For millennia, humans from diverse cultures have used oracles and omens to try to read the future. Science and mathematics have long contributed to this effort, originally through astronomy but now by supercomputers allied to theories and datasets. For a while, the universe was likened to an enormous mechanical clock, and a conceit arose that with sufficient data, theory, and computational power, science might one day refine predicting human affairs to a high accuracy. More recent discoveries of relativity, quantum mechanics, and chaos theory show the fallacy of this thinking, even challenging precise astronomic forecasts.
Postmodernism has questioned other fundamentals, so that definitive statements about even the present can seem audacious. However, the quest for the perfect should not obstruct the search of the helpful. The failure to develop a widely accepted science of history does not negate the existence of useful and durable historical principles; the fact that the future can never be known with certainty does not mean that little of value can be said about it.
The futurist and systems thinker Hartmut Bossel has usefully likened the range of future possibilities as constrained within ‘‘riverbeds’’ of likelihood. Many properties of human and natural systems compose these riverbanks. As well as the laws and principles of physics, genetics, biology, evolution etc, perhaps the most fundamental determinant of the future is that it must evolve from the present. This means not only that future human society will be strongly influenced by current and recent economic and social trends and theories, but also that past alliances, injustices, resentments, and enmity cannot be wished away. Historical facts, transmitted in the culture and contained within the psychology and memory of billions of people, will inevitably influence the future. There are a myriad of such facts and memories, and together they act to significantly restrict the range of possible futures.
Similarly, existing institutions—social conventions, interpersonal networks, rules, agencies of government, markets, laws, and norms—are embedded in the memory, customs, and behavior of the 7.2 billion souls currently alive. Institutions change, but their rate of change is slowed by the complex conceptual, legal, and psychological elements through which change must be filtered. Other identifiable riverbed components include demographic and infrastructural inertia and the plausible rate of technologic evolution. For example, barring calamity, such as nuclear war or an asteroid impact, the human population in 2020 will inevitably be larger than 7.5 billion. Similarly, there are maximal rates of technologic transition, such as the development and diffusion of a solar- and hydrogen-fueled energy system that cannot be plausibly exceeded. Though daunting, the generation of plausible futures is not impossible, and many spheres of science—especially physical, ecologic, and social—have made and will continue to make important contributions to this developing field. Perhaps one day scientific disciplines of both the future and history will be mature and respected.
All humans build scenarios and create mental models of the future. We all know that the sun will rise tomorrow, and we project many other elements of the present into the short-term future, such our plans for a holiday or even retirement. But as the length of focus and the variety of possible outcomes increase, confidence we can have in our projections diminishes rapidly.
Some futurists imagine a world of extremely rapid technological innovation and transformation. It is possible to conceive of a future full of energy- and greenhouse gas emission–sparing devices, of new crops that reduce cultivation pressure on marginal land, of techniques that harness biology to large-scale industrial processes, and of new forms of communication that enable the rapid diffusion of information, literacy, and education. Such visions can then be used to forecast optimistic rates of hunger alleviation, of slowed greenhouse gas accumulation, of adequate water quantity and quality, and so on.
Lay scenarios and social thresholds
Planning, whether for the next hunt, crop or corporate takeover, is an ancient human characteristic and has often formed the basis for attempts to enlist celestial help. In well-governed societies, sophisticated economic and social planning is routine. As large as the formal scenario literature is, an even larger mass of lay scenarios exists within people's imagination. The collective imagination of the near-term future by large numbers of people can sometimes mobilize society in ways that significantly influence that future, such as by large-scale protests and revolution.
In some cases, social thresholds are passed that are beneficial to society, freedom, and population health. For example, the peace movements in Western countries in the 1980s arose in part because millions of ordinary people became sufficiently concerned about a potential nuclear Armageddon (a lay scenario) to vehemently protest. In turn, this reduced the risk of global nuclear war. Shortly after, mass social movements in Eastern Europe led to the peaceful fall of several governments.
In other cases, such as the 1989 Tiananmen Square protest in Beijing, collective imagination proved, premature. The Rwandan genocide of 1994, when one-sixth of the country’s population was rapidly slaughtered, illustrates the passing of a social threshold that was immensely damaging to population health. Although this event may seem an inexplicable example of barbarity, other workers have suggested that the genocide was in fact a foreseeable and understandable consequence of resentment and resource scarcity leavened by the rapid growth in the number of largely unemployed, landless, manipulable, and desperate young men.
Problems with existing scenarios
Large-scale thresholds, whether social or environmental, are problems for scenario maker. These thresholds that lead to the quantitatively and qualitatively altered post-threshold states are hard to predict. Though their nature is uncertain and contested, their occurrence is well understood, not only by scenario workers, but also by the lay public. Evidence for this exists in the plethora of sayings in many languages and cultures, such as ‘‘a chain is only as strong as its weakest link’’ and ‘‘it is the last straw that breaks the camel’s back.’’
Most scenario builders work in groups, and reaching a consensus about the scale and timing of thresholds introduces another difficulty. This may be complicated by a wish to not appear too negative, because of the risk of marginalization of more pessimistic forecasts, such as the Limits to Growth or those from Lester Brown.
The precise prediction of most thresholds (other than their general existence) will almost always be wrong, and this may thus be seen as reducing the credibility of scenario theory. Thus there may be a tendency for most scenarios, especially those developed by groups, to understate their frequency and severity. Thresholds are also problematic for quantitative modelers, who can still rarely factor thresholds into their models. Imagine, for example, the political difficulty of introducing an equation that specifies a population-reducing calamity such as a civil war once population density, poverty, and inequality exceed thresholds.
But, excluding such factors can produce implausibly optimistic scenarios. For example, the United Nations Population Division has long provided forecasts of the global population based only on demographic factors such as birthrates and average life expectancy. The possibility of large-scale war is entirely absent from consideration, and has led to absurdly high projections of maximum global population. Although more recent UN population projections have been lowered in response to the scale of the HIV epidemic, their projections continue to assume, implausibly, an absence of other adverse threshold events.
In other cases, the inability to factor in positive social thresholds may lead to excessively pessimistic scenarios. One such pessimistic scenario posits the almost complete loss of civil society, especially in developing countries, thus leading to ‘‘barbarisation’’. Countering forces are likely to sequester such outbreaks, though with local spread, for example to Syria and Iraq, Congo and South Sudan... but not yet to Hawaii and Edinburgh.
Most scenario framers claim their visions are equally plausible, actually they are equally implausible. Exaggerating existing tendencies to reveal clearly distinct futures is makes such futures unlikely; a blend of various scenarios is far more likely, but more messy and harder to sell. Most scenarios are caricatures that will not occur on a global scale. Most scenarios are biased toward optimism and the privileging of Western values, and understate the risk of adverse social and environmental thresholds. Despite their limitations, scenarios can still be of value. The imagination of alternative futures can provide insight into policy formulation. The visualisation of adverse consequences may influence preventive policies. Desirable scenarios may inspire decision makers to work constructively.
Governments, corporations, and defense organizations will continue to explore diverse scenarios. Adding social, environmental, climatic, ecologic, and health aspects to the scenario literature can only help. More place is warranted for desirable scenarios. Scenario workers could then work backward from this imagined future to the present to see how it might be achieved. The wide involvement of civil society in the process of imagining such a future (though not one that is utopian) could be useful.
Global social affairs are enormous juggernaut, beyond control and operating in a competitive global market on a planet with limited resources and a human population that may be beginning to realize its collective footprint and, perhaps, its collective responsibility. Although ideally we will look before we leap, ‘‘he who hesitates is lost’’ may reflect the competitive pressure that most people work with. These competitive forces constrain the power of decision makers to influence the future.
The global environmental system has tremendous inertial and self-organizational properties. Although humans have long influenced the global environment, it is hubristic to think geo-engineering or other strategies will radically and beneficially alter this environment within a few generations. At best, our influence will probably be painfully limited, although a small contribution could still prove very valuable, given that we do not yet know the full biosocial capacity of the planet.
Workers in health, ecology, and other fields related to sustainability can collectively make a crucial contribution. This is to challenge the view that limits are neither real nor close. The excessively optimistic counterview, found especially in some economic and demographic literature, has been characterized as one that ‘‘lays stress on new ideas as a source of progress, supposing that the growth of ideas is capable of circumventing any constraint the natural-resource base may impose on the ability of economies to grow indefinitely’’ (Dasgupta, 2000).
This counterview is powerful in the worldview of many currently influential people. Taken to extremes, it is a kind of magical thinking. Alan Greenspan proclaimed faith in the capacity of the market to generate solutions to the current high cost of oil. I too have some faith in the capacity of society to solve its problems, as does Dasgupta. However, left to the market alone, such solutions are likely to be at a high social cost.
Technology is not the only crucial element for the future, including for health. The quality of our institutions, culture, aspirations, rules, norms, and resource distribution is of at least equal importance. Science needs to contribute to both. Peering into the fog, it is still possible to discern a future better than the present, but it will take much hard work, the change of some fundamental values, and, probably, a good measure of luck.
Dasgupta P (2000) Population and resources: an exploration of reproductive and environmental externalities.