Practical ethics covers a wide area. We can find ethical ramifications in most of our choices, if we look hard enough. This
book does not attempt to cover the whole area. The problems it deals with have been selected on two grounds: relevance and
the extent to which philosophical reasoning can contribute to discussion of them.
The most relevant ethical issues are those that confront us daily: is it right to spend money on entertaining ourselves when
we could use it to help people living in extreme poverty? Are we justified in treating animals as nothing more than machines
producing flesh for us to eat? Should we drive a car – thus emitting greenhouse gases that warm the planet – if we could walk,
cycle or use public transport? Other problems, like abortion and euthanasia, fortunately are not everyday decisions for most
of us; but they are still relevant because they can arise at some time in our lives. They are also issues of current concern
about which any active participant in a democratic society should have informed and considered opinions.
The extent to which an issue can be usefully discussed philosophically depends on the kind of issue it is. Some issues are
controversial largely because there are facts in dispute.
Should we build nuclear power stations to replace the coal-fired ones that are a major cause of global warming? The answer
to that question seems to hang largely on whether it is possible to make the nuclear fuel cycle safe, both against accidental
release of radioactive materials and against terrorist attacks. Philosophers are unlikely to have the expertise to answer
this question. (That does not mean that they can have nothing to say about it – for instance, they may still be able to say
something useful about whether it is acceptable to run
a given risk.)
In other cases, however, the facts are clear and accepted by both sides, and it is conflicting ethical views that give rise
to disagreement over what to do. The important facts about abortion are not really in dispute – as we shall see in Chapter
6, when does a human life begin? is really a question of values rather than of facts – but the ethics of abortion is hotly
disputed. With questions of this kind, the methods of reasoning and analysis in which philosophers engage really can make
a difference. The issues discussed in this book are ones in which ethical, rather than factual, disagreement plays a major
role. Thinking about them philosophically should enable us to reach better-justified conclusions.
Practical Ethics, first published in 1980, has been widely read, used in many courses at universities and colleges and translated into fifteen
languages. I always expected that many readers would disagree with the conclusions I defend. What I did not expect was that
some would try to prevent the book's arguments being discussed. Yet in the late 1980s and early 1990s, in Germany, Austria and Switzerland, opposition to the views on euthanasia contained
in this book reached such a peak that conferences or lectures at which I was invited to speak were cancelled, and courses
taught by professors at German universities in which the book was to be used were subjected to such repeated disruption that
they had to be abandoned. In Zurich in 1991, when I was attempting to lecture, a protester leapt onto the stage, tore my glasses
from my face, threw them down on the floor and stamped on them. Less violent protests took place at Princeton University in 1999, when I was appointed to a chair of bioethics. People objecting
to my views barred the entrance to the central administrative building of the university, demanding that my appointment be
rescinded. Steve Forbes, a trustee of the university and at the time a candidate for the Republican nomination for the President
of the United States, announced that as long as I was at the university, he would withhold further donations to it. Both the
university president and I received death threats. To its great credit, the university stood firm in its defence of academic freedom.
The protests led me to reflect on whether the views defended in this book really are so erroneous or so dangerous that they
would be better left unsaid. Although many of the protesters were simply misinformed about what I am saying, there is an underlying
truth to the claim that the book breaks a taboo – or perhaps more than one taboo. In Germany since the Nazi era, for many
years it was impossible to discuss openly the question of euthanasia or whether a human life may be so full of misery as not
to
be worth living.
More fundamental still, and not limited to Germany, is the taboo on comparing the value of human and nonhuman lives. In the
commotion that followed the cancellation of a conference in Germany at which I had been invited to speak, the German sponsoring
organization, to disassociate itself from my views, passed a series of motions, one of which read: ‘The uniqueness of human
life forbids any comparison – or more specifically, equation – of human existence with other living beings, with their forms
of life or interests.’
Comparing, and in some cases equating, the lives of humans and animals is exactly what some chapters of this book are about;
in fact, it could be said that if there is any single aspect of this book that distinguishes it from other approaches to such
issues as human equality, abortion, euthanasia and the environment, it is the fact that these topics are approached with a
conscious disavowal of any assumption that all members of our own species have, merely because they are members of our species,
any distinctive worth or inherent value that puts them above members of other species. The belief in human superiority is
a very fundamental one, and it underlies our thinking in many sensitive areas. To challenge it is no trivial matter, and that
such a challenge should provoke a strong reaction ought not to surprise us. Nevertheless, once we have understood that the
breaching of this taboo on comparing humans and animals is partially responsible for the protests, it becomes clear that there
is no going back. For reasons that are developed in subsequent chapters, to prohibit any cross-species comparisons would be
philosophically indefensible. It would also make it impossible to overcome the wrongs we are now doing to nonhuman animals
and would reinforce attitudes that have done irreparable damage to the environment of our planet.
So I have not backed away from the views that have caused so much controversy. If these views have their dangers, the danger
of attempting to continue to silence criticism of widely accepted ideas is greater still. Since the days of Plato, philosophy
has advanced dialectically as philosophers have offered reasons for disagreeing with the views of other philosophers. Learning
from disagreement leads us to a more defensible position and is one reason why, even if the views I hold are mistaken, they
should be discussed.
Though I have not changed my views on those topics – euthanasia and abortion – against which most of the protests were directed,
this third edition is significantly different from the first and second editions. Every chapter has been reworked, factual
material has been updated, and where my position has been misunderstood by my critics, I have tried
to make it clearer. On some issues, new questions and new arguments relevant to old questions have emerged. In the discussion
of the moral status of early human life, for instance, scientific advances have led to a new debate about the destruction
of human embryos to obtain stem cells. The developing scientific understanding of early human life has not only given rise
to hopes of major gains in treating disease; it has also demonstrated that many cells – not only the fertilized egg – contain
the potential to start a new human life. We need to ask whether this changes the arguments about the moral status of human
embryos and, if so, in what way.
The sections of the book that have left me in the greatest philosophical uncertainty are those parts of Chapters 4 and 5 that
discuss whether there is some sense in which bringing into existence a new being – whether a human being or a nonhuman animal
– can compensate for the death of a similar being who has been killed. That issue in turn leads to questions about the optimum
population size and whether the existence of more sentient beings enjoying their lives would, other things being equal, be
a good thing. These questions may seem arcane and far removed from the ‘practical ethics’ promised by the title of this book,
but they have important ethical implications. As we shall see, they can serve as an example of how our judgments of what is
right and wrong need to be informed by investigations into deep and difficult philosophical issues. In revising these sections
for this edition, I have found myself unable to maintain with any confidence that the position I took in the previous edition
– based solely on preference utilitarianism – offers a satisfactory answer to these quandaries.
That reconsideration of my earlier position is the most significant philosophical change to this edition. The addition with
the greatest practical importance, however, is a new chapter that deals with the great moral challenge of our time – climate
change. Too often, we fail to see climate change as an ethical issue. I hope this chapter will show clearly that it is. The
number of chapters in this edition remains the same as it was for the second edition because a chapter that I added to that
edition, on our obligation to accept refugees, does not appear in this edition. This is not because the issue of admitting
refugees has become any less important than it was in 1993.
On the contrary, it is probably more significant now and will become more significant still, in coming decades, as we begin
to see increasing numbers of ‘climate refugees’ – people who can no longer live where their parents and grandparents lived,
because rainfall patterns have changed or sea levels have risen. But I had become dissatisfied with
the chapter as it stood. This is partly because the issue is one to which the facts – for example, about the possibility of
a country taking in large numbers of refugees without this leading to a racist backlash that would harm minority groups within
the country – are highly relevant. I had also become more aware of differences between countries that are relevant to this
issue, and so I reluctantly concluded that any attempt to deal with the issue in a single chapter of a volume such as this,
aimed at an international audience, is bound to be superficial. If the issue cannot be treated adequately and in a properly
nuanced way, I decided, it would be better not to include it in this book, especially as it is one of those issues on which
governments must set policy rather than one on which individuals actions can make a significant difference.
In writing and revising this book, I have made extensive use of my own previously published articles and books. Chapter 3
is based on my book,
Animal Liberation (2nd edition, New York Review/Random House, 1990), although it also takes account of objections made since the book first
appeared in 1975. The sections of Chapter 6 on such topics as in vitro fertilization, the argument from potential, embryo
experimentation and the use of fetal tissue, all draw on work I wrote jointly with Karen Dawson, which was published as “IVF
and the Argument from Potential”, in
Philosophy and Public Affairs, vol. 17 (1988) and in Peter Singer, Helga Kuhse and others,
Embryo Experimentation (Cambridge University Press, 1990). In the third edition, this chapter includes material responding to the arguments of Patrick
Lee and Robert George that first appeared in Agata Sagan and Peter Singer, “The Moral Status of Stem Cells”,
Metaphilosophy, 38 (2007). Chapter 7 contains material from the much fuller treatment of the issue of euthanasia for severely disabled infants
that Helga Kuhse and I provided in
Should the Baby Live? (Oxford University Press, 1985). Chapter 8 restates arguments from “Famine, Affluence and Morality”,
Philosophy and Public Affairs, vol. 1 (1972), and for this edition, I drew on my much more recent and comprehensive account of the issue in
The Life You Can Save (Random House, 2009). The new Chapter 9 draws on material first published in
One World (Yale University Press, 2002) and from “Climate Change as an Ethical Issue”, in Jeremy Moss (ed.),
Climate Change and Social Justice (Melbourne University Press, 2009). Chapter 10 is based on “Environmental Values”, a chapter I contributed to Ian Marsh (ed.),
The Environmental Challenge (Longman Cheshire, Melbourne, 1991). Portions of Chapter 11 draw on my first book,
Democracy and Disobedience (Oxford, Clarendon Press, 1973). The revisions for the third edition also include passages from my responses
to critics in
Peter Singer Under Fire, edited by Jeff Schaler (Open Court, Chicago, 2009).
H. J. McCloskey, Derek Parfit and Robert Young provided useful comments on a draft version of the first edition of this book.
Robert Young's ideas also entered into my thinking at an earlier stage, when we jointly taught a course on these topics at
La Trobe University. The chapter on euthanasia, in particular, owes much to his ideas, though he may not agree with everything
in it. Going back further still, my interest in ethics was stimulated by H. J. McCloskey, whom I was fortunate to have as
a teacher during my undergraduate years; and the mark left by R. M. Hare, who taught me at Oxford, is apparent in the ethical
foundations underlying the positions taken in this book. Jeremy Mynott of Cambridge University Press encouraged me to write
the book and helped to shape and improve it as it went along. The second edition of the book benefited from work I did with
Karen Dawson, Paola Cavalieri, Renata Singer and especially Helga Kuhse. For this third edition, I must give what are, sadly,
posthumous thanks to Brent Howard, a gifted thinker who several years ago sent me extensive notes for a possible revision
of the second edition. I am also most grateful to Agata Sagan for suggestions and research assistance throughout the revision
of the book. Her contribution is most evident in the discussion of the moral status of embryos and stem cells, but her ideas
and suggestions have improved the book in several other areas as well.
There are, of course, many others with whom I have discussed the issues that are the subject of this book. Back in 1984, Dale
Jamieson made me aware of the significance of climate change as an ethical issue, and I continue to check my thoughts on that
topic and on many others with him. I have learned a lot from Jeff McMahan, from personal contact, from a graduate seminar
we co-taught on issues of life and death and from his many writings. At Princeton University, I have often benefited from
comments on my work from my colleagues, from visiting Fellows at the University Center for Human Values and from students,
both graduate and undergraduate. Don Marquis and David Benatar each spent a year at the Center, and those visits provided
opportunities for many good discussions. I also thank my colleagues and the graduate students at the Centre for Applied Philosophy
and Public Ethics at the University of Melbourne for their comments at occasional lectures and seminars at which I have presented
my work.
Harriet McBryde Johnson and I disagreed vehemently about euthanasia for infants with severe disabilities, but there was never
any acrimony
between us, and she always presented my views with scrupulous fairness. Sadly, our exchanges ended with her death in 2008,
and I miss her critical presence.
The astute reader who compares this edition with the previous one may notice that I am now more ready to entertain – although
not yet embrace – the idea that there are objective ethical truths that are independent of what anyone desires. I owe that
shift – which could not be adequately explored in a book of this nature – to my reading of a draft of Derek Parfit's immensely
impressive forthcoming book, On What Matters. I hope to write more about this question on another occasion.