What is Philosophy?

1. Some philosophical question

Let's begin in the middle.

Imagine that you are an archaeologist investigating an ancient site. You discover a rock face, on which there are the following marks:

You ask yourself the question: are these marks the product of an ancient stonemason trying out a new chisel, or is this an inscription in a language I do not understand? Well, if they are an inscription in a language you do not understand, then they have a meaning, in the way that the marks you are looking at right now, on this page, have a meaning. If they are the product of a stonemason simply trying out a new chisel, though, they do not have a meaning (in that way).

But what is it for a series of marks to have a meaning in that way? What makes it true that the marks you are looking at now have a meaning, whereas the marks displayed above do not?

Try this one. One morning at breakfast you exclaim "I have an appointment with my dentist!" You gulp down your coffee, pull on a coat, and rush to the dentist's office. The receptionist looks at you with pity. "No", she says, "you don't have an appointment this morning, or any time unless you wish to make one now." Slowly you realize that you had dreamt making an appointment with your dentist. But perhaps you are dreaming now and risk being late for that appointment? How can you tell? Perhaps what you take to be your life is all a dream. Are you sure there are other people, people who want to teach you philosophy?

One more for luck. Suppose you are a surgeon with five patients in critical condition. One will die very soon if she does not get a new lung, one will die without a new kidney, another will die without a new heart, another without a new liver, and the last without a new stomach. But you also have, in your clinic right now, John Doe, a perfectly healthy young man who has come in to fix the photocopier. And you just happen to know (never mind how) that John Doe is a perfect donor for each of your desperately needy patients. So you kill him, and use his organs to save the lives of your patients. You have saved five lives at the cost of one.

Now, what you did was surely morally wrong. It is not morally permissible to treat people in the way you treated John Doe. But now exercise your imagination one last time, and suppose that you are the driver of a runaway railway engine. You have little control of the engine: you cannot stop it, or even slow it down (and it is going very, very fast). But you do have a little bit of control. If you come to a junction, for example, you can cause the engine to take the right fork, or the left fork. Now, suppose you see a junction coming up fast, and suppose that, on the right fork, there are five workmen on the line, whereas on the left fork, there is only one workman on the line. You cannot warn them of your approach, and it is highly unlikely that they will see or hear you coming (their backs are turned, and they are all listening to their iPods). Then you should take the left fork, no? You should take the left fork, because that way you will save five lives, at the cost of one.

But wait a minute! How can it be morally required that you save five lives, at the cost of one, in the runaway train example, but morally wrong to save five lives, at the cost of one, in the surgeon example?

Are you intrigued? Would you like to be able to think effectively, creatively, clearly, and deeply about these sorts of questions? If you would, then you should study philosophy.

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2. Studying philosophy

The study of philosophy will help you to think about questions of these sorts. Philosophical perplexity, coupled with the desire to develop these intellectual skills, is the best motivation for the study of philosophy. We do not promise that you will end up with convincing answers to the questions that trouble you. But we do promise that you will end up with a much deeper understanding of why questions of this sort are so challenging, so important, and so intellectually rewarding.

How does the study of philosophy do this? Some people take a philosophy course because a certain type of question, like those in the examples above, fascinates them. Others take a philosophy course because they want to know what some of the great philosophers in the Western tradition have thought; perhaps they have heard of Plato, or Descartes, or Kant. Or one may take a philosophy course because one wants to learn something about the philosophical views common in some non-Western culture. Whatever brings you to a philosophy course, you will discover that there are two things that make the study of philosophy exciting: first, you will come to understand views that you had never even imagined, and you will find that there are actually reasons for holding these views; second, you will exercise all your critical faculties as you try to evaluate these views, asking yourself whether the arguments presented are cogent and whether the views are true. You will discover that different philosophers offer radically different answers to the same, or what seems to be the same, question. Obviously, you are not expected to accept all of these views; in fact, you are not expected to accept any of them. You are only expected to think for yourself, critically and intensely, on philosophical issues. You may spend a long time simply trying to understand what some philosopher has said, but once you have understood a position, even if you do not adopt it, you will have acquired another perspective on some important issue.

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3. The Structure of the Subject

In choosing a sequence of courses for a major or minor in philosophy, it is important that you have some sense of the overall shape of the subject, the way in which its various divisions are interrelated. This will help you to understand the various distribution requirements that the department makes.

Philosophy is a single discipline, not a collection of separable ones. As a result, any categorization of its various subdivisions is apt to be somewhat artificial. Nevertheless, it is common, and useful, to divide the subject into the following broad areas:

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(a) Metaphysics and epistemology

Metaphysics and epistemology are the core of philosophy.

Metaphysics attempts to arrive at a characterization of reality as whole, in its most general features. The metaphysician tries to explain what the world is like, at the most fundamental level. A crucial aspect of this project is to explain the place of human beings in the scheme of things.

Thus, materialism, the view that reality as a whole consists entirely of little bits of matter, organized into a variety of structures, is a metaphysical view. So is idealism - the view that reality as a whole is mental, consisting of minds and their contents, and relations amongst minds.

Epistemology (also known as the theory of knowledge) attempts to give an account of the scope and nature of human knowledge - and therefore also of the limitations of human knowledge.

Thus, empiricism - the view that all our knowledge of reality comes via the use of our bodily senses - is an epistemological view. So is rationalism - the view that our reason, independently of the senses, can provide us with at least some knowledge of reality.

Any metaphysical position will give rise to epistemological problems, and vice versa. Suppose, for example, you are a materialist. Your metaphysical view is likely to have the consequence that there are no mathematical objects (no numbers, functions, vectors etc.). But now the materialist faces a serious epistemological problem: how is mathematical knowledge possible? For we do seem to know quite a lot about numbers, functions, vectors etc. The materialist has to deny that there is any mathematical knowledge, or say that mathematical knowledge is not at all what it appears to be (in particular, it is not knowledge of numbers, functions, vectors, etc.). Neither alternative is easy to defend.

Or, to take another example, suppose you favor an empiricist epistemology. Your epistemological view may have the consequence that you can't really know anything about values - in particular, about ethical values. (For consider: your senses can inform you that Jane is setting fire to the cat, but how could they inform you of the wrongness of setting fire to the cat?) And that in turn may have consequences for your metaphysical opinions - in particular, it may force you to deny that ethical values are part of reality.

Philosophy is the reflective discipline par excellence, and one of the things that philosophers have reflected on with the greatest intensity is the nature of reasoning - reasoning in general, but also philosophical reasoning in particular. That is the subject matter of logic. In doing philosophy, we constantly use the distinctive vocabulary of logical appraisal: we say this is not true, this does not follow from that, or this is inconsistent, or this provides good evidence for that. Logic, broadly considered, tries to arrive at an articulate understanding of these notions. Logic, therefore, is the primary tool of the philosophers' trade, and in studying logic, you are studying the skills that enable you to function.

But logic gives rise to distinctively philosophical questions all on its own. Philosophers have long wondered whether there were intrinsic limitations to the power of human reason - whether there were questions to which we could not hope to know the answer because of our inherent limitations as human beings. Logic speaks directly to this question (and the answer it gives is, roughly, yes). Many philosophers have believed that logic alone, without the aid of experience, could inform us of at least the most basic features of reality. Again, logic speaks directly to this question (and this time, the answer it gives is that this belief is almost certainly false).

Logic is standardly divided into two parts, deductive and inductive (the distinction concerns the way in which the premises and conclusion of an argument are related). Nowadays, you are most likely to encounter a discussion of inductive logic in a course on the philosophy of (natural) science, because inductive reasoning is the basis of a great deal of the reasoning in the natural sciences. (That is how we do it here: 216 (Logic) is devoted to deductive logic; induction is usually a central topic in 217 (Philosophy of Science).) But some philosophical reasoning is inductive in character also.

Again, inductive reasoning gives rise to distinctively philosophical questions. Why is it that the natural sciences have been so strikingly successful in explaining the things we observe in the physical world? This is, in part, a question about inductive reasoning - a question about what constitutes good evidence for the truth of an empirical claim, and what makes good evidence good. Is the methodology of natural science appropriate for use in the social sciences? Again, this is in part a question about inductive reasoning, its scope and limitations.

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(b) Value theory

Metaphysical and epistemological problems arise in every area of philosophy (this is one reason why metaphysics and epistemology are the core of the subject). For example, value theory comprises ethics, political philosophy, and aesthetics - the theories of the good, the right, the just, and the beautiful. One ethical question that intrigues almost everyone concerns the objectivity of ethical values. Is there only one true morality, or many? Is morality objective (binding everyone, everywhere, at all times) or relative (changing as people, places, and times change)? This is, in part, a metaphysical problem about ethical values. Part of what we want to know is whether ethical values are part of the fabric of reality itself. It is also, in part, an epistemological problem about ethical values. For how can we hope to know which ethical theory is the right one (or, to put it another way, how is ethical knowledge possible)?

Aesthetics gives rise to similar questions. What are we doing when we say that a painting, say, is beautiful? Are we simply reporting a subjective reaction, a mere personal feeling, or are we trying to capture some objective feature of the painting - one that anyone ought to recognize? There is a metaphysical component to this question, and also an epistemological one.

But there are many other fascinating questions in the area of value theory which are not just special cases of general metaphysical and aesthetic questions. Ethicists and political philosophers nowadays are increasingly concerned with some pressing practical issues. Political philosophers think about abortion rights, and the equitable distribution of medical care. Ethicists think about what morality requires of us in the treatment of animals. There are questions about the environment and the treatment of the earth's natural resources which lend themselves very well to the special skills of the ethicist and the political philosopher. There are questions about the provision of public subsidies for the arts which cannot be addressed unless you are prepared to give a great deal of thought to the kind of value that art has for us, the place that it occupies in a meaningful and fulfilling human life; and those issues take you quickly into the domain of philosophical aesthetics.

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(c) The history of philosophy

Philosophical problems are deep and difficult, and you may be inclined to despair of finding solutions to them. But remember that some of the greatest of all thinkers have struggled with them, over a period of two thousand years and more. There is an ongoing philosophical conversation with an unbroken history going back to the fifth century BC, and in the course of that conversation many very good, very interesting solutions have been given. In studying philosophy, in however humble a capacity, you are contributing to that conversation. You will learn a great deal about philosophy by studying the solutions of your predecessors - even if, in the end, you decide that they are wrong. This is the area covered by the history of philosophy.

There are at least four reasons why philosophers must study the history of philosophy. The first and most important is the intrinsic philosophical interest of the great classics of philosophy. Beginning to grasp the depths of Descartes' Meditations on First Philosophy, or Kant's Critique of Pure Reason, is quite simply as thrilling an experience as the intellectual life has to offer. Secondly, philosophy is an ongoing conversation, and it is hard to understand the stage we have now reached in this conversation without some sense of how the conversation has developed over time. Thirdly, the history of philosophy provides perspective on current philosophical debates. It makes you aware of alternative possibilities, different way of seeing things - ways that are apt to become obscured by the shifting tides of philosophical fashion. And fourthly, the close study of the works of Aristotle, Kant, Frege, etc. provides the philosopher with a sense of how one does philosophy - a feel for the kinds of questions that are genuinely philosophical, and a feel for the way in which questions of that sort can be fruitfully tackled.

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(d) The philosophy of [S]

Metaphysics and epistemology, value theory, and the history of philosophy are the main subdivisions of philosophy. But you may well have heard of many other branches of philosophy not included in this list. For example, you will see books and courses with titles like "Philosophy of Psychology", "Philosophy of Biology", "Philosophy of Economics". For just about every subject S, there seems also to be a subject called "Philosophy of S". Why is this?

Well, look back at the characterization of metaphysics given above. "The metaphysician", it says, "tries to arrive at a characterization of reality as a whole, in its most general features". You will not get very far towards that goal without coming across some puzzling questions about more specific topics. Consider, for example, space and time. Is there only one space, or could there be many different spaces? Could time somehow run out? Could time have a beginning? These are genuinely philosophical questions, but they also encroach on the distinctive territory of physics and astronomy. You cannot hope to answer them convincingly without some knowledge of modern physics.

Equally, though, physics alone does not provide answers to the philosophers' questions. So there is room here for a very specialized and demanding part of philosophy, one that requires the skills of the physicist and the philosopher. Hence, the philosophy of physics. This is not a part of philosophy in the same way that metaphysics, say, is part of philosophy. Rather, the philosophy of physics addresses metaphysical and epistemological problems in the light of the discoveries of modern physics.

In a similar way, almost every subject contributes something to the characterization of reality as a whole. So almost every subject has a distinctively philosophical dimension, one which leaves room for there to be a philosophy of that subject. Hence, the philosophy of S, for variable S. Many philosophy of S courses fall under the heading "Metaphysics and Epistemology", but some, like Philosophy of Art, fall under "Value Theory".

Many people come to philosophy via problems they have first encountered in another discipline. An economist, for example, might become intrigued by the notion of rationality found in discussions of economic planning, which may lead her towards some distinctively philosophical problems. So economic philosophy may be, for her, the best way into philosophy as a whole.

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