Introduction: Methods and Interests

 


 

The Study of Argument

 

It’s pretty clear from our discussion of Socrates that arguments are at the heart of philosophy. Of course the same might be said for many types of study, but philosophy is different in at least two ways. In the first place, philosophy has no other method of establishing its results (such as they are) but argument. There is no experimental component, no documentary or archival component, no observational component to philosophy. There is nothing but argument. In the second place, the nature of argument is itself of interest to a philosopher. The kinds of arguments that there are and how effective they are are themselves the subjects of study (and argument of course.)

 

The point of studying arguments in an abstract way is that it allows us to know things about particular arguments in which we may be more immediately interested. It’s often possible, for example to determine whether an argument is good or bad without knowing anything at all about the actual content of the argument. Sometimes it is the shape of the argument alone that is important. The branch of philosophy that deals most abstractly with argument is called logic, and though we won’t actually study it, since it’s a bit dry and technical for an introductory course, we’ll often have occasion to use its terminology and discoveries in the rest of the course, so here are a few brief comments that I hope will be useful. I’m also going to use this to show you how we talk abstractly about arguments so you won’t be too alarmed when this sort of thing occurs in later lectures - when we discuss things that are already hard enough to understand.

 

To start with the very basics: arguments are tools for persuading people of things. They offer a number of reasons or premises that are supposed to support a conclusion. There are two different big classes of arguments that are distinguished by the degree to which the premises are supposed to support the conclusion.

 

  1. Deductive arguments are arguments where the premises are supposed to give perfect support for the conclusion. The classic deductive argument is:

 

                                Socrates is a man

                                All men are mortal

                                Therefore Socrates is mortal

 

              Where the reasons are written above the line and the conclusion is below it.

              You can see here that if the premises are true then the conclusion must be true. This is the definition of a valid deductive argument. On the other hand, any               deductive argument in which the conclusion could – somehow – be false even when the reasons are true is an invalid argument.

 

  1. Inductive arguments, by contrast are not supposed to give perfect support for their conclusions. Here’s a perfectly standard, if somewhat boring, inductive argument:

 

                                Swan number 1 is white

                                Swan number 2 is white

                                Therefore all swans are white

 

              This is not a good inductive argument. In a good one if the premises are true then they make the conclusion probably true. This is the definition of a strong               inductive argument. On the other hand, an inductive argument like the example, in which, even if the premises were true they wouldn’t make the conclusion               probably true, is a weak argument.

  

Logical matters

 

So let’s now have a slightly closer look at the argument that Socrates offered to Euthyphro. As we’ve interpreted it, it went something like this.

 

1.                   Socrates gets from Euthyphro a definition of ‘piety:’

Piety is what the gods love and impiety is what the gods hate.

2.                   Socrates then derives certain consequences of this definition.

Since we know that the gods have disagreements

And we know that the only fundamental causes of disagreement are differences over the matter of right and wrong.

It follows that the gods differ over right and wrong

Then, since we know that everyone loves what is right and hates what is wrong

It follows that the gods love and hate different things – or, which is the same thing, the same things are loved and hated by different gods

And we have assumed that piety is what the gods love and impiety is what the gods hate.

And so the same things are both pious and impious

3.                   Finally deriving the conclusion that:

Piety cannot be just what the gods love and impiety what they hate.

 

It’s this last step that I want to talk about. It’s a variety of a very basic deductive argument called (in Latin) modus tollens. A modus tollens argument is an argument of a very particular form. It basically goes

 

                                If A then B

                                Not B                    

                                Therefore not A

 

Where A and B stand for sentences or ‘propositions.’ It’s easy to see what’s going on here if I give a couple of simple examples:

 

Let’s replace A by ‘It has been raining’ and B by ‘The grass is wet’ in the argument form above. Then we get this argument:

 

                                If it has been raining then the grass is wet

                                The grass is not wet                                            

                                Therefore it has not been raining

 

Which you can see is a valid argument because if the reasons are true (that’s the two statements above the line) then the conclusion (below the line) must be true. It is impossible for the reasons to be true and the conclusion false.

 

If we replace A by, say, ‘Socrates is a man’, and B by ‘Socrates is mortal’, then we get the argument

 

                                If Socrates is a man then Socrates is mortal

                                Socrates is not mortal                                        

                                Therefore Socrates is not a man

 

Which is also a valid argument – despite the fact that the 2nd reason in that argument was actually false, because Socrates turned out to be quite mortal. His mortality was proved shortly after the trial that he was on his way to when he met Euthyphro. But it doesn’t matter that one of the reasons is false, because to be valid it is only necessary that if the reasons were true then the conclusion would be true. And as you can see, if those reasons were true then the conclusion would be too. If all the reasons are true, and the argument is valid then the conclusion will be true too. Just as a matter of interest, a valid argument with true reasons is called a sound argument.

 

Anyway, the important point to note is that, as you’ve probably already realised, any argument which has the modus tollens form will be valid, which is why we call it a valid form.

 

Now, this particular argument winds up with Socrates and Euthyphro deriving a contradiction, which everyone agrees can’t be a true statement: it’s never true that the sun is shining and at the very same time and place the sun is not shining, or that the grass is green and at the very same time the grass is not green, or (and this is the important point) that something is loved by the gods and at the very same time not loved by the gods. So:

 

                                If piety is what is loved by the gods then the same things are pious and not pious

                                The same things are not at the very same time pious and not pious                        

                                Therefore piety is not what is loved by the gods

 

This is obviously modus tollens where A = ‘piety is what is loved by the gods’ and B is ‘the same things are pious and not pious.’[1] Because it is modus tollens, it is valid – as I’ve just demonstrated. This means that if the reasons are true then the conclusion is true. We’ve already seen that the 2nd reason is true; but what about the first one? What about the claim that ‘If piety is what is loved by the gods then the same things are pious and not pious.’ Well, this is a statement that summarises the result of the first two steps of Socrates’s argument. Remember, they assumed the truth of Euthyphro’s claim that ‘piety is what is loved by the gods’ and derived from it by simple steps that they both agreed on that ‘the same things are pious and not pious.’ The conditional statement just summarises that process. So we have to assume that it is true also. And finally, if the argument is valid (modus tollens) and the reasons are true (so the argument is sound) then, ta dah!, the conclusion is true and ‘piety is not what is loved by the gods.’



[1] This particular style of argument is one you may have heard of: it is called reductio ad absurdum, meaning ‘reducing to an absurdity.’

 

Philosophy and science

 

The reason that I particularly wanted to introduce you to this kind of argument is because it closely resembles the methodology of a form of enquiry for which you probably already have some degree of respect. I’m talking about the methodology of Science – which we all believe has the ability to tell us true (or, at least, useful things about the world.

 

In a scientific enquiry, there is some observed phenomenon for which an explanation is sought: it may be that we are wondering why a compass needle points towards the North, or why a stick appears to bend as it goes into the water, or why water boils when it is heated. How is it that scientists (ideal scientists, that is) go about answering such a question? The best known account of the scientific method is one that goes by the name of the hypothetico-deductive procedure. It can be seen as a process consisting of the following four steps.

 

1.       Form a hypothesis (e.g., by generalising or by an educated guess) of some possible explanation for the phenomenon

2.                   Derive testable consequences from the hypothesis.

3.                   Test for these consequences.

4.                   Confirm or disconfirm the hypothesis.

 

If the derived consequences of the hypothesis are observed, then the hypothesis is said to be confirmed. If they are not observed, the hypothesis is said to be disconfirmed or falsified. The hypothesis is either tentatively accepted if it is confirmed by the test, or rejected or amended if ‘disconfirmed’ by the test.

 

Let’s see how this is supposed to work by considering the actual historical case of coming up with an explanation for why we sometimes see the same collections of fossilized flora and fauna on opposite sides of oceans.

 

When scientists (geographers) became aware of this phenomenon, they probably first thought that it was a simple matter of animals swimming across the water, but it quickly became clear that the sorts of animals whose fossils were being found wouldn’t have been able to swim that far because the gaps were too wide. So how could this common ecology have arisen? The first serious hypothesis was that the separate areas had been connected in the past by extensive land bridges crossing the Atlantic or the Indian oceans. Plants and animals could have moved across these bridges in the past, and become isolated from each other after the bridges were worn away over time. In support of this theory there was the observation that there were known land bridges which had connected Siberia to Alaska and Britain to Europe and that had been submerged by rising sea levels after the end of the last ice age only a few tens of thousands of years ago.

 

But there was a problem: if there had been such enormous bridges as proposed, then there ought to still be some traces of them, but there were none. Because of this (and other reasons) they could not really be happy with the land bridge idea. In the mid-twentieth century, therefore, they began to revive an old hypothesis that the continents had all been joined together at some time far in the past and had gradually drifted apart. According to this story the fossils were the remains of inhabitants of a single habitat that had subsequently been divided.

 

There were of course those who doubted this theory. Continents, after all, are made of rock and it’s hard to imagine that they move around much. Indeed, said the critics, if this theory is true then you’d have to assume that the continents were still moving. So, are they? Well, with new accurate measuring equipment it was possible to test this hypothesis too, and it was found that they were moving. As time went on, more and more evidence was found to support the theory of continental drift – what they now call Plate Tectonics – until it is now quite widely accepted.

 

The similarity of the hypothetico-deductive method to the Socratic method of elenchus should be clear. The moral of the story, however, is that we can’t take the method itself, or the use of mere logic, to be the distinctive feature of philosophical enquiry. Indeed, philosophers would like to see themselves as engaged in just the same serious enquiry into the truth of things as are scientists. More than that, they consider that science is secondary to philosophy in this pursuit. This is partly because philosophy has been done for much longer than science, but also because science tends to follow philosophy in the treatment of particular topics. For example, physics, astronomy, cosmology, chemistry, biology, mathematics, economics, psychology, cognitive science, and many others all used to be considered part of philosophy, or arose from philosophical reflections. The question that naturally arises, then, is: what makes us call the modern treatment science and the ancient treatment philosophy? Or, what was philosophy doing in those areas that science does not do?

 

The fundamental answer is that when some field of study appeals to the evidence of the natural world to answer the questions it asks then we are doing something like science, but when the answer is not thought to be discoverable by looking at the natural world then we must be doing something more like philosophy. At the early stages of those studies that I’ve named, the desirability – or even the possibility – of looking to the world for evidence to support answers was not always clear; but more than that, it takes some time and thought to sort out which parts of a field of study really are appropriate subjects of empirical research, and which parts are not. This process of definition is itself something that can only be done by philosophical methods. In the matter of ethics, for example, it is a real step forward to become aware of the distinction between what people actually do (which may be studied in the sciences of social psychology, anthropology, cultural history, ethology, etc.) and what they ought to do (which may be studied by moral philosophers) In the matter of cosmology, it is a step forward to become aware of the distinction between how and where the universe began (which may be studied by astronomers and cosmologists and physicists) and why the universe exists rather than not existing – for which no scientific answer can be had. In the study of the human mind, as we shall see, the questions of how memory works and how we sense things and how we process information are open to scientific scrutiny by psychologists and cognitive scientists, but the question of whether a machine can think like a human is not one that any science can answer (yet?)

 

Philosophy and concepts

 

 

So what role does philosophy play in the pursuit of truth – even truths about the world – if it is not apparently truth that can be tested against the world? The standard answer to such a question is that philosophy aims to clarify the concepts that we are using to understand the world. Many people claim that we make the transition from doing philosophy in some area of enquiry to doing science in that area when philosophy has clarified or corrected the concepts involved to such a degree that they correspond to the way that the world actually is and we can then ask questions that the world can answer.

 

There’s a particularly clear example of this from the early days of science & philosophy. Some of the most heated early disputes of the ancient Greek physicists were over the nature or even the possibility of change or motion. The Greeks could see as well as we can see that the world is full of change, but because of certain apparently sound arguments it sometimes seemed that change could not really be possible, and that our evidence of change must therefore be illusory. Consider, they would say, how it is possible for a ball to move. A ball cannot move to the right unless everything that was to the right of the ball is moved to make room for it. And where would all that stuff go? It would have to go into places vacated by other stuff. And then where would that stuff go. The problem is that in a universe that is full of stuff, there is no way to move stuff around. It would be like trying to move bricks around in an unbroken wall.

 

You might think that the obvious solution to this would be to suppose (as we do today) that the world isn’t just a block of stuff but has empty spaces which things can move into without first having to displace other stuff. But this solution wasn’t immediately apparent to the Greeks, because they did not properly distinguish the concepts of matter and space. We now think of matter as occupying space, but the Greeks began by thinking of matter as constituting space. And why wouldn’t they? What experience could they have had of space without matter filling it? And if matter is space, then it can make no sense to think of something moving into some space where there is no matter. (A space where there is no matter is no space at all!) Until those two concepts – and the related concept of the ‘void’ or ‘nothingness’ – had been properly distinguished, this paradox of the impossibility of change in an obviously change-filled world just could not be solved.

 

And in case you’re thinking that this sort of nonsense is far in our past, and there’s no need to keep up the philosophical work of concept clarification in a field as well developed as Physics, I would direct your attention to two much more recent difficulties. When Newton proposed that there was a force of Gravity acting between all the masses in the universe, his idea was ridiculed as requiring ‘spooky action at a distance.’ It had been clear since ancient times that the only way that one thing could cause a change in another thing was by coming into contact with it: for there are simply no other forces but mechanical forces – that’s just what forces are! But the moon doesn’t come into contact with the Earth, nor the Earth with the Sun, so it’s clearly impossible that any influences can be exerted amongst those bodies.

 

My last example is completely contemporary. Beginning in the 20th C, physicists studying the behavior of light found that they had to accept that in some situations it behaved as if it were constituted of particles and in other situations it behaved as if it were simply waves in some medium. And eventually, it was accepted that all matter showed the same tendency towards a wave-particle duality. There is more to this dualism than a mere ambiguity about what matter is, for it sometimes seems that matter looks at the circumstances and then decides how to behave, which of course is absurd. And without an example you won’t really grasp how weird matter is – so take the time sometime to look at the double slit experiment. The really impressive thing is that despite the fact that we have had to pragmatically accept this wave-particle dualism of matter for over a hundred years now, we are still in the process of trying to make conceptual sense of it.

 

Well, that’s one good reason for being interested in conceptual clarification – and thus in doing philosophy right; but there’s a more basic reason to value it, and it has to do with our nature as human beings. What chiefly characterizes us as humans, we often think, is our status as thinking, rational animals. The most striking evidence for this characterization is the fact that we, more than any other thing in the universe, can be properly described as intentional agents – which is a fancy way of saying that our actions are best predicted or explained by assuming that we use reason to decide how to achieve our desires given the things that we believe. For example, when we feel that we need to eat – that is we have a desire for food – we reason from the fact that there is food at Bond Café, and we have money to buy food at the café, and it is open now, but we are not allowed to eat in class, but we can eat later – all of which are beliefs that we have – we decide that we will walk there later to buy food. Finally, when class is finished we stand up and walk out the door and proceed in the direction of Bond Café – which is the action that we take to satisfy our desire for food.

 

Obviously, the most important parts of this Belief-Desire-Action process are internal, and involve the use of representations of the world. I mean that it’s probably not possible to think about going to the shops, or buying food there with money, or satisfying your hunger, etc. without having some concepts of those things. And the reason that this process works well for us must have something to do with the fact that the concepts correspond in some systematic way with the facts of the world. To take an extreme case, if our idea of food included things like nails and detergent, then we’d be as likely to go to Bunning’s as to Bond Café, and we’d fail to satisfy our hunger. So it’s pretty important to make sure that our concepts of things match up to what’s really going on in the world.

 

Obviously, again, we’re well past the point where we need to worry about what our concept of ‘food’ is to include, but remember that we started all this talk by looking at a particular problem that Socrates had with the concept of ‘piety’, which might seem to us still to be something a bit up in the air. Or, if you think that piety is simply a badly formed concept not referring to anything Real, then we could consider some later examples. In recent times, for example, we’ve had significant political problems which revolved around divergent understandings of concepts such as ‘human’ (in the abortion debate or the Terry Schiavo case) or with ‘privacy’, or with ‘rights’, or with ‘marriage’, or etc. As you can see from these topics, Philosophy still has a lot of work to do.