A second major topic that Nagel discusses is whether the same moral standards apply to everyone.
This is a very complex issue–more so than you might think.
Use this forum to discuss the claim:
“At least some moral standards are universal and apply to everyone, at all times, in all places.”
discussion posts might be about testing out a candidate standard, or arguing against this claim.
Another thought-provoking article about this topic is Paul Boghossian’s piece here:
Make at least one post
and comment on the following post:
“I’d have to agree on the claim “At least some moral standards are universal and apply to everyone, at all times, in all places.” I believe in this because it
doesn’t say all moral standards are universal, but “at least some” are. I’ll agree with many of you by saying that our world is far from having universal moral
standards because of different religions and cultures, but we must understand that many cultures’ moral standards are similar. Moral standards usually benefit the
society and do more good than evil. For example, I would say helping others is a universal moral standard that every group partakes in.
Of course, every moral standard has loopholes and grey areas. For example, killing someone is immoral, but killing someone in defense is fine. Or if someone is
mentally ill and does harm but knows no better that is is wrong. Everyone can interpret moral standards differently, and that is why we are lucky to have a judicial
system to interpret those grey areas. We do not live in a Utopia where every moral claim is the exact same, but I do believe in our imperfect world, the overall idea
of morality, or to do good, is universal.
What Does It All Mean?
What Zto It All Mean?
A Very Short Introduction to Philosophy
New York Oxford OXFORD UNIVERSITY PRESS
Oxford University Press
Oxford New York Toronto Delhi Bombay Calcutta Madras Karachi Petaling Jaya Singapore Hong Kong Tokyo Nairobi Dar es Salaatn Cape Town Melbourne Auckland and associated
companies in Beirut Berlín Ibadan Nicosia
Copyright © 1987 by Thomas Nagel
Published by Oxford University Press, Inc., 200 Madison Avenue, New York, New York 10016 Oxford is a registered trademark of Oxford University Press All rights
reserved. No part of this publication may be reproduced, stored in a retrieval system, or transmitted, in any form or by any means, electroníc, mechanical,
photocopying, recording, or otherwise, without the prior permission of Oxford University Press. Library of Congress Cataloging-in-Publication Data Nagel, Thomas. What
does it all mean? 1. Philosophy—Introductions. I. Title. BD21.N24 1987 100 87-14316 ISBN 0-19-505292-7 ISBN 0-19-505216-1 (pbk.)
1. 2. 3. 4. 5. 6. 7. 8. 9. 10.
Introduction How Do We Know Anything? OtherMinds The Mind-Body Problem The Meaning of Words FreeWill Right and Wrong Justice Death The Meaning of Life
3 8 19 27 38 47 59 76 87 95
35798642 Printed in the United States of America on acid-free paper
|0st¡tuto deinvesíigac.ü ,es Filosófica!
B I B u i O T . CA , BBBABDO GARCÍA MAYNEZ”
CIUDAD UMVERSITARIA MÉXICO SO, O, F
What Does It All Mean?
This book is a brief introduction to philosophy for people who don’t know the first thing about the subject. People ordinarily study philosophy only when they go to
college, and I suppose that most readers will be of college age or older. But that has nothing to do with the nature of the subject, and I would be very glad if the
book were also of interest to intelligent high school students with a taste for abstract ideas and theoretical arguments—should any of them read it. Our analytical
capacities are often highly developed before we have learned a great deal about the world, and around the age of fourteen many people start to think about
philosophical problems on their own—about what really exists, whether we can know anything, whether
What Does It All Mean?
anything is really right or wrong, whether life has any meaning, whether death is the end. These problems have been written about for thousands of years, but the
philosophical raw material comes directly from the world and our relation to it, not from writings of the past. That is why they come up again and again, in the heads
of people who haven’t read about them. This is a direct introduction to nine philosophical problems, each of which can be understood in itself, without reference to
the history of thought. I shall not discuss the great philosophical writings of the past or the cultural background of those writings. The center of philosophy lies in
certain questions which the reflective human mind finds naturally puzzling, and the best way to begin the study of philosophy is to think about them directly. Once
you’ve done that, you are in a better position to appreciate the work of others who have tried to solve the same problems. Philosophy is different from science and
from mathematics. Unlike science it doesn’t rely on experiments or observation, but only on thought. And unlike mathematics it has no formal methods of proof. It is
done just by asking questions, arguing, trying out ideas and thinking of possible arguments against them, and wondering how our concepts really work.
The main concern of philosophy is to question and understand very common ideas that all of us use every day without thinking about them. A historian may ask what
happened at some time in the past, but a philosopher will ask, “What is time?” A mathematician may investigate the relations among numbers, but a philosopher will ask,
“What is a number?” A physicist will ask what atoms are made of or what explains gravity, but a philosopher will ask how we can know there is anything outside of our
own minds. A psychologist may investigate how children learn a language, but a philosopher will ask, “What makes a word mean anything?” Anyone can ask whether it’s
wrong to sneak into a movie without paying, but a philosopher will ask, “What makes an action right or wrong?” We couldn’t get along in life without taking the ideas
of time, number, knowledge, language, right and wrong for granted most of the time; but in philosophy we investigate those things themselves. The aim is to push our
understanding of the world and ourselves a bit deeper. Obviously it isn’t easy. The more basic the ideas you are trying to investigate, the fewer tools you have to
work with. There isn’t much you can assume or take for granted. So philosophy is a somewhat dizzying activity, and few of its results go unchallenged for long.
What Does It All Mean?
Since I believe the best way to learn about philosophy is to think about particular questions, I won’t try to say more about its general nature. The nine problems
we’ll consider are these: Knowledge of the world beyond our minds Knowledge of minds other than our own The relation between mind and brain How language is possible
Whether we have free will The basis of morality What inequalities are unjust The nature of death The meaning of life They are only a selection: there are many, many
others. What I say will reflect my own view of these problems and will not necessarily represent what most philosophers think. There probably isn’t anything that most
philosophers think about these questions anyway: philosophers disagree, and there are more than two sides to every philosophical question. My personal opinión is that
most of these problems have not been solved, and that perhaps some of them never will be. But the object here is not to give answers— not even answers that I myself
may think are right—but to introduce you to the problems in a very preliminary way so that you can worry
about them yourself. Before learning a lot of philosophical theories it is better to get puzzled about the philosophical questions which those theories try to answer.
And the best way to do that is to look at some possible solutions and see what is wrong with them. I’11 try to leave the problems open, but even if I say what I think,
you have no reason to believe it unless you find it convincing. There are many excellent introductory texts that include selections from the great philosophers of the
past and from more recent writings. This short book is not a substitute for that approach, but I hope it provides a first look at the subject that is as clear and
direct as possible. If after reading it you decide to take a second look, you’ll see how much more there is to say about these problems than I say here.
How Do We Know Anything?
How Do We Know Anything?
If you think about it, the inside of your own mind is the only thing you can be sure of. Whatever you believe—whether it’s about the sun, moon, and stars, the house
and neighborhood in which you live, history, science, other people, even the existence of your own body— is based on your experiences and thoughts, feelings and sense
impressions. That’s all you have to go on directly, whether you see the book in your hands, or feel the floor under your feet, or remember that George Washington was
the first president of the United States, or that water is H2O. Everything else is farther away from you than your inner experiences and thoughts, and reaches you only
Ordinarily you have no doubts about the existence of the floor under your feet, or the tree outside the window, or your own teeth. In fact most of the time you don’t
even think about the mental states that make you aware of those things: you seem to be aware of them directly. But how do you know they really exist? Would things seem
any different to you if in fact all these things existed only in your mind—if everything you took to be the real world outside was just a giant dream or hallucination,
from which you will never wake up? If it were like that, then of course you couldn’t wake up, as you can from a dream, because it would mean there was no “real” world
to wake up into. So it wouldn’t be exactly like a normal dream or hallucination. As we usually think of dreams, they go on in the minds of people who are actually
lying in a real bed in a real house, even if in the dream they are running away from a homicidal lawnmower through the streets of Kansas City. We also assume that
normal dreams depend on what is happening in the dreamer’s brain while he sleeps. But couldn’t all your experiences be like a giant dream with no external world
outside it? How can you know that isn’t what’s going on? If all your experience were a dream with nothing outside, then any evidence you tried to use to
What Does It All Mean? prove to yourself that there was an outside world would just be part of the dream. If you knocked on the table or pinched yourself, you would
hear the knock and feel the pinch, but that would be just one more thing going on inside your mind like everything else. It’s no use: If you want to find out whether
what’s inside your mind is any guide to what’s outside your mind, you can’t depend on how things seem—from inside your mind—to give you the answer. But what else is
there to depend on? All your evidence about anything has to come through your mind—whether in the form of perception, the testimony of books and other people, or
memory—and it is entirely consistent with everything you’re aware of that nothing at all exists except the inside of your mind. It’s even possible that you don’t have
a body or a brain—since your beliefs about that come only through the evidence of your senses. You’ve never seen your brain—you just assume that everybody has one—but
even if you had seen it, or thought you had, that would have been just another visual experience. Maybe you, the subject of experience, are the only thing that exists,
and there is no physical world at all—no stars, no earth, no human bodies. Maybe there isn’t even any space. If you try to argüe that there must be an external
physical world, because you wouldn’t see 
How Do We Know Anything? buildings, people, or stars unless there were things out there that reflected or shed light into your eyes and caused your visual experiences,
the reply is obvious: How do you know that? It’s just another claim about the external world and your relation to it, and it has to be based on the evidence of your
senses. But you can rely on that specific evidence about how visual experiences are caused only ifyou can already rely in general on the contents of your mind to tell
you about the external world. And that is exactly what has been callea into question. If you try to prove the reliability of your impressions by appealing to your
impressions, you’re arguing in a circle and won’t get anywhere. The most radical conclusión to draw from this would be that your mind is the only thing that exists.
This view is called solipsism. It is a very lonely view, and not too many people have held it. As you can tell from that remark, I don’t hold it myself. If I were a
solipsist I probably wouldn’t be writing this book, since I wouldn’t believe there was anybody else to read it. On the other hand, perhaps I would write it to make my
inner life more interesting, by including the impression of the appearance of the book in print, of other people reading it and telling me their reactions, and so
forth. I might even get the impression of royalties, if I’m lucky. Perhaps you are a solipsist: in that case you
What Does It All Mean’?
How Do We Know Anything?
will regard this book as a product of your own mind, coming into existence in your experience as you read it. Obviously nothing I can say can prove to you that I
really exist, or that the book as a physical object exists. On the other hand, to conclude that you are the only thing that exists is more than the evidence warrants.
You can’t know on the basis of what’s in your mind that there’s no world outside it. Perhaps the right conclusión is the more modest one that you don’t know anything
beyond your impressions and experiences. There may or may not be an external world, and if there is it may or may not be completely different from how it seems to you
—there’s no way for you to tell. This view is called skepticism about the external world. An even stronger form of skepticism is possible. Similar arguments seem to
show that you don’t know anything even about your own past existence and experiences, since all you have to go on are the present contents of your mind, including
memory impressions. If you can’t be sure that the world outside your mind exists now, how can you be sure that you yourself existed befare now? How do you know you
didn’t just come into existence a few minutes ago, complete with all your present memories? The only evidence that you couldn’t have come into exis
tence a few minutes ago depends on beliefs about how people and their memories are produced, which rely in turn on beliefs about what has happened in the past. But to
rely on those beliefs to prove that you existed in the past would again be to argüe in a circle. You would be assuming the reality of the past to prove the reality of
the past. It seems that you are stuck with nothing you can be sure of except the contents of your own mind at the present moment. And it seems that anything you try to
do to argüe your way out of this predicament will fail, because the argument will have to assume what you are trying to prove—the existence of the external world
beyond your mind. Suppose, for instance, you argüe that there must be an external world, because it is incredible that you should be having all these experiences
without there being some explanation in terms of external causes. The skeptic can make two replies. First, even if there are external causes, how can you tell from the
contents of your experience what those causes are like? You’ve never observed any of them directly. Second, what is the basis of your idea that everything has to have
an explanation? It’s true that in your normal, nonphilosophical conception of the world, processes like those which go on in
What Does It All Mean?
How Do We Know Anything?
your mind are caused, at least in part, by other things outside them. But you can’t assume that this is true if what you’re trying to figure out is how you know
anything about the world outside your mind. And there is no way to pro ve such a principie just by looking at what’s inside your mind. However plausible the principie
may seem to you, what reason do you have to believe that it applies to the world? Science won’t help us with this problem either, though it might seem to. In ordinary
scientific thinking, we rely on general principies of explanation to pass from the way the world first seems to us to a different conception of what it is really like.
We try to explain the appearances in terms of a theory that describes the reality behind them, a reality that we can’t observe directly. That is how physics and
chemistry conclude that all the things we see around us are composed of invisibly small atoms. Could we argüe that the general belief in the external world has the
same kind of scientific backing as the belief in atoms? The skeptic’s answer is that the process of scientific reasoning raises the same skeptical problem we have been
considering all along: Science is just as vulnerable as perception. How can we know that the world outside our minds corresponds to our ideas of what would be a good
theoretical explanation of our observations? If we can’t establish the reliability of our sense experiences in relation to the external world, there’s no reason to
think we can rely on our scientific theories either. There is another very different response to the problem. Some would argüe that radical skepticism of the kind I
have been talking about is meaningless, because the idea of an external reality that no one could ever discover is meaningless. The argument is that a dream, for
instance, has to be something from which you can wake up to discover that you have been asleep; a hallucination has to be something which others (or you later) can see
is not really there. Impressions and appearances that do not correspond to reality must be contrasted with others that do correspond to reality, or else the contrást
between appearance and reality is meaningless. According to this view, the idea of a dream from which you can never wake up is not the idea of a dream at all: it is
the idea of reality— the real world in which you Uve. Our idea of the things that exist is just our idea of what we can observe. (This view is some times called
verificationism.) Sometimes our observations are mistaken, but that means they can be corrected by other observations— as when you wake up from a dream or discover
that what you thought was
What Does It All Mean? How Do We Know Anything?
a snake was just a shadow on the grass. But without some possibility of a correct view of how things are (either yours or someone else’s), the thought that your
impressions of the world are not true is meaningless. If this is right, then the skeptic is kidding himself if he thinks he can imagine that the only thing that exists
is his own mind. He is kidding himself, because it couldn’t be true that the physical world doesn’t really exist, unless somebody could observe that it doesn’t exist.
And what the skeptic is trying to imagine is precisely that there is no one to observe that or anything else—except of course the skeptic himself, and all he can
observe is the inside of his own mind. So solipsism is meaningless. It tries to subtract the external world from the totality of my impressions; but it fails, because
if the external world is subtracted, they stop being mere impressions, and become instead perceptions of reality. Is this argument against solipsism and skepticism any
good? Not unless reality can be defined as what we can observe. But are we really unable to understand the idea of a real world, or a fact about reality, that can’t be
observed by anyone, human or otherwise? The skeptic will claim that if there is an external world, the things in it are observable because
they exist, and not the other way around: that existence isn’t the same thing as observability. And although we get the idea of dreams and hallucinations from cases
where we think we can observe the contrast between our experiences and reality, it certainly seems as if the same idea can be extended to cases where the reality is
not observable. If that is right, it seems to follow that it is not meaningless to think that the world might consist of nothing but the inside of your mind, though
neither you ñor anyone else could find out that this was true. And if this is not meaningless, but is a possibility you must consider, there seems no way to prove that
it is false, without arguing in a circle. So there may be no way out of the cage of your own mind. This is sometimes called the egocentric predicament. And yet, after
all this has been said, I have to admit it is practically impossible to believe seriously that all the things in the world around you might not really exist. Our
acceptance of the external world is instinctive and powerful: we cannotjust get rid of it by philosophical arguments. Not only do we go on acting as if other people
and things exist: we believe that they do, even after we’ve gone through the arguments which appear to show we have no grounds for this belief. (We may have grounds,
within the overall
What Does It All Mean?
system of our beliefs about the world, for more particular beliefs about the existence of particular things: like a mouse in the breadbox, for example. But that is
different. It assumes the existence of the external world.) If a belief in the world outside our minds comes so naturally to us, perhaps we don’t need grounds for it.
We can just let it be and hope that we’re right. And that in fact is what most people do after giving up the attempt to prove it: even if they can’t give reasons
against skepticism, they can’t Uve with it either. But this means that we hold on to most of our ordinary beliefs about the world in face of the fact that (a) they
might be completely false, and (b) we have no basis for ruling out that possibility. We are left then with three questions: 1. Is it a meaningful possibility that the
inside of your mind is the only thing that exists—or that even if there is a world outside your mind, it is totally unlike what you believe it to be? 2. If these
things are possible, do you have any way of proving to yourself that they are not actually true? 3. If you can’t prove that anything exists outside your own mind, is
it all right to go on believing in the external world anyway?
There is one special kind of skepticism which continúes to be a problem even if you assume that your mind is not the only thing there is— that the physical world you
seem to see and feel around you, including your own body, really exists. That is skepticism about the nature or even existence of minds or experiences other than your
own. How much do you really know about what goes on in anyone else’s mind? Clearly you observe only the bodies of other creatures, including people. You watch what
they do, listen to what they say and to the other sounds they make, and see how they respond to their environment—what things attract them and what things repel them,
what they eat, and so forth. You can also cut open other creatures and look
What Does It All Mean?
at their physical insides, and perhaps compare their anatomy with yours. But none of this will give you direct access to their experiences, thoughts, and feelings. The
only experiences you can actually have are your own: if you believe anything about the mental Uves of others, it is on the basis of observing their physical
construction and behavior. To take a simple example, how do you know, when you and a friend are eating chocolate ice cream, whether it tastes the same to him as it
tastes to you? You can try a taste of his ice cream, but if it tastes the same as yours, that only means it tastes the same to you: you haven’t experienced the way it
tastes to him. There seems to be no way to compare the two fiavor experiences directly. Well, you might say that since you’re both human beings, and you can both
distinguish among flavors of ice cream—for example you can both tell the difference between chocolate and vanilla with your eyes closed—it’s likely that your fiavor
experiences are similar. But how do you know that? The only connection you’ve ever observed between a type of ice cream and a fiavor is in your own case; so what
reason do you have to think that similar correlations hold for other human beings? Why isn’t it just as consistent with all the evidence that chocolate tastes to him
the way vanilla tastes to you, and vice versa?
The same question could be asked about other kinds of experience. How do you know that red things don’t look to your friend the way yellow things look to you? Of
course if you ask him how a fire engine looks, he’ll say it looks red, like blood, and not yellow, like a dandelion; but that’s because he, like you, uses the word
“red” for the color that blood and fire engines look to him, whatever it is. Maybe it’s what you cali yellow, or what you cali blue, or maybe it’s a color experience
you’ve never had, and can’t even imagine. To deny this, you have to appeal to an assumption that fiavor and color experiences are uniformly correlated with certain
physical stimulations of the sense organs, whoever undergoes them. But the skeptic would say you have no evidence for that assumption, and because of the kind of
assumption it is, you couldn’t have any evidence for it. All you can observe is the correlation in your own case. Faced with this argument, you might first concede
that there is some uncertainty here. The correlation between stimulus and experience may not be exactly the same from one person to another: there may be slight shades
of difference between two people’s color or fiavor experience of the same type of ice cream. In fact, since people are physically different from one another, this
wouldn’t be surprising. But, you might say,
What Does It All Mean?
the difference in experience can’t be too radical, or else we’d be able to tell. For instance, chocolate ice cream couldn’t taste to your friend the way a lemon tastes
to you, otherwise his mouth would pucker up when he ate it. But notice that this claim assumes another correlation from one person to another: a correlation between
inner experience and certain kinds of observable reaction. And the same question arises about that. You’ve observed the connection between puckering of the mouth and
the taste you cali sour only in your own case: how do you know it exists in other people? Maybe what makes your friend’s mouth pucker up is an experience like the one
you get from eating oatmeal. If we go on pressing these kinds of questions relentlessly enough, we will move from a mild and harmíess skepticism about whether
chocolate ice cream tastes exactly the same to you and to your friend, to a much more radical skepticism about whether there is any similarity between your experiences
and his. How do you know that when he puts something in his mouth he even has an experience of the kind that you would cali a/lavar? For all you know, it could be
something you would cali a sound—or maybe it’s unlike anything you’ve ever experienced, or could imagine.
If we continué on this path, it leads finally to the most radical skepticism of all about other minds. How do you even know that your friend is conscious? How do you
know that there are any minds at all besides your own? The only example you’ve ever directly observed of a correlation between mind, behavior, anatomy, and physical
circumstances is yourself. Even if other people and animáis had no experiences whatever, no mental inner Ufe of any kind, but were just elabórate biological machines,
they would look just the same to you. So how do you know that’s not what they are? How do you know that the beings around you aren’t all mindless robots? You’ve never
seen into their minds—you couldn’t—and their physical behavior could all be produced by purely physical causes. Maybe your relatives, your neighbors, your cat and your
dog have no inner experiences whatever. If they don’t, there is no way you could ever find it out. You can’t even appeal to the evidence of their behavior, including
what they say—because that assumes that in them outer behavior is connected with inner experience as it is in you; and that’s just what you don’t know. To consider the
possibility that none of the people around you may be conscious produces an uncanny feeling. On the one hand it seems
What Does It All Mean?
conceivable, and no evidence you could possibly have can rule it out decisively. On the other hand it is something you can’t really believe is possible: your
conviction that there are minds in those bodies, sight behind those eyes, hearing in those ears, etc., is instinctive. But if its power comes from instinct, is it
really knowledge? Once you admit the possibility that the belief in other minds is mistaken, don’t you need something more reliable to justify holding on to it? There
is another side to this question, which goes completely in the opposite direction. Ordinarily we believe that other human beings are conscious, and almost everyone
believes that other mammals and birds are conscious too. But people differ over whether fish are conscious, or insects, worms, and jellyfish. They are still more
doubtful about whether onecelled animáis like amoebae and paramecia have conscious experiences, even though such creatures react conspicuously to stimuli of various
kinds. Most people believe that plants aren’t conscious; and almost no one believes that rocks are conscious, or kleenex, or automobiles, or mountain lakes, or
cigarettes. And to take another biological example, most of us would say, if we thought about it, that the individual cells of which our bodies are composed do not
have any conscious experiences.
How do we know all these things? How do you know that when you cut a branch off a tree it doesn’t hurt the tree—only it can’t express its pain because it can’t move?
(Or maybe it loves having its branches pruned.) How do you know that the muscle cells in your heart don’t feel pain or excitement when you run up a flight of stairs?
How do you know that a kleenex doesn’t feel anything when you blow your nose into it? A