Environmental problems are, roughly, of two sorts: concrete, palable, fairly well known, and related primarily to the present; or abstract, unfamiliar, rather badly known, and related primarily to the future. Pollution is mainly of the first sort. Much of it can be seen, smelled, and tasted right now. Given minimal environmental awareness, public pressure is high to lower its incidence and impact. Resource depletion, soil and water depravation and climatic change are of the second sort. Public pressure to diminish the environmental risks associated with these problems cannot be expected from reactions to direct impacts but only from the persistence of a high level of future-oriented environmental concern and an educational and political system supporting it. Environmental politics in regard to problems of the first sort is mainly a matter of enlightened self-interest. Environmental politics in regard to problems of the latter sort is unthinkable without an essentially ethical basis.

I wish to address myself to one prominent long term environmental problem, the problem of long term climate change by the emission of carbon dioxide and other greenhouse gases: Are there ethical reasons for the European countries to contribute effectively to the prevention of imminent climatic catastrophe? No doubt, there is a presumption for assuming preventive responsibility following from the polluter pays principle: The European countries contribute a substantial percentage of the global emission of carbon dioxide by the burning of fossil fuels. Nevertheless, responsibility of the European countries - and of the industrialised world generally - to reduce CO2 emission is sometimes denied by appealing to one or other of three arguments:

1. The potential impacts of the greenhouse effect will affect generations in a distant future. The time horizon of moral responsibility, however, is limited to the generations of our children and grandchildren.
2. The potential impacts will mainly affect developing countries. Responsibility for their destiny is primarily in the hands of these countries and their governments. Moreover, the scope for preventive strategies is severely limited. Adaptation strategies are to be preferred that limit the potential impacts of the climatic changes on vegetation, agriculture and society. These are best undertaken by the affected countries themselves.
3. The climatic effects and especially their possible secondary and tertiary impacts are too uncertain to justify preventive measures, especially if these imply that chances of economic reconstruction and development will have to be forgone.

Arguments of this kind have a strong psychological appeal. If they were valid they would take some of the weight of long term environmental responsibility from our shoulders. In the case of the climatic problem this weight is especially heavy. The predicted environmental damage is more or less abstract, psychologically, whereas shouldering it might mean giving up, to a certain extent, highly valued freedoms such as the freedom of unlimited car driving.

How convincing are these three arguments from an ethical viewpoint?

As an ethical argument, the existence or non-existence of inter-generational sympathies is of doubtful relevance, however. Moral obligations generally extend further than emotional ties. Although "Pflicht" and "Neigung" should not be seen to stand in too strict an opposition, it is nevertheless part of the point of moral norms and attitudes to function as substitutes and extensions of natural sympathies and natural altruistic impulses. Positive moral obligations of solidarity generally reach beyond personal relations, negative moral obligations of prevention extend to potential victims independently of whether they are known or identified in advance. The same applies to future victims of present acts or omissions. They are even in a worse plight than present victims since they cannot even voice their protest against what they are made to suffer. They have to rely on prior advocacy of their interests.

Discounting future victims because they are future cannot be morally justified since it is in plain contradiction with the "moral point of view". The universality and impartiality inherent in the moral stance does not stop short of the temporal dimension. Privileging the present is clearly an act of morally doubtful partiality, an act of generational nepotism. The economic practice of discounting, on the other hand, is certainly valid in principle, but it is far from obvious how it applies to the present problem. Even if it is granted that social and personal harm can in principle be measured by monetary equivalents, it must be remembered that discounting future monetary values works on the assumption that the real rate of interest over the period considered will be positive. This assumption, however, is highly questionable for those countries that are expected to suffer most from the impending climate change, e.g. Bangla Desh and the countries in the Sahel zone. Their economic prospects are far from good.

Perhaps this point of view will seem overly moralistic. It might be said that it is not enough for ethics to make pious appeals, but that there must be sanctions of some kind or other to go with it if it is to become effective. This objection can be answered. Practical morality does indeed depend an sanctions. But it would be wrong to think that there can be no sanctions for obligations towards people who are far way temporally, geographically and culturally. Sanctions exist even now, both internal and external. The efforts to integrate concern for the environment into the agenda of the educational system has undoubtedly had its effect on the younger generation. The environment has become one of the central topics both of interest and concern. With the usual time lag, social pressures have begun to build up sanctioning grossly "unecological" behaviour such as dumping waste, using greenhousegas-emitting sprays and driving "dirty" cars. The most powerful sanction, as far as the global environment is concerned, is the external sanction of the pressure of global migration from South to North which has already started on a large scale and is likely to increase with growing population and continuing environmental destruction in the Third World. The fact that the social and psychological capacity to absorb refugees from other civilisations has already reached its limit in some parts of Europe, and the prospect that this might only be the beginning of a period of growing pressure on Europeans to open their borders for people of the South, promises to be a convincing reason not to intensify the impending global conflict by additional environmental destruction even for the moral chauvinist.

1. Proponents of the first argument usually draw on two considerations to "discount" present responsibility for future generations: the temporal limitation of sympathies and the economic practice of discounting future positive and negative values. First, relations of sympathy extend to our children and grandchildren, but hardly further. They do not extend to abstract future generations with unknown and possibly quite foreign values and life-styles. Second, to the extent that future harms and benefits can be assigned monetary values they should be discounted to present value in the same way as future income. Thus, given a positive rate of interest, the present disvalue of future harms will be substantially lower that at their respective time of incidence.
2. Concerning the second argument it should be conceded that, of course, moral responsibility for the destiny of a country rests primarily with its own government. There is an obvious pragmatic point in distributing moral responsibily in such a way that obligations have a fair chance to be effectively met, and this chance is greatest where the psychological costs of conformity are low, as with obligations to securing the well-being of those who are next to one's heart anyway. This pragmatic consideration loses much of its ethical force, however, whenever the capacity of the countries concerned to make provisions for their future populations is severely limited. Even if the European countries were not in any way causally responsible for the environmental changes that threaten some of the developing countries, there would nevertheless be some point in making them morally responsible, since moral responsibility does not, in general, depend on factual causality, i.e. on prior intervention, but on potential causality, i. e. on the capacity to intervene. As matters stand, however, the obligation of the industrialised world to prevent environmental disasters of an unprecendented scale for some of the poorest countries of the world is not just an obligation of beneficence, but an obligation of justice. The risks in question are neither natural nor self-imposed, but clearly the result of the dysfunctional life-style of the industrialized countries, with a level of energy consumption incompatible with the idea of sustainable development for all. In a few decades it probably will seem as luxurious, irresponsible and pointless as the life-style of baroque aristocrats seems to many of us today.
3. The degree of certainty to be attained in global environmental forecasting is notoriously limited. This is particularly true of the global climatic problem. Even fundamental questions such as whether the observed changes in temperature are anthropogenic in origin continue to be controversial. Even if there were complete certainty about the prospects for the climatic system there would still be a great deal of debate over their secondary and tertiary effects.

But of course, uncertainty about the potentially destructive effects of one's actions or omissions is not by itself a moral excuse. It is an excuse only if

• the potentially destructive effects can easily be prevented once a better and more securely founded estimate of their dimensions and their probability becomes available, and
• living with the threat of future damage is acceptable psychologically.

It may be doubted whether these conditions obtain in the present context. However divided over questions of detail, the experts are agreed that once the climatic effects have come about, they will be irreversible. So will be their presumed secondary effects, the destruction of vegetations and soils. Even worse, in view of the time-lag with which climatic effects become manifest it cannot be excluded that the process might already be irreversible when the first conclusive evidence becomes available that it is actually going on. Potential or probable irreversibility of harmful effects is, however, a strong reason for the risk-aversive strategy of "playing safe". This can only mean that the emission of carbon dioxide and other greenhouse gases should be reduced by a substantial amount and at short notice, even at the cost of temporary setbacks in economic reconstruction and development. The same conclusion follows from the second consideration. One of the characteristic psychological asymmetries between chances and risks is the amount of attention and emotion they are likely to evoke, given an acceptable level of material well-being. Normally, people are more willing to pay for a significant reduction of risks than for a significant increase of chances. Observations in the field of buying insurance provide evidence for a high preference for safety and a relatively low preference for risk. The fear associated with the threat of damage is rarely equalled by the thrill of "living dangerously". Analogously, feeling assured that an otherwise threatening climatic change will not come about is a vastly more important value than the opportunity to verify which of the present climatological prognoses comes nearest to the truth. Not only the avoidance a potential damage is a positive value, but also the assurance that it can and will be avoided.

It must, however, be remembered that the value of safety, and especially of long-term safety, is dependent on the general level of welfare. The safety of future generations cannot mean much to a man who does not know how to get his children fed for the day. It means more to the average European than to the average African or Indian. The European cannot seriously expect that his own risk-averse strategy will be followed by those on a significantly lower level of material well-being. The thought that he will be alone, for some time, in keeping the initiative, should not detract him, however, from taking it. Without him taking the lead, the prospects are even worse.

It is not the job of the ethicist to make concrete political proposals. But let me at least express my conviction that the present policies of reducing the emission of carbon dioxides and other greenhouse gases, however laudable, are too half-hearted to inspire confidence. What seems to be especially called for, both for long-term and for short-term environmental and safety reasons, is a significant reduction in car traffic, above all in the large cities and conurbations where traffic has taken the place of industry as the main source of low environmental quality. Paradoxically, politicians continue to be a good deal less environmentally minded that their constituencies, obviously under-rating the preparedness of their voters to support, from prudential as well as from ehtical reasons, allegedly "unpopular" environmental policies.

Dieter BIRNBACHER, Priv.- Doz., Dr., Ak. Rat
University of Essen, Germany