoning is elegant, powerful, and extremely common, as we shall illustrate in the next three chapters.

The arguments considered in most texts employ only assertions: in speaking of reasons and conclusions they are always talking about asserted propositions – propositions which their authors have put forward as being true (cf. our remarks on assertion in Chapter 2, p. 23). However, some arguments reach their conclusion not by asserting their starting points, but by assuming or supposing something ‘for the sake of argument’ as it is often described.

If someone begins an argument by saying ‘Suppose that oxygen does not burn’ he is not asserting that oxygen does not burn – he is not presenting this as true. Indeed he may well know that oxygen burns and he may be setting out on a reductio ad absurdum argument to prove that it does. Suppositions then are not assertions.

An atheist who begins to argue her case by saying, ‘Suppose there is an omniscient Being of the sort in which Christians believe’, is not asserting (claiming) that there is a Christian God (because she doesn't believe that there is one).

It is likely that anyone who has read this far will be interested in the extent to which formal logic can help in extracting and evaluating arguments. There is no doubt that traditional formal logic contains many ideas and insights which are useful if one is to understand and evaluate arguments. On the other hand it is clearly difficult to apply it to real arguments – to arguments of the kind one finds for example in newspapers, magazines and learned journals.

Elementary classical logic articulates a very clear theory and one which is quite easy to understand. This Appendix is addressed to the reader who knows little or no formal logic but who would like a brief introduction to the subject so that he or she may begin to consider what help logic can give in argument analysis. There are scores of elementary logic texts which develop carefully and clearly the material which we review very briefly here.

What is argument?

Reasoning, or arguing a case, consists in giving reasons for some conclusion: the reasons are put forward in order to establish, support, justify, prove or demonstrate the conclusion.

We learn most of what we know from teachers and experts of one kind and another and this is not surprising in a highly specialised modern society. However, it is possible to rely too heavily on experts and this approach to learning and knowledge tends to encourage passivity and receptiveness rather than inventiveness and imagination. We tend to think that because the teachers and experts know more about the subject than the rest of us we must ask for their judgement and we must rely on it. One object of this book is to combat this attitude and to impress on the reader what a long way one can get in understanding any subject by thinking it through for oneself, by being imaginative and inventive rather than by simply accepting expert opinion. We shall do this by concentrating on the arguments experts have produced for believing a wide range of things and showing how it requires only a relatively slight knowledge of the subject to evaluate these arguments oneself. (When we speak of an argument in this book, we mean a train of reasoning – not a quarrel!) Confidence in one's own judgement is another key to understanding and a secondary objective of this book is to give the reader such confidence. It's like learning to ride a bicycle – you will have some falls on the way but once you can do it you'll realise you can do a great deal on your own.

In this chapter, I consider the views of Thomas Reid concerning our knowledge of the reliability of our faculties. Reid holds that it is a “first principle” that perception and memory and, indeed, all of our natural cognitive faculties are reliable. Yet, in several places, he seems to endorse ways of supporting the reliability of our faculties that seem to be epistemically circular. In the first section, I shall examine some of these passages. In the second section, I shall consider a brief yet important criticism Reid makes of Descartes. Reid argues that Descartes's argument that his faculties are reliable is question-begging. If Reid's criticism of Descartes is sound, then it seems that any reasoning for the reliability of our faculties must also be question-begging. I will argue, however, that Reid's charge that Descartes begs the question rests on a mistaken view of what knowledge requires. It also seems to be a view that is inconsistent with positions that Reid endorses elsewhere. Reid's endorsement of this mistaken view seems to be a lapse on his part.

REID ON OUR KNOWLEDGE OF THE RELIABILITY OF OUR FACULTIES

Kant is among the most prominent critics of the common sense tradition, at least as it is represented by Reid. In Kant's view, it is an appeal to the opinion of the multitude, of which a real philosopher ought to be ashamed. In one blistering passage, Kant writes:

In Chapter 2, we considered Sosa's view that epistemic circularity does not prevent us from knowing that our faculties are reliable. We looked at both track record arguments and the Neo-Moorean argument for the reliability of our faculties. In this chapter, we consider some objections raised by Richard Fumerton and Jonathan Vogel to the use of both sorts of arguments and, more generally, to the view that one may use a faculty or source of belief in order to know that it is reliable. We conclude with some further reflections on the value of track record and Neo-Moorean arguments.

FUMERTON'S OBJECTIONS

As we saw in Chapter 2, Fumerton claims that one cannot use memory to justify the reliability of memory or use sense perception to justify the reliability of sense perception. Consider the following objection raised by Fumerton:

In this chapter, I begin by describing some of the main features of the common sense tradition, whose chief representatives include Thomas Reid, G. E. Moore, and Roderick Chisholm. There are certainly important differences among the views of Reid, Moore, and Chisholm, but I think one can give a rough account of some central features of the common sense tradition. In the first section, I describe some of the main views accepted by members of the tradition as well as some views to which they are not committed. In the second section, I consider some views about why we should take various common sense propositions as data for assessing philosophical theories. Philosophers in the common sense tradition have offered different sorts of answers to this question. Sometimes they suggest that we simply have no alternative to taking these propositions as data. Sometimes, however, it is suggested that such propositions are “irresistible” – that we cannot give up our belief in them. Reid, for example, appears in places to take this view. In other cases, they point, not to irresistibility, but to the positive epistemic character of our beliefs in such propositions as that which makes them worthy of being taken as data. On this view, it is the fact that we know or are justified in believing certain propositions that makes them worthy of being taken as data. This “epistemic answer” seems to me to be the best.

Often showing only a polite interest in what I do, non-philosophers occasionally ask what I've been up to. I tell them that I've been working on a book on the common sense tradition in philosophy. Often I get a response like this: “Common sense?! What's that got to do with philosophy?” This response is (one hopes) a good-natured jab at philosophy and philosophers. Those who make it do know a little bit about philosophy. Many of them have read Hume or Berkeley or, at least, have some rough idea of their views. They know that some famous philosophers have said some pretty strange things that seem to contradict common sense. So they assume philosophy is just opposed to common sense. That seems to be, in my experience, a popular view of philosophy. Those who make these jabs are often unaware that there is another view of the matter. Thomas Reid, the Scottish contemporary and critic of Hume, wrote, “Philosophy … has no other root but the principles of Common Sense; it grows out of them, and draws its nourishment from them. Severed from this root, its honours wither, its sap is dried up, it dies and rots.”

Reid, who sought to reconcile philosophy with the principles of common sense, stands as one of the major figures in the common sense tradition. If the popular mind is largely ignorant of the common sense tradition, the same is not true of the philosophical community.

In this chapter, I consider one line of criticism of the common sense tradition. This objection holds that (1) perceptual and mnemonic knowledge require that one know that one's perception and memory are reliable, (2) the only epistemically satisfactory way to know that they are reliable is through a “non-circular” argument, and (3) the common sense philosopher has no such argument. If this objection were sound, then the common sense philosopher would not know what he thinks he knows. Many of the beliefs he takes as “data” would lack the positive epistemic status he takes them to have. In this chapter and the next, I will defend the view that we may reasonably reject both (1) and (2).

In the first section, I consider some of the assumptions that underlie this objection. In the second section, I consider the views of William Alston and Ernest Sosa concerning our knowledge of the reliability of our ways of forming beliefs. Sosa argues, roughly, that when it comes to knowing that our ways of forming beliefs are reliable, we cannot escape epistemic circularity; however, he holds that this fact does not prevent us from knowing that our ways of forming beliefs are reliable. I think Sosa's view is right, and that it provides a way in which the common sense philosopher might respond to this objection.

TWO ASSUMPTIONS

Here are two assumptions: