Thursday, August 15, 2019

The Tragedy of the Commons, by Garrett Hardin

The Tragedy of the Commons 
by Garrett Hardin
From Science, Science 13 Dec 1968:

Vol. 162, Issue 3859, pp. 1243-1248
DOI: 10.1126/science.162.3859.1243

The population problem has no technical solution; it requires a fundamental extension in morality.
At the end of a thoughtful article on the future of nuclear war, Wiesner and York (1) concluded that: “Both sides in the arms race are ...confronted by the dilemma of steadily increasing military power and steadily decreasing national security. It is our considered professional judgment that this dilemma has no technical solution. If the great powers continue to look for solutions in the area of science and technology only, the result will be to worsen the situation.”
I would like to focus your attention not on the subject of the article (national security in a nuclear world) but on the kind of conclusion they reached, namely that there is no technical solution to the problem. An implicit and almost universal assumption of discussions 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 professional judgment... .” Whether they were right or not is not the concern of the present article. Rather, the concern here is with the important concept of a class of human problems which can be called “no technical solution problems,” and, more specifically, with the identification and discussion of one of these.
It is easy to show that the class is not a null class. Recall the game of tick-tack-toe. Consider the problem, “How can I win the game of tick-tack-toe?” It is well known that I cannot, if I assume (in keeping with the conventions of game theory) that my opponent understands the game perfectly. Put another way, there is no “technical solution” to the problem. I can win only by giving a radical meaning to the word “win.” I can hit my opponent over the head; or I can drug him; or I can falsify the records. Every way in which I “win” involves, in some sense, an abandonment of the game, as we intuitively understand it. (I can also, of course, openly abandon the game--refuse to play it. This is what most adults do.)
The class of “No technical solution problems” has members. My thesis is that the “population problem,” as conventionally conceived, is a member of this class. How it is conventionally conceived needs some comment. It is fair to say that most people who anguish over the population problem are trying to find a way to avoid the evils of overpopulation without relinquishing any of the privileges they now enjoy. They think that farming the seas or developing new strains of wheat will solve the problem--technologically. I try to show here that the solution they seek cannot be found. The population problem cannot be solved in a technical way, any more than can the problem of winning the game of tick-tack-toe.
What Shall We Maximize?
Population, as Malthus said, naturally tends to grow “geometrically,” or, as we would now say, exponentially. In a finite world this means that the per capita share of the world’s goods must steadily decrease. Is ours a finite world?
A fair defense can be put forward for the view that the world is infinite; or that we do not know that it is not. But, in terms of the practical problems that we must face in the next few generations with the foreseeable technology, it is clear that we will greatly increase human misery if we do not, during the immediate future, assume that the world available to the terrestrial human population is finite. “Space” is no escape (2).
A finite world can support only a finite population; therefore, population growth must eventually equal zero. (The case of perpetual wide fluctuations above and below zero is a trivial variant that need not be discussed.) When this condition is met, what will be the situation of mankind? Specifically, can Bentham’s goal of “the greatest good for the greatest number” be realized?
No--for two reasons, each sufficient by itself. The first is a theoretical one. It is not mathematically possible to maximize for two (or more) variables at the same time. This was clearly stated by von Neumann and Morgenstern (3), but the principle is implicit in the theory of partial differential equations, dating back at least to D’Alembert (1717-1783).
The second reason springs directly from biological facts. To live, any organism must have a source of energy (for example, food). This energy is utilized for two purposes: mere maintenance and work. For man, maintenance of life requires about 1600 kilocalories a day (“maintenance calories”). Anything that he does over and above merely staying alive will be defined as work, and is supported by “work calories” which he takes in. Work calories are used not only for what we call work in common speech; they are also required for all forms of enjoyment, from swimming and automobile racing to playing music and writing poetry. If our goal is to maximize population it is obvious what we must do: We must make the work calories per person approach as close to zero as possible. No gourmet meals, no vacations, no sports, no music, no literature, no art. ... I think that everyone will grant, without argument or proof, that maximizing population does not maximize goods. Bentham’s goal is impossible.
In reaching this conclusion I have made the usual assumption that it is the acquisition of energy that is the problem. The appearance of atomic energy has led some to question this assumption. However, given an infinite source of energy, population growth still produces an inescapable problem. The problem of the acquisition of energy is replaced by the problem of its dissipation, as J. H. Fremlin has so wittily shown (4). The arithmetic signs in the analysis are, as it were, reversed; but Bentham’s goal is still unobtainable.
The optimum population is, then, less than the maximum. The difficulty of defining the optimum is enormous; so far as I know, no one has seriously tackled this problem. Reaching an acceptable and stable solution will surely require more than one generation of hard analytical work--and much persuasion.
We want the maximum good per person; but what is good? To one person it is wilderness, to another it is ski lodges for thousands. To one it is estuaries to nourish ducks for hunters to shoot; to another it is factory land. Comparing one good with another is, we usually say, impossible because goods are incommensurable. Incommensurables cannot be compared.
Theoretically this may be true; but in real life incommensurables are commensurable. Only a criterion of judgment and a system of weighting are needed. In nature the criterion is survival. Is it better for a species to be small and hideable, or large and powerful? Natural selection commensurates the incommensurables. The compromise achieved depends on a natural weighting of the values of the variables.
Man must imitate this process. There is no doubt that in fact he already does, but unconsciously. It is when the hidden decisions are made explicit that the arguments begin. The problem for the years ahead is to work out an acceptable theory of weighting. Synergistic effects, nonlinear variation, and difficulties in discounting the future make the intellectual problem difficult, but not (in principle) insoluble.
Has any cultural group solved this practical problem at the present time, even on an intuitive level? One simple fact proves that none has: there is no prosperous population in the world today that has, and has had for some time, a growth rate of zero. Any people that has intuitively identified its optimum point will soon reach it, after which its growth rate becomes and remains zero.
Of course, a positive growth rate might be taken as evidence that a population is below its optimum. However, by any reasonable standards, the most rapidly growing populations on earth today are (in general) the most miserable. This association (which need not be invariable) casts doubt on the optimistic assumption that the positive growth rate of a population is evidence that it has yet to reach its optimum.
We can make little progress in working toward optimum population size until we explicitly exorcize the spirit of Adam Smith in the field of practical demography. In economic affairs, The Wealth of Nations (1776) popularized the “invisible hand,” the idea that an individual who “intends only his own gain,” is, as it were, “led by an invisible hand to promote . . . the public interest” (5). Adam Smith did not assert that this was invariably true, and perhaps neither did any of his followers. But he contributed to a dominant tendency of thought that has ever since interfered with positive action based on rational analysis, namely, the tendency to assume that decisions reached individually will, in fact, be the best decisions for an entire society. If this assumption is correct it justifies the continuance of our present policy of laissez-faire in reproduction. If it is correct we can assume that men will control their individual fecundity so as to produce the optimum population. If the assumption is not correct, we need to reexamine our individual freedoms to see which ones are defensible.
Tragedy of Freedom in a Commons
The rebuttal to the invisible hand in population control is to be found in a scenario first sketched in a little-known pamphlet (6) in 1833 by a mathematical amateur named William Forster Lloyd (1794-1852). We may well call it “the tragedy of the commons,” using the word “tragedy” as the philosopher Whitehead used it (7): “The essence of dramatic tragedy is not unhappiness. It resides in the solemnity of the remorseless working of things.” He then goes on to say, “This inevitableness of destiny can only be illustrated in terms of human life by incidents which in fact involve unhappiness. For it is only by them that the futility of escape can be made evident in the drama.”
The tragedy of the commons develops in this way. Picture a pasture open to all. It is to be expected that each herdsman will try to keep as many cattle as possible on the commons. Such an arrangement may work reasonably satisfactorily for centuries because tribal wars, poaching, and disease keep the numbers of both man and beast well below the carrying capacity of the land. Finally, however, comes the day of reckoning, that is, the day when the long-desired goal of social stability becomes a reality. At this point, the inherent logic of the commons remorselessly generates tragedy.
As a rational being, each herdsman seeks to maximize his gain. Explicitly or implicitly, more or less consciously, he asks, “What is the utility to me of adding one more animal to my herd?” This utility has one negative and one positive component.
1) The positive component is a function of the increment of one animal. Since the herdsman receives all the proceeds from the sale of the additional animal, the positive utility is nearly +1.
2) The negative component is a function of the additional overgrazing created by one more animal. Since, however, the effects of overgrazing are shared by all the herdsmen, the negative utility for any particular decision-making herdsman is only a fraction of –1.
Adding together the component partial utilities, the rational herdsman concludes that the only sensible course for him to pursue is to add another animal to his herd. And another; and another... But this is the conclusion reached by each and every rational herdsman sharing a commons. Therein is the tragedy. Each man is locked into a system that compels him to increase his herd without limit--in a world that is limited. Ruin is the destination toward which all men rush, each pursuing his own best interest in a society that believes in the freedom of the commons. Freedom in a commons brings ruin to all.
Some would say that this is a platitude. Would that it were! In a sense, it was learned thousands of years ago, but natural selection favors the forces of psychological denial (8). The individual benefits as an individual from his ability to deny the truth even though society as a whole, of which he is a part, suffers.
Education can counteract the natural tendency to do the wrong thing, but the inexorable succession of generations requires that the basis for this knowledge be constantly refreshed.
A simple incident that occurred a few years ago in Leominster, Massachusetts, shows how perishable the knowledge is. During the Christmas shopping season the parking meters downtown were covered with plastic bags that bore tags reading: “Do not open until after Christmas. Free parking courtesy of the mayor and city council.” In other words, facing the prospect of an increased demand for already scarce space. the city fathers reinstituted the system of the commons. (Cynically, we suspect that they gained more votes than they lost by this retrogressive act.)
In an approximate way, the logic of the commons has been understood for a long time, perhaps since the discovery of agriculture or the invention of private property in real estate. But it is understood mostly only in special cases which are not sufficiently generalized. Even at this late date, cattlemen leasing national land on the western ranges demonstrate no more than an ambivalent understanding, in constantly pressuring federal authorities to increase the head count to the point where overgrazing produces erosion and weed-dominance. Likewise, the oceans of the world continue to suffer from the survival of the philosophy of the commons. Maritime nations still respond automatically to the shibboleth of the “freedom of the seas.” Professing to believe in the “inexhaustible resources of the oceans,” they bring species after species of fish and whales closer to extinction (9).
The National Parks present another instance of the working out of the 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 without 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 private 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-upon standards. It might be by lottery. Or it might be on a first-come, first-served basis, administered to long queues. These, I think, are all the reasonable possibilities. They are all objectionable. But we must choose--or acquiesce in the destruction of the commons that we call our National Parks.
In a reverse way, the tragedy of the commons reappears in problems of pollution. Here it is not a question of taking something out of the commons, but of putting something in--sewage, or chemical, radioactive, and heat wastes into water; noxious and dangerous fumes into the air, and distracting and unpleasant advertising signs into the line of sight. The calculations of utility are much the same as before. The rational man finds that his share of the cost of the wastes he discharges into the commons is less than the cost of purifying his wastes before releasing them. Since this is true for everyone, we are locked into a system of “fouling our own nest,” so long as we behave only as independent, rational, free-enterprisers.
The tragedy of the commons as a food basket is averted by private property, or something formally like it. But the air and waters surrounding us cannot readily be fenced, and so the tragedy of the commons as a cesspool must be prevented by different means, by coercive laws or taxing devices that make it cheaper for the polluter to treat his pollutants than to discharge them untreated. We have not progressed as far with the solution of this problem as we have with the first. Indeed, our particular concept of private property, which deters us from exhausting the positive resources of the earth, favors pollution. The owner of a factory on the bank of a stream--whose property extends to the middle of the stream, often has difficulty seeing why it is not his natural right to muddy the waters flowing past his door. The law, always behind the times, requires elaborate stitching and fitting to adapt it to this newly perceived aspect of the commons.
The pollution problem is a consequence of population. It did not much matter how a lonely American frontiersman disposed of his waste. “Flowing water purifies itself every 10 miles,” my grandfather used to say, and the myth was near enough to the truth when he was a boy, for there were not too many people. But as population became denser, the natural chemical and biological recycling processes became overloaded, calling for a redefinition of property rights.
How to Legislate Temperance?
Analysis of the pollution problem as a function of population density uncovers a not generally recognized principle of morality, namely: the morality of an act is a function of the state of the system at the time it is performed (10). Using the commons as a cesspool does not harm the general public under frontier conditions, because there is no public, the same behavior in a metropolis is unbearable. A hundred and fifty years ago a plainsman could kill an American bison, cut out only the tongue for his dinner, and discard the rest of the animal. He was not in any important sense being wasteful. Today, with only a few thousand bison left, we would be appalled at such behavior.
In passing, it is worth noting that the morality of an act cannot be determined from a photograph. One does not know whether a man killing an elephant or setting fire 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 photographed: 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 allowance 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 solution 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 delegate the details to bureaus. The result is administrative law, which is rightly feared for an ancient reason--Quis custodiet ipsos custodes?--”Who shall watch the watchers themselves?” John Adams said that we must have “a government of laws and not men.” Bureau administrators, trying to evaluate the morality of acts in the total system, are singularly liable to corruption, producing a government by men, not laws.
Prohibition is easy to legislate (though not necessarily to enforce); but how do we legislate temperance? Experience indicates that it can be accomplished best through the mediation of administrative law. We limit possibilities 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 custodians honest. We must find ways to legitimate the needed authority of both the custodians and the corrective feedbacks.
Freedom to Breed is Intolerable
The tragedy of the commons is involved in population problems in another 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, because they would be unable to care adequately for their children. David Lack and others have found that such a negative feedback demonstrably controls 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 dependent 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--thenthere 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 distinguishable 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 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 follows that any choice and decision with regard to the size of the family must irrevocably rest with the family itself, and cannot be made by anyone else. 
It is painful to have to deny categorically the validity of this right; denying it, one feels as uncomfortable as a resident 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 Population to see the error of its ways in embracing 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 undoubtedly 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 difference 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 contracipiens would become extinct and would be replaced by the variety Homo progenitivus” (16).
The argument assumes that conscience or the desire for children (no matter which) is hereditary--but hereditary 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 education?) 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 communications, and that they are contradictory: (i) (intended communication) “If you don’t do as we ask, we will openly condemn you for not acting like a responsible citizen”; (ii) (the unintended communication) “If you do behave as we ask, we will secretly condemn 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 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 moderate 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 feelings 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 themselves, and not even to their own interests, which might make sense, but to their anxieties” (18).
One does not have to be a professional psychiatrist to see the consequences 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 prohibition laws, but perhaps more effectively by the anxiety-generating mechanism 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 psychologically pathogenic. We hear much talk these days of responsible parenthood; the coupled words are incorporated into the titles of some organizations devoted 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 conscience? When we use the word responsibility 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.
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 arrangements.” Notice that Frankel calls for social arrangements--not propaganda.
Mutual Coercion Mutually Agreed upon
The social arrangements that produce responsibility are arrangements that create coercion, of some sort. Consider 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 freedom 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 Madison Avenue man might call this persuasion; 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 exposure to the light, by saying it over and over without apology or embarrassment. To many, the word coercion implies arbitrary decisions of distant and irresponsible 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 required 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 (grumblingly) 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 differences in individual inheritance, legal possession should be perfectly correlated 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 inheritance. 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 inheritance 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 contemplate. 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 reform measure is proposed it is often defeated when its opponents triumphantly discover a flaw in it. As Kingsley Davis has pointed out (21), worshippers of the status quo sometimes imply that no reform is possible without unanimous agreement, an implication contrary 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 status quo is action, we can then compare its discoverable advantages and disadvantages with the predicted advantages and disadvantages of the proposed 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 human 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 commons as a place for waste disposal would also have to be abandoned. Restrictions 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 mindless 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. Advertisers muddy the airwaves of radio and television and pollute the view of travelers. We are a long way from outlawing 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 commons involves the infringement of somebody’s personal liberty. Infringements made in the distant past are accepted because no contemporary complains of a loss. It is the newly proposed 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 became 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 necessity that we must now recognize, is the necessity of abandoning the commons in breeding. No technical solution can rescue us from the misery of overpopulation. 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 temptation must be resisted, because an appeal to independently acting consciences selects for the disappearance of all conscience in the long run, and an increase in anxiety in the short.
The only way we can preserve and nurture other and more precious freedoms 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 freedom to breed. Only so, can we put an end to this aspect of the tragedy of the commons.

Friday, July 05, 2019

The Human Face of Species Loss

The Dodo was just one of many....

The Human Face of Species Loss
By Peter McKenzie-Brown*

On October 31, 2011 I heard on the radio that, according to the United Nations, world population had just reached 7 billion. When I went online for details, I discovered Index Mundi – a data portal that turns facts and statistics into easy-to-use visuals. Since that day, the number of people on our planet has risen by another ten percent. It now increases by about 135 infants per minute. 
This vast and exponentially growing change in human population has fundamentally changed the biomass on our planet. Livestock (mostly cattle and pigs) now represent 60 per cent of the world’s mammals; people, 36 per cent; wild mammals, four per cent.
Over the last half-billion years, there have been five mass extinctions, when the diversity of life on Earth suddenly and dramatically contracted. Scientists around the world today are monitoring a possible sixth extinction, predicted to be the most devastating such event since an asteroid crashed into Earth some 66 million years ago. That episode – the fifth of the big five – famously wiped out the dinosaurs as it obliterated three-quarters of the plant and animal species in existence.

Birds and Citizen Science: This helps explain a dilemma facing humankind. As I suggested in a Critica commentary titled This is for the birds, I am one of a vast group of people around the world who get considerable satisfaction from birding – bird-watching to the uninitiated – and contributing in my small way to global databases about the health of our world’s avian populations.
For example, during the vast North American bird migration last spring, I was part of a group of 14 birders from Calgary who spent five days at Writing-On-Stone Provincial Park – so named because of ancient Indigenous carvings on local cliffs – to do five days of birding. The areas we explored were Milk River – little more than a creek in that area, which originates in Glacier National Park in Montana, flows northeast into Alberta, and then turns south and joins other streams running in that direction. Eventually, the waters from these many sources flow into the Mississippi.
We also enjoyed identifying other species. Of the mammals resident in that area we saw, for example, badgers and pronghorn antelope. Along the way, we stopped to see a prairie rattlesnake which had been killed by a car. As it turned out, another was nearby. This species is increasingly rare because of hunting and habitat fragmentation. To give the other rattler a better chance of survival, we chased it away from the road.
But the real purpose of our visit was to count the number of species present in a few well-defined regions near the border between Canada’s province of Alberta and the American state of Montana. We spent those days identifying species and counting the numbers of individual birds in each species in areas which had previous bird-count records. We then submitted detailed reports – a dozen of them in all – to Cornell University’s eBird website – a network the university launched in conjunction with the National Audubon Society in 2002.
This website accumulates and produces geographical data on birds throughout the year from around the world. Based in Ithaca, New York, Cornell also helps maintain a fleet of birdcams positioned to video active nests world-wide. This connects birders anywhere to nests around the world in which species – many of them rare or endangered – are hatching and raising their young.
Increasingly the centre of the ornithological world, eBird enables birders and ornithologists to record and enumerate bird populations from every habitat. Enthusiasts like our small band count birds within given geographical regions. Like others on our expedition, enthusiast Jennifer Solem was passionate about the value of these expeditions. “I feel bird counts may become very important for identifying the effects of floods and now, again, fires in crucial boreal breeding areas.” She was hopeful, she said, that the data emerging from bird counts could serve as “motivation for prioritizing conservation in [forest] habitat.”
For birds and other species, habitat is everything. For example, an ornithological study recently compared “blackbirds in Munich with their country cousins,” writes the notable author Diane Ackerman, reflecting a proposal from a group of scientists. In a recent book, she focused on the idea that we are entering a new geological epoch that should be called Anthropocene – a world created by humankind, which is profoundly affecting species that comfortably coexist with humankind. The city birds “adopt a faster pace, work longer hours, and rest and sleep less where upward-showering light washes out the stars and our handmade constellations cluster near the ground,” she wrote. “Urban males molt sooner, and reach sexual maturity faster.” By contrast, rural blackbirds “begin their day traditionally, at sunrise, don’t rush, and sleep longer.”[†]
Many other kinds of species have learned to co-exist in cities with people – deer, for example; cats, foxes, skunks, raccoons, houseflies, sparrows and mice are a few others. Rats exist in most of the world’s jurisdictions (although not in Alberta). Monkeys, of course, are city dwellers in many tropical countries.

Government Studies and Green Technologies: For ornithology as much as for the birds it studies, the issue is more serious in the densely populated places in the world than in the vast, sparsely populated provinces of Canada. Take the example of the Canada warbler – a bird that delights us for both its appearance and its song, but which is at risk. These warblers mostly breed within Canada’s boreal forest. They winter along the northern edge of South America, where avian diversity is more than fifty times greater than in North America’s boreal forests. The species is at risk in Alberta and other jurisdictions through such human actions as agricultural, urban and residential development and industrial activity. In Alberta, the activity in the energy sector is a threat, but so is timber cutting.
In Canada, efforts to save threatened species are failing. Of the more than 700 plants and animals currently listed under the Federal Government’s Species at Risk Act, most are losing ground at an alarming rate. According to World Wildlife Canada, on average those species have declined by another 28 per cent since the act came into effect in 2002. So, is being listed for federal protection a rescue operation or a recommendation to enter a ward for incurables?
The act requires the Canadian Government to protect listed species, but does not offer best practices on how to do so. Nor does it advise conservation groups on what to do when confronted with competing needs. With so many species in peril, and limited funds available, Canada’s conservation efforts to date look like a patchwork of measures guided as much by intuition and chance as by science.
Ironically enough, “green” technologies are actually contributing to the problem, according to a 2010 report from the US government. The use of wind turbines, for example, leads to death by collision with turbine rotors. On the positive side, “fatalities could be fewer because fewer larger turbines are needed to produce the same energy as smaller turbines.”
To put those numbers in perspective, the report observes that wind turbines kill between 214,000 and 368,000 birds annually. That’s frankly a small fraction compared with the estimated 6.8 million fatalities from collisions with cell and radio towers and the 1.4 billion to 3.7 billion deaths from domestic and feral cats.
Of course, the problem of species death is not only about birds. Consider the situation of the only known flying mammals: bats. Like birds, these creatures tend to be migratory. “Bat fatalities peak at wind facilities during the late summer and early fall migration,” according to government report. “Bats are long-lived and have low reproductive rates, making populations susceptible to localized extinction.” Some researchers believe “bat populations may not be able to withstand the existing rate of wind turbine fatalities and/or increased fatalities as the wind industry continues to grow.”

A Global View: Internationally, one in every eight bird species faces possible extinction, according to a riveting recent report by Birdlife International. Calling bird life “nature at its most enthralling,” the report describes birds as “one of the best known and most highly valued elements of the natural world.” They comprise more than eleven thousand different species, “ranging from hummingbirds to ostriches, from penguins to eagles.” Each species is unique in appearance, habits and habitat requirements. Some still occur in vast flocks, while others are now down to a few remaining individuals. Some spend their entire lives within a few hectares of land. Others undertake annual migrations that cover half the world.
Most birds that people value are not at risk. A couple of dozen species and subspecies have economic value as food and for feathers. They range from geese to domesticated chickens. Birds also have some surprising uses. Also, of course, such species as parakeets and cockatoos are often sold as pets. However, many of their wild populations are declining due to capture for the pet trade.
Other highly prized birds are at risk, of course. For example, in Southeast Asia, swiftlet nests – constructed almost entirely of saliva, with little or no plant material – are used to prepare a highly prized soup consumed by men who believe it is an aphrodisiac. “It's the caviar of the East,” a Hong Kong restaurateur told The New York Times in 1996. “Some economists and conservationists see the pressure on edible bird nests as a symptom of a much deeper problem in East Asia,” the newspaper added. “Rapid economic expansion, population growth and industrialization have created unsustainable demands on natural resources.”
With those bits of knowledge under my hat, I drove down with the expedition’s de facto organizer, long-time friend Dave Russum. We talked about the not-too-obvious reality that the days are now long gone when you were likely to drive along rural roads and find your windshield covered with the remains of insects.
A geologist by training, Dave reminded me that “the first insects on Earth evolved about 400 million years ago while birds, as we know them, first evolved about 60 million years ago. Insects were therefore well established around the globe when birds showed up.” For many bird species, they were an obvious food source. He added that most species need insect protein to successfully rear their young, but can use fruit in their diet for the rest of the year.
Such species as swallows and flycatchers, however, “are dependent on insects for most of their nourishment, not just on their breeding grounds and wintering grounds, but also during their migration in the spring and fall.” If natural habitat and the associated insects are destroyed over a significant area, many of the birds dependent on those insects cannot survive. “Their populations will rapidly decline.”
I reflected on that a bit. When I left Toronto for Calgary in the 1970s, the car that reached this city was a mess, with splattered bugs covering the windshield and grill. I can’t recall when I last noticed such a thing, even after a long drive into rural Alberta. The reason is that the absolute number of insects (not species) on our planet is in rapid decline, from Arctic to Antarctic, and virtually everywhere in between.
There are so many fewer insects in the system because of human causes. These include urbanization, intensive agriculture and, to some degree, the use of pesticides. But in addition to the lost numbers of insects, some 40 per cent of insect species face out-and-out extinction.

Extinctions: Perhaps one of the greatest causes of decline in insect numbers is the use of electric lights. We have long known that night-flying insects are attracted to a candle. Night-flying insects probably outnumber day-flying ones, ten to one.
Most insects spend a lengthy period as eggs, larvae and pupae before emerging as adults – but then they have only a few days to find a mate and lay eggs, to pass life on to the next generation. When they emerge as adults, they are now attracted to street and porch lights, etc., where they fly around all night. In the morning, exhausted, they cling to those lights, posts or building.
Birds have been quick to find this bonanza of insects. First thing in the morning, they now head for the light source. They can glean the same amount of food within a few minutes, which in the past might have taken most of the day. However, in consuming these newly-emerged adult insects, they are eliminating the source of food – insect larvae – that they need to feed their own young when they hatch. Most of those nestlings are now starving to death. And when the adults die, without any replacement, that bird species becomes extirpated or goes extinct.
The greatest declines in insectivorous birds in North America are in the most densely populated areas – in particular, the eastern provinces and U.S. states.
You almost certainly know about the virtual extinction of bison from North America’s prairies in the nineteenth century, the total extinction of vast herds of passenger pigeons about the same time. Less well known is that the Rocky Mountain locusts once blotted out the sun over the Great Plains. In the summer of 1875, for example, an estimated 10 billion of these insects took nearly a week to pass through Plattsmouth, Nebraska. Twenty-seven years later, the last living specimens were collected on the Canadian prairie. Their extinction was a huge blow to North America’s ecosystems, since they had provided food for countless insectivores.
Why is that important? Animals, mostly insects, pollinate 87% of flowering plants, observes a commentary in The Economist. “Without insects, most plants could not reproduce. They also break down and recycle the nutrients that plants need for photosynthesis. They decompose organic waste and feed a large proportion of all birds and bats.” If plants don’t reproduce, they disappear – taking with them the nectar and pollen sources that insects need.
In terms of the number of species, insects are by far the most abundant life forms. They are so numerous that they contain three times as much mass as humans and 30 times that of all wild mammals. There are more than one million insect species (perhaps as many as thirty million), compared to some 6,000 varieties of mammal, and 18,000 species and subspecies of bird.
Insects live in almost every habitat on the planet – on all seven continents, in lakes and rivers, seas and oceans, sloughs and deserts. And they are vital contributors to the food chain everywhere. Mammals, birds, fish, reptiles and insects themselves can all be wholly or partly insectivores. The rapid decline in these food sources is contributing to rapid declines in other species of many types. And that brings me back to the likelihood of yet another mass extinction.

Sixth Extinction? Five vast extinctions – called “the big five” by earth scientists – have challenged life on Earth during the past 500 million years. The best known of these was a sudden mass extinction of some three-quarters of the plant and animal species approximately 66 million years ago – famously killing off the dinosaurs, but also many other species. It marked the end of the Cretaceous period and with it, the entire Mesozoic Era, opening the Cenozoic Era we are in today.
A recent United Nations report titled 2019 Global Assessment Report on Biodiversity and Ecosystem Services suggests that we are now at the beginning of a sixth. For three years, hundreds of scientists contributed to the project. They concluded that as many as a million species planet-wide may be on the brink of extinction.
The UN study of this problem would certainly have considered the content of a 2014 book by Elizabeth Kolbert. The author tells us why and how human beings have altered life on the planet in a way no species has before. Interweaving research in half a dozen disciplines, descriptions of the species that have already been lost, and the history of extinction as a concept, Kolbert provides a moving and comprehensive account of the disappearances occurring before our eyes.[‡]
“In what seems like a fantastic coincidence, but is probably no coincidence at all,” she writes, “the history of these events is recovered just as people come to realize they are causing another one.” She suggests that the sixth extinction is likely to be mankind's most lasting legacy to our planet, “compelling us to rethink the fundamental question of what it means to be human.” We are affecting planetary systems in many ways, and have been doing so every moment for centuries.
Citing a paper in which researchers from McGill University and the University of Maryland describe the world’s “anthromes” (also known as anthropogenic biomes or human biomes), she notes that these the globally significant ecological patterns reflect sustained interactions between people and the world’s ecosystems. Once you add up the total area covered by these systems, there are only 28.5 million square kilometres (11 million square miles) of space left on the planet. “These areas, which are mostly empty of people and include stretches of the Amazon, much of Siberia and northern Canada, the Sahara, the Gobi and the Great Victoria deserts, they call the ‘wildlands.’”
It is certain that “something big” is underway, she says. The best estimates are that Earth is losing species at many times the background rate – the natural churn in which a few species go extinct every year while new ones evolve. Between 30 percent and 50 percent will be functionally extinct by 2050. “Right now,” humankind “is deciding, without quite meaning to, which evolutionary pathways will remain open and which will forever be closed,” she wrote. “No other creature has ever managed this, and it will, unfortunately, be our most enduring legacy.”
Perhaps the best way to conclude this discussion is with quotes from two renowned scientists, whom Ms. Kolbert notes in her closing pages. “Homo sapiens might not only be the agent of the sixth extinction,” said renowned anthropologist Richard Leakey. Our species “also risks being one of its victims.”
Stanford ecologist Paul Erlich agreed. “In pushing other species to extinction,” he wrote, “humanity is busy sawing off the limb on which it perches.”

[*] Thanks to Gus Yaki for his comments on a draft of this document. In early 2019, the Governor General (Canada’s head of state, who represents the Queen) conferred upon him the Sovereign's Medal for Volunteers for his efforts on behalf of natural species. 
[†] Ackerman D. The human age: The world shaped by us. HarperCollins Publishers Ltd.; 2014; 114.
[‡] Kolbert E. The sixth extinction: An unnatural history. A&C Black; 2014.