## What Shanl We Mam?

# The Tragedy of the Commons

## The population problem has no technical solution;

## it requires a fundamental extension in morality.

```
Garrett Hardin
```


##### and,morespecifically,withtheidentifi-

##### cationanddiscussionofone ofthese.

```
the arms race are ... confronted by the
```

dilemma of steadily increasing military

```
power and steadily decreasing national
```

```
security. It is our considered profes-
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```
sional judgment that this dilemma has
```

```
no technical solution. If the great pow-
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ers continue to look for solutions in

```
the area of science and technology only,
```

```
the result will be to worsen the situa-
```

tion."

```
I would like to focus your attention
```

not on the subject of the article (na-

tional security in a nuclear world) but

on the kind of conclusion they reached,

namely that there is no technical solu-

tion to the problem. An implicit and

almost universal assumption of discus-

sions published in professional and

semipopular scientific journals is that

the problem under discussion has a

technical solution. A technical solution

may be defined as one that requires a

change only in. the techniques of the

natural sciences, demanding little or

nothing in the way of change in human

values or ideas of morality.

```
In our day (though not in earlier
```

times) technical solutions are always

welcome. Because of previous failures

in prophecy, it takes courage to assert

that a desired technical solution is not

possible. Wiesner and York exhibited

this courage; publishing in a science

journal, they insisted that the solution

to the problem was not to be found in

the natural sciences. They cautiously

qualified their statement with the

phrase, "It is our considered profes-

```
The author is professor of biology, University
```

of California, Santa Barbara. This article is

based on a presidential address presented before

the meeting of the Pacific Division of the Ameri-

can Association for the Advancement of Science

at Utah State University, Logan, [^25]: June 1968.

[^13]: DECEMBER 1968

```
sional judgment... ." Vhether they
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were right or not is not the concern of
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```
the present article. Rather, the concern
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here is with the important concept of a
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class of human problems which can be
```

```
called "no technical solution problems,"
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```
and, more specifically, with the identifi-
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cation and discussion of one of these.
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It is easy to show that the class is not
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a null class. Recall the game of tick-
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tack-toe. Consider the problem, "How
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can I win. the game of tick-tack-toe?"
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It is well known that I cannot, if I as-
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sume (in keeping with the conventions
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```
of game theory) that my opponent un-
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derstands the game perfectly. Put an-
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other way, there is no "technical solu-
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tion" to the problem. I can win only
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by giving a radical meaning to the word
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"win." I can hit my opponent over the
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head; or I can drug him; or I can falsify
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the records. Every way in which I "win"
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involves, in some sense, an abandon-
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ment of the game, as we intuitively un-
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derstand it. (I can also, of course,
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openly abandon the game-refuse to
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play it. This is what most adults do.)
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The class of "No technical solution
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problems" has members. My thesis is
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that the "population problem," as con-
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ventionally conceived, is a member of
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this class. How it is conventionally con-
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ceived needs some comment. It is fair
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to say that most people who' anguish
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over the population problem are trying
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to find a way to avoid the evils of over-
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population without relinquishing any of
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the privileges they now enjoy. They
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think that farming the seas or develop-
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ing new strains of wheat will solve the
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```
problem-technologically. I try to show
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here that the solution they seek cannot
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be found. The population problem can-
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not be solved in a technical way, any
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```
more than can the problem of winning
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```
the game of tick-tack-toe.
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Population, as Malthus said, naturally
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tends to grow "geometrically," or, as we
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would now say, exponentially. In a
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finite world this means that the per
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capita share of the world's goods must
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steadily decrease. Is ours a finite world?
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A fair defense can be put forward for
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the view that the world is infinite; or
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that we do not know that it is not. But,
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in terms of the practical problems that
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we must face in the next few genera-
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tions with the foreseeable technology, it
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is clear that we will greatly increase
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human misery if we do not, during the
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immediate future, assume that the world
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available to the terrestrial human pop-
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ulation is finite. "Space" is no escape
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(2).
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A finite world can support only a
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finite population; therefore, population
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growth must eventually equal zero. (The
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case of perpetual wide fluctuations
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above and below zero is a trivial variant
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that need not be discussed.) When this
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condition is met, what will be the situa-
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tion of mankind? Specifically, can Ben-
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tham's goal of "the greatest good for
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the greatest number" be realized?
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No-for two reasons, each sufficient
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by itself. The first is a theoretical one.
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It is not mathematically possible to
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maximize for two (or more) variables at
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the same time. This was clearly stated
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by von Neumann and Morgenstern (3),
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but the principle is implicit in the theory
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of partial differential equations, dating
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back at least to D'Alembert (1717-
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1783).

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The second reason springs directly
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from biological facts. To live, any
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organism must have a source of energy
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(for example, food). This energy is
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utilized for two puposes: mere main-
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tenance and work. For man, mainte-
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nance of life requires about 1600 kilo-
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calories a day ("maintenance calories').
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Anything that he does over and above
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merely staying alive will be defined as
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work, and is supported by "work cal-
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ories" which he takes in. Work calories
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are used not only for what we call work
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in common speech; they are also re-
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quired for all forms of enjoyment, from
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swimming and automobile racing to
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playing music and writing poetry. If
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our goal is to maximize population it is
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obvious what we must do: We must
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make the work calories per person ap-
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proach as close to zero as possible. No
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gourmet meals, no vacations, no sports,
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no music, no literature, no art.... I
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think that everyone will grant, without
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1243
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on March 12, 2021
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http://science.sciencemag.org/
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argument or proof, that maximizing
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population does not max2imize goods.
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Bentham's goal is impossible.
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In reaching this conclusion I have
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made the usual assumption that it is
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the acquisition of energy that is the
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problem. The appearance of atomic
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energy has led some to question this
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assumption. However, given an infinite
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source of energy, population growth
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still produces an inescapable problem.
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The problem of the acquisition of en-
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ergy is replaced by the problem of its
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dissipation, as J. H. Fremlin has so wit-
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tily shown (4). The arithmetic signs in
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-t-he analysis are, as it were, reversed;

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but Bentham's goal is still unobtainable.
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The optimum population is, then, less
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than the maximum. The difficulty of
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defining the optimum is enormous; so
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far as I know, no one has seriously
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tackled this problem. Reaching an ac-
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ceptable and stable solution will surely
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require more than one generation of
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hard analytical work-and much per-
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suasion.
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We want the maximum good per
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person; but what is good? To one per-
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son it is wilderness, to another it is ski
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lodges for thousands. To one it is estu-
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aries to nourish ducks for hunters to
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shoot; to another it is factory land.
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Comparing one good with another is,
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we usually say, impossible because
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goods are incommensurable. Incommen-
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surables cannot be compared.
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Theoretically this may be true; but in
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real life incommensurables are commen-
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surable. Only a criterion of judgment
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and a system of weighting are needed.
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In nature the criterion is survival. Is it
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better for a species to be small and hide-
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able, or large and powerful? Natural
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selection commensurates the incommen-
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surables. The compromise achieved de-
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pends on a natural weighting of the
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values of the variables.
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Man must imitate this process. There
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is no doubt that in fact he already does,
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but unconsciously. It is when the hidden
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decisions are made explicit that the
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arguments begin. The problem for the
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years ahead is to work out an accept-
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able theory of weighting. Synergistic
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effects, nonlinear variation, and difficul-
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ties in discounting the future make the
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intellectual problem difficult, but not
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(in principle) insoluble.
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Has any cultural group solved this
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practical problem at the present time,
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even on an intuitive level? One simple
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fact proves that none has: there is no
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prosperous population in the world to-
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day that has, and has had for some
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1244
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time,-p - rate of zero. Any people
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that has intuitively identified its opti-
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mum point will soon reach it, after
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which its growth rate becomes and re-
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mains zero.
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Of course, a positive growth rate
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might be taken as evidence that a pop-
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ulation is below its optimum. However,
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by any reasonable standards, the most
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rapidly growing populations on earth
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today are (in general) the most misera-
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ble. This association (which need not be
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invariable) casts doubt on the optimistic
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assumption that the positive growth rate
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of a population is evidence that it has
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yet to reach its optimum.
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We can make little progress in work-
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ing toward optimum poulation size until
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we explicitly exorcize the spirit of
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Adam Smith in the field of practical
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demography. In economic affairs, The
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Wealth of Nations (1776) popularized
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the "invisible hand," the idea that an
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individual who "intends only his own
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gain," is, as it were, "led by an invisible
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hand to promote. .,. the public interest"
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(5). Adam Smith did not assert that
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this was invariably true, and perhaps
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neither did any of his followers. But he
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contributed to a dominant tendency of
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thought that has ever since interfered
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with positive action based on rational
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analysis, namely, the tendency to as-
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sume that decisions reached individually
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will, in fact, be the best decisions for an
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entire society. If this assumption is
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correct it justifies the continuance of
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our present policy of laissez-faire in
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reproduction. If it is correct we can as-
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sume that men will control their individ-
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ual fecundity so as to produce the opti-
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mum population. If the assumption is
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not correct, we need to reexamine our
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individual freedoms to see which ones
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are defensible.
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Tragedy of Freedom in a Commons
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The rebuttal to the invisible hand in
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population control is to be found in a
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scenario first sketched in a little-known
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pamphlet (6) in[^1833] by a mathematical
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amateur named William Forster Lloyd
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(1794-1852). We may well call it "the
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tragedy of the commons," using the
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word "tragedy" as the philosopher
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Whitehead used it (7): "The essence of
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dramatic tragedy is not unhappiness. It
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resides in the solemnity of the remorse-
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less working of things." He then' goes on.
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to say, "This inevitableness of destiny
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can only be illustrated in terms of hu-
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man life by incidents which in fact in-
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volve unhappiness. For it is only by
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them that the futility of escape can be
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made evident in the drama."
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The tragedy of the commons develops
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in this way. Picture a pasture open to
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all. It is to be expected that each herds-
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man will try to keep as many cattle as
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possible on the commons. Such an ar-
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rangement may work reasonably satis-
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factorily for centuries because tribal
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wars, poaching, and disease keep the
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numbers of both man and beast well
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below the carrying capacity of the land.
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Finally, however, comes the day of
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reckoning, that is, the day when the
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long-desired goal of social stability be-
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comes a reality. At this point, the in-
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herent logic of the commons remorse-
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lessly generates tragedy.
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As a rational being, each herdsman
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seeks to maximize his gain. Explicitly
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or implicitly, more or less consciously,
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he asks, "What is the utility to me of
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adding one more animal to my herd?"
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This utility has one negative and one
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positive component.
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1) The positive component is a func-
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tion of the increment of one animal.
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Since the herdsman receives all the
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proceeds from the sale of the additional
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animal, the positive utility is nearly +1.
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2) The negative component is a func-
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tion of the additional overgrazing
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created by one more animal. Since,
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however, the effects of overgrazing are
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shared by all the herdsmen, the negative
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utility for any particular decision-
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making herdsman is only a fraction of
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-1.
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Adding together the component par-
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tial utilities, the rational herdsman
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concludes that the only sensible course
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for him to pursue is to add another
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animal to his herd. And another; and
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another.... But this is the conclusion
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reached by each and every rational
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herdsman sharing a commons. Therein
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is the tragedy. Each man is locked into
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a system that compels him to increase
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his herd without limit-in a world that
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is limited. Ruin is the destination to-
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ward which all men rush, each pursuing
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his own best interest in a society that
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believes in the freedom of the com-
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mons. Freedom in a commons brings
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ruin to all.
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Some would say that this is a plati-
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tude. Would that it were! In a sense, it
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was learned thousands of years ago, but
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natural selection favors the forces of
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psychological denial (8). The individual
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benefits as an individual from his ability
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to deny the truth even though society as
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a whole, of which he is a part, suffers.
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```
SCIENCE, VOL.[^162]
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on March 12, 2021
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Education can counteract the natural
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tendency to do the wrong thing, but the
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inexorable succession of generations
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requires that the basis for this knowl-
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edge be constantly refreshed.
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A simple incident that occurred a few
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years ago in Leominster, Massachusetts,
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shows how perishable the knowledge is.
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During the Christmas shopping season
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the parking meters downtown were
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covered with plastic bags that bore tags
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reading: "Do not open until after Christ-
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mas. Free parking courtesy of the
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mayor and city council." In other words,
```

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facing the prospect of an increased de-
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mand for already scarce space, the city
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fathers reinstituted the system of the
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commons. (Cynically, we suspect that
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they gained more votes than they lost
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by this retrogressive act.)
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In an approximate way, the logic of
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the commons has been understood for
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a long time, perhaps since the dis-
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covery of agriculture or the invention
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of private property in real estate. But
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it is understood mostly only in special
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cases which are not sufficiently general-
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ized. Even at this late date, cattlemen
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leasing national land on the western
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ranges demonstrate no more than an
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ambivalent understanding, in constantly
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pressuring federal authorities to increase
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the head count to the point where over-
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grazing produces erosion and weed-
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dominance. Likewise, the oceans of the
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world continue to suffer from the sur-
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vival of the philosophy of the commons.
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Maritime nations still respond automat-
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ically to the shibboleth of the "freedom
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of the seas." Professing to believe in
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the "inexhaustible resources of the
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oceans," they bring species after species
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of fish and whales closer to extinction
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(9).

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The National Parks present another
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instance of the working out of the
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tragedy of the commons. At present,

they are open to all, without limit. The

parks themselves are limited in extent-

there is only one Yosemite Valley-

whereas population seems to grow with-

out limit. The values that visitors seek

in the parks are steadily eroded. Plainly,

we must soon cease to treat the parks

as commons or they will be of no value

to anyone.

```
What shall we do? We have several
```

options. We might sell them off as pri-

vate property. We might keep them as

public property, but allocate the right

to enter them. The allocation might be

on the basis of wealth, by the use of an

auction system. It might be on the basis

of merit, as defined by some agreed-

[^13]: DECEMBER 1968

```
upon standards. It might be by lottery.
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Or it might be on a first-come, first-
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```
served basis, administered to long
```

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queues. These, I think, are all the
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reasonable possibilities. They are all
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```
objectionable. But we must choose-or
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acquiesce in the destruction of the com-
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mons that we call our National Parks.
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Pollution
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In a reverse way, the tragedy of
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the commons reappears in problems of
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pollution. Here it is not a question of
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taking something out of the commons,
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but of putting something in-sewage,
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or chemical, radioactive, and heat
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wastes into water; noxious and danger-
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ous fumes into the air; and distracting
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and unpleasant advertising signs into
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the line of sight. The calculations of
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utility are much the same as before.
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The rational man finds that his share of
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the cost of the wastes he discharges into
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the commons is less than the cost of
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purifying his wastes before releasing
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them. Since this is true for everyone, we
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are locked into a system of "fouling our
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own nest," so long as we behave only
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as independent, rational, free-enter-
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prisers.
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The tragedy of the commons as a
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food basket is averted by private prop-
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erty, or something formally like it. But
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the air and waters surrounding us can-
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not readily be fenced, and so the trag-
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edy of the commons as a cesspool must
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be prevented by different means, by co-
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ercive laws or taxing devices that make
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it cheaper for the polluter to treat his
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pollutants than to discharge them un-
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treated. We have not progressed as far
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with the solution of this problem as we
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have with the first. Indeed, our particu-
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lar concept of private property, which
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deters us from exhausting the positive
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resources of the earth, favors pollution.
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The owner of a factory on the bank of
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a stream-whose property extends to
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the middle of the stream-often has
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difficulty seeing why it is not his natural
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right to muddy the waters flowing past
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his door. The law, always behind the
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times, requires elaborate stitching and
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fitting to adapt it to this newly perceived
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aspect of the commons.
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The pollution problem is a con-
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sequence of population. It did not much
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matter how a lonely American frontiers-
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man disposed of his waste. "Flowing
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water purifies itself every 10 miles," my
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grandfather used to say, and the myth
```

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was near enough to the truth when he
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was a boy, for there were not too many
```

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people. But as population became denser,
```

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the natural chemical and biological re-
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cycling processes became overloaded,
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```
calling for a redefinition of property
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rights.

```
How To Legislate Temperance?
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```
Analysis of the pollution problem as
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a function of population density un-
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covers a not generally recognized prin-
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ciple of morality, namely: the morality
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of an act is a function of the state of
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the system at the time it is performed
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(10). Using the commons as a cesspool
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does not harm the general public under
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frontier conditions, because there is no
```

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public; the same behavior in a metropo-
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lis is unbearable. A hundred and fifty
```

```
years ago a plainsman could kill an
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American bison, cut out only the tongue
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for his dinner, and discard the rest of
```

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the animal. He was not in any impor-
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tant sense being wasteful. Today, with
```

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only a few thousand bison left, we
```

```
would be appalled at such behavior.
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In passing, it is worth noting that the
```

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morality of an act cannot be determined
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```
from a photograph. One does not know
```

```
whether a man killing an elephant or
```

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setting flre to the grassland is harming
```

```
others until one knows the total system
```

```
in which his act appears. "One picture
```

```
is worth a thousand words," said an
```

```
ancient Chinese; but it may take 10,000
```

```
words to validate it. It is as tempting to
```

```
ecologists as it is to reformers in general
```

```
to try to persuade others by way of the
```

```
photographic shortcut. But the essense
```

```
of an argument cannot be photo-
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```
graphed: it must be presented rationally
```

```
-in words.
```

```
That morality is system-sensitive
```

```
escaped the attention of most codifiers
```

```
of ethics in the past. "Thou shalt
```

```
not.. ." is the form of traditional
```

```
ethical directives which make no allow-
```

```
ance for particular circumstances. The
```

```
laws of our society follow the pattern of
```

```
ancient ethics, and therefore are poorly
```

```
suited to governing a complex, crowded,
```

```
changeable world. Our epicyclic solu-
```

```
tion is to augment statutory law with
```

```
administrative law. Since it is practically
```

```
impossible to spell out all the conditions
```

```
under which it is safe to burn trash in
```

```
the back yard or to run an automobile
```

```
without smog-control, by law we dele-
```

```
gate the details to bureaus. The result
```

```
is administrative law, which is rightly
```

```
feared for an ancient reason-Quis
```

```
custodiet ipsos custodes?-"Who shall
```

```
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```

```
-A
```

```
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```

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```
watch the watchers themselves?" John
```

```
Adams said that we must have "a gov-
```

```
ernment of laws and not men." Bureau
```

```
administrators, trying to evaluate the
```

```
morality of acts in the total system, are
```

```
singularly liable to corruption, produc-
```

```
ing a government by men, not laws.
```

```
Prohibition is easy to legislate
```

```
(though not necessarily to enforce); but
```

```
how do we legislate temperance? Ex-
```

```
perience indicates that it can be ac-
```

complished best through the mediation

of administrative law. We limit possi-

bilities unnecessarily if we suppose that

```
the sentiment of Quis custodiet denies
```

```
us the use of administrative law. We
```

should rather retain the phrase as a

perpetual reminder of fearful dangers

we cannot avoid. The great challenge

facing us now is to invent the corrective

feedbacks that are needed to keep cus-

todians honest. We must find ways to

legitimate the needed authority of both

the custodians and the corrective feed-

backs.

```
Freedom To Breed Is Intolerable
```

```
The tragedy of the commons is in-
```

volved in population problems in an-

other way. In a world governed solely

by the principle of "dog eat dog"-if

indeed there ever was such a world-

how many children a family had would

not be a matter of public concern.

Parents who bred too exuberantly would

leave fewer descendants, not more, be-

cause they would be unable to care

adequately for their children. David

Lack and others have found that such a

negative feedback demonstrably con-

trols the fecundity of birds (11). But

men are not birds, and have not acted

like them for millenniums, at least.

```
If each human family were depen-
```

```
dent only on its own resources; if the
```

children of improvident parents starved

to death; if, thus, overbreeding brought

its own "punishment" to the germ line-

then there would be no public interest

in controlling the breeding of families.

But our society is deeply committed to

```
the welfare state (12), and hence is
```

```
confronted with another aspect of the
```

```
tragedy of the commons.
```

```
In a welfare state, how shall we deal
```

```
with the family, the religion, the race,
```

```
or the class (or indeed any distinguish-
```

```
able and cohesive group) that adopts
```

```
overbreeding as a policy to secure its
```

```
own aggrandizement (13)? To couple
```

```
the concept of freedom to breed with
```

```
the belief that everyone born has an
```

```
1246
```

```
equal right to the commons is to lock
```

```
the world into a tragic course of action.
```

```
Unfortunately this is just the course
```

```
of action that is being pursued by the
```

```
United Nations. In late 1967, some 30
```

```
nations agreed to the following (14):
```

```
The Universal Declaration of Human
```

```
Rights describes the family as the natural
```

```
and fundamental unit of society. It fol-
```

```
lows that any choice and decision with
```

```
regard to the size of the family must irte-
```

```
vocably rest with the family itself, and
```

```
cannot be made by anyone else.
```

```
It is painful to have to deny categor-
```

```
ically the validity of this right; denying
```

```
it, one feels as uncomfortable as a resi-
```

```
dent of Salem, Massachusetts, who
```

```
denied the reality of witches in the 17th
```

```
century. At the present time, in liberal
```

```
quarters, something like a taboo acts to
```

```
inhibit criticism of the United Nations.
```

```
There is a feeling that the United
```

```
Nations is "our last and best hope,"
```

```
that we shouldn't find fault with it; we
```

```
shouldn't play into the hands of the
```

```
archconservatives. However, let us not
```

```
forget what Robert Louis Stevenson
```

```
said: "The truth that is suppressed by
```

```
friends is the readiest weapon of the
```

```
enemy." If we love the truth we must
```

```
openly deny the validity of the Universal
```

```
Declaration of Human Rights, even
```

```
though it is promoted by the United
```

```
Nations. We should also join with
```

```
Kingsley Davis (15) in attempting to
```

```
get Planned Parenthood-World Popula-
```

```
tion to see the error of its ways in em-
```

```
bracing the same tragic ideal.
```

```
Conscience Is Self-Eliminating
```

```
It is a mistake to think that we can
```

```
control the breeding of mankind in the
```

```
long run by an appeal to conscience.
```

```
Charles Galton Darwin made this point
```

```
when he spoke on the centennial of the
```

```
publication of his grandfather's great
```

```
book. The argument is straightforward
```

```
and Darwinian.
```

```
People vary. Confronted with appeals
```

```
to limit breeding, some people will un-
```

```
doubtedly respond to the plea more
```

```
than others. Those who have more
```

```
children will produce a larger fraction
```

```
of the next generation than those with
```

```
more susceptible consciences. The dif-
```

```
ference will be accentuated, generation
```

```
by generation.
```

```
In C. G. Darwin's words: "It may
```

```
well be that it would take hundreds of
```

```
generations for the progenitive instinct
```

```
to develop in this way, but if it should
```

```
do so, nature would have taken her
```

```
revenge, and the variety Homo contra-
```

```
cipiens would become extinct and
```

```
would be replaced by the variety Homo
```

```
progenitivus" (16).
```

```
The argument assumes that con-
```

```
science or the desire for children (no
```

```
matter which) is hereditary-but heredi-
```

```
tary only in the most general formal
```

```
sense. The result will be the same
```

```
whether the attitude is transmitted
```

```
through germ cells, or exosomatically,
```

```
to use A. J. Lotka's term. (If one denies
```

```
the latter possibility as well as the
```

```
former, then what's the point of educa-
```

```
tion?) The argument has here been
```

```
stated in the context of the population
```

```
problem, but it applies equally well to
```

```
any instance in which society appeals
```

```
to an individual exploiting a commons
```

```
to restrain himself for the general
```

```
good-by means of his conscience. To
```

```
make such an appeal is to set up a
```

```
selective system that works toward the
```

```
elimination of conscience from the race.
```

```
Pathogenic Effects of Conscience
```

```
The long-term disadvantage of an
```

```
appeal to conscience should be enough
```

```
to condemn it; but has serious short-
```

```
term disadvantages as well. If we ask
```

```
a man who is exploiting a commons to
```

```
desist "in the name of conscience,"
```

```
what are we saying to him? What does
```

```
he hear?-not only at the moment but
```

```
also in the wee small hours of the
```

```
night when, half asleep, he remembers
```

```
not merely the words we used but also
```

```
the nonverbal communication cues we
```

```
gave him unawares? Sooner or later,
```

```
consciously or subconsciously, he senses
```

```
that he has received two communica-
```

```
tions, and that they are contradictory:
```

```
(i) (intended communication) "If you
```

```
don't do as we ask, we will openly con-
```

```
demn you for not acting like a respon-
```

```
sible citizen"; (ii) (the unintended
```

```
communication) "If you do behave as
```

```
we ask, we will secretly condemr. you
```

```
for a simpleton who can be shamed
```

```
into standing aside while the rest of us
```

```
exploit the commons."
```

```
Everyman then is caught in what
```

```
Bateson has called a "double bind."
```

```
Bateson and his co-workers have made
```

```
a plausible case for viewing the double
```

```
bind as an important causative factor in
```

```
the genesis of schizophrenia (17). The
```

```
double bind may not always be so
```

```
damaging, but it always endangers the
```

```
mental health of anyone to whom it is
```

```
applied. "A bad conscience," said
```

```
Nietzsche, "is a kind of illness."
```

```
To conjure up a conscience in others
```

```
SCIENCE, VOL.[^162]
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is tempting to anyone who wishes to
```

```
extend his control beyond the legal
```

```
limits. Leaders at the highest level
```

```
succumb to this temptation. Has any
```

```
President during the past generation
```

```
failed to call on labor unions to moder-
```

```
ate voluntarily their demands for higher
```

```
wages, or to steel companies to honor
```

```
voluntary guidelines on prices? I can
```

```
recall none. The rhetoric used on such
```

```
occasions is designed to produce feel-
```

```
ings of guilt in noncooperators.
```

```
For centuries it was assumed without
```

```
proof that guilt was a valuable, perhaps
```

```
even an indispensable, ingredient of the
```

```
civilized life. Now, in this post-Freudian
```

```
world, we doubt it.
```

```
Paul Goodman speaks from the
```

```
modern point of view when he says:
```

```
"No good has ever come from feeling
```

```
guilty, neither intelligence, policy, nor
```

```
compassion. The guilty do not pay
```

```
attention to the object but only to them-
```

```
selves, and not even to their own in-
```

```
terests, which might make sense, but to
```

```
their anxieties" (18).
```

```
One does not have to be a profes-
```

```
sional psychiatrist to see the conse-
```

```
quences of anxiety. We in the Western
```

```
world are just emerging from a dreadful
```

```
two-centuries-long Dark Ages of Eros
```

```
that was sustained partly by prohibi-
```

```
tion laws, but perhaps more effectively
```

```
by the anxiety-generating mechanisms
```

```
of education. Alex Comfort has told the
```

```
story well in The Anxiety Makers (19);
```

```
it is not a pretty one.
```

```
Since proof is difficult, we may even
```

```
concede that the results of anxiety may
```

```
sometimes, from certain points of view,
```

```
be desirable. The larger question we
```

```
should ask is whether, as a matter of
```

```
policy, we should ever encourage the
```

```
use of a technique the tendency (if not
```

```
the intention) of which is psycholog-
```

```
ically pathogenic. We hear much talk
```

```
these days of responsible parenthood;
```

```
the coupled words are incorporated
```

```
into the titles of some organizations de-
```

```
voted to birth control. Some people
```

```
have proposed massive propaganda
```

```
campaigns to instill responsibility into
```

```
the nation's (or the world's) breeders.
```

```
But what is the meaning of the word
```

responsibility in this context? Is it not

merely a synonym for the word con-

science? When we use the word re-

sponsibility in the absence of substantial

sanctions are we not trying to browbeat

a free man in a commons into acting

against his own interest? Responsibility

is a verbal counterfeit for a substantial

quid pro quo. It is an attempt to get

something for nothing.

```
13 DECEMBER 1968
```

```
If the word responsibility is to be
```

```
used at all, I suggest that it be in the
```

```
sense Charles Frankel uses it (20).
```

```
"Responsibility," says this philosopher,
```

```
"is the product of definite social ar-
```

```
rangements." Notice that Frankel calls
```

```
for social arrangements-not propa-
```

ganda.

```
Mutual Coercion
```

```
Mutually Agreed upon
```

```
The social arrangements that produce
```

```
responsibility are arrangements that
```

```
create coercion, of some sort. Consid-
```

```
er bank-robbing. The man who takes
```

```
money from a bank acts as if the bank
```

```
were a commons. How do we prevent
```

```
such action? Certainly not by trying to
```

```
control his behavior solely by a verbal
```

```
appeal to his sense of responsibility.
```

```
Rather than rely on propaganda we
```

```
follow Frankel's lead and insist that a
```

```
bank is not a commons; we seek the
```

```
definite social arrangements that will
```

```
keep it from becoming a commons.
```

```
That we thereby infringe on the free-
```

```
dom of would-be robbers we neither
```

```
deny nor regret.
```

```
The morality of bank-robbing is
```

```
particularly easy to understand because
```

```
we accept complete prohibition of this
```

```
activity. We are willing to say "Thou
```

```
shalt not rob banks," without providing
```

```
for exceptions. But temperance also can
```

```
be created by coercion. Taxing is a good
```

```
coercive device. To keep downtown
```

```
shoppers temperate in their use of
```

```
parking space we introduce parking
```

```
meters for short periods, and traffic
```

```
fines for longer ones. We need not
```

```
actually forbid a citizen to park as long
```

```
as he wants to; we need merely make it
```

```
increasingly expensive for him to do so.
```

```
Not prohibition, but carefully biased
```

```
options are what we offer him. A Madi-
```

```
son Avenue man might call this per-
```

```
suasion; I prefer the greater candor of
```

```
the word coercion.
```

```
Coercion is a dirty word to most
```

```
liberals now, but it need not forever be
```

```
so. As with the four-letter words, its
```

```
dirtiness can be cleansed away by ex-
```

```
posure to the light, by saying it over and
```

```
over without apology or embarrassment.
```

```
To many, the word coercion implies
```

```
arbitrary decisions of distant and irre-
```

```
sponsible bureaucrats; but this is not a
```

```
necessary part of its meaning. The only
```

```
kind of coercion I recommend is mutual
```

```
coercion, mutually agreed upon by the
```

```
majority of the people affected.
```

```
To say that we mutually agree to
```

```
coercion is not to say that we are re-
```

```
quired to enjoy it, or even to pretend
```

```
we enjoy it. Who enjoys taxes? We all
```

```
grumble about them. But we accept
```

```
compulsory taxes because we recognize
```

```
that voluntary taxes would favor the
```

```
conscienceless. We institute and (grum-
```

```
blingly) support taxes and other coercive
```

```
devices to escape the horror of the
```

```
commons.
```

```
An alternative to the commons need
```

```
not be perfectly just to be preferable.
```

```
With real estate and other material
```

```
goods, the alternative we have chosen
```

```
is the institution of private property
```

```
coupled with legal inheritance. Is this
```

```
system perfectly just? As a genetically
```

```
trained biologist I deny that it is. It
```

```
seems to me that, if there are to be dif-
```

```
ferences in individual inheritance, legal
```

```
possession should be perfectly cor-
```

```
related with biological inheritance-that
```

```
those who are biologically more fit to
```

```
be the custodians of property and power
```

```
should legally inherit more. But genetic
```

```
recombination continually makes a
```

```
mockery of the doctrine of "like father,
```

```
like son" implicit in our laws of legal in-
```

```
heritance. An idiot can inherit millions,
```

```
and a trust fund can keep his estate
```

```
intact. We must admit that our legal
```

```
system of private property plus inheri-
```

```
tance is unjust-but we put up with it
```

```
because we are not convinced, at the
```

```
moment, that anyone has invented a
```

```
better system. The alternative of the
```

```
commons is too horrifying to contem-
```

```
plate. Injustice is preferable to total
```

```
ruin.
```

```
It is one of the peculiarities of the
```

```
warfare between reform and the status
```

```
quo that it is thoughtlessly governed
```

```
by a double standard. Whenever a re-
```

```
form measure is proposed it is often
```

```
defeated when its opponents trium-
```

```
phantly discover a flaw in it. As Kings-
```

```
ley Davis has pointed out (21), worship-
```

```
pers of the status quo sometimes imply
```

```
that no reform is possible without unan-
```

```
imous agreement, an implication con-
```

```
trary to historical fact. As nearly as I
```

```
can make out, automatic rejection of
```

```
proposed reforms is based on one of
```

```
two unconscious assumptions: (i) that
```

```
the status quo is perfect; or (ii) that the
```

```
choice we face is between reform and
```

```
no action; if the proposed reform is
```

```
imperfect, we presumably should take
```

```
no action at all, while we wait for a
```

```
perfect proposal.
```

```
But we can never do nothing. That
```

```
which we have done for thousands of
```

```
years is also action. It also produces
```

```
evils. Once we are aware that the
```

```
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```

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```

status quo is action, we can then com-

pare its discoverable advantages and

disadvantages with the predicted ad-

vantages and disadvantages of the pro-

posed reform, discounting as best we

can for our lack of experience. On the

basis of such a comparison, we can

make a rational decision which will not

involve the unworkable assumption that

only perfect systems are tolerable.

Recognition of Necessity

```
Perhaps the simplest summary of this
```

analysis of man's population problems

is this: the commons, if justifiable at

all, is justifiable only under conditions

of low-population density. As the hu-

man population has increased, the

commons has had to be abandoned in

one aspect after another.

```
First we abandoned the commons in
```

```
food gathering, enclosing farm land
```

and restricting pastures and hunting

```
and fishing areas. These restrictions
```

```
are still not complete throughout the
```

```
world.
```

```
Somewhat later we saw that the com-
```

```
mons as a place for waste disposal
```

```
would also have to be abandoned. Re-
```

```
strictions on the disposal of domestic
```

```
sewage are widely accepted in the
```

```
Western world; we are still struggling
```

```
to close the commons to pollution by
```

```
automobiles, factories, insecticide
```

```
sprayers, fertilizing operations, and
```

```
atomic energy installations.
```

```
In a still more embryonic state is our
```

```
recognition of the evils of the commons
```

```
in matters of pleasure. There is almost
```

```
no restriction on the propagation of
```

```
sound waves in the public medium. The
```

```
shopping public is assaulted with mind-
```

```
less music, without its consent. Our
```

```
government is paying out billions of
```

```
dollars to create supersonic transport
```

```
which will disturb 50,000 people for
```

```
every one person who is whisked from
```

```
coast to coast[^3] hours faster. Adver-
```

```
tisers muddy the airwaves of radio and
```

```
television and pollute the view of
```

```
travelers. We are a long way from out-
```

```
lawing the commons in matters of
```

```
pleasure. Is this because our Puritan
```

```
inheritance makes us view pleasure as
```

```
something of a sin, and pain (that is,
```

```
the pollution of advertising) as the sign
```

```
of virtue?
```

```
Every new enclosure of the com-
```

```
mons involves the infringement of
```

```
somebody's personal liberty. Infringe-
```

```
ments made in the distant past are ac-
```

```
cepted because no contemporary com-
```

```
plains of a loss. It is the newly pro-
```

```
posed infringements that we vigorously
```

```
oppose; cries of "rights" and "freedom"
```

```
fill the air. But what does "freedom"
```

```
mean? When men mutually agreed to
```

```
pass laws against robbing, mankind be-
```

```
came more free, not less so. Individuals
```

```
locked into the logic of the commons
```

```
are free only to bring on universal ruin;
```

```
once they see the necessity of mutual
```

```
coercion, they become free to pursue
```

```
other goals. I believe it was Hegel who
```

```
said, "Freedom is the recognition of
```

```
necessity."
```

```
The most important aspect of neces-
```

```
sity that we must now recognize, is the
```

```
necessity of abandoning the commons
```

```
in breeding. No technical solution can
```

```
rescue us from the misery of overpopu-
```

```
lation. Freedom to breed will bring
```

```
ruin to all. At the moment, to avoid
```

```
hard decisions many of us are tempted
```

```
to propagandize for conscience and
```

```
responsible parenthood. The tempta-
```

```
tion must be resisted, because an ap-
```

```
peal to independently acting con-
```

```
sciences selects for the disappearance
```

```
of all conscience in the long run, and
```

```
anin,crease in anxiety in the short.
```

```
The only way we can preserve and
```

```
nurture other and more precious free-
```

```
doms is by relinquishing the freedom
```

```
to breed, and that very soon. "Freedom
```

```
is the recognition of necessity"-and it
```

```
is the role of education to reveal to all
```

```
the necessity of abandoning the free-
```

```
dom to breed. Only so, can we put an
```

```
end to this aspect of the tragedy of the
```

```
commons.
```

```
References
```

1. J. B. Wiesner and H. F. York, Sci. Amer.

```
211 (No. 4),[^27] (1964).
```

2. G. Hardin, J. Hered. 50,[^68] (1959); S. von

```
Hoernor, Science 137,[^18] (1962).
```

3. J. von Neumann and 0. Morgenstern, Theory

```
of Games and Economic Behavior (Princeton
```

```
Univ. Press, Princeton, N.J., 1947), p. 11.
```

4. J. H. Fremlin, New Sci., No.[^415] (1964), p. 285.
5. A. Smith, The Wealth of Nations (Modem

```
Library, New York, 1937), p. 423.
```

6. W. F. Lloyd, Two Lectures on the Checks to

```
Population (Oxford Univ. Press, Oxford, Eng-
```

```
land, 1833), reprinted (in part> in Population,
```

```
Evolution, and Birth Control, G. Hardin,
```

```
Ed. (Freeman, San Francisco, 1964), p. 37.
```

7. A. N. Whitehead, Science and the Modern

```
World (Mentor, New York, 1948), p. 17.
```

8. G. Hardin, Ed. Population, Evolution, and

```
Birth Control (Freeman, San Francisco, 1964),
```

```
p. 56.
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1248 SCIENCE, VOL.[^162]
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The Tragedy of the Commons

Garrett Hardin

DOI: 10.1126/science.162.3859.1243

Science [^162]: (3859), 1243-1248.

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ARTICLE TOOLS http://science.sciencemag.org/content/162/3859/1243
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REFERENCES
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