(From The Year 2000 A Framework for Speculation on the Next Thirty-Three Years By Herman Kahn and Anthony J. Wiener with contributions from other staff members of the Hudson Institute, Introduction by Daniel Bell , The Macmillan Company, New York, N.Y. Collier-Macmillan Limited, London, 1967, pp. 262-264; © Hudson Institute)
(…) Scenarios are attempts to describe in some detail a hypothetical sequence of events that could lead plausibly to the situation envisaged. Some scenarios may explore and emphasize an element of a larger problem, such as a crisis or other event that could lead to war, the process of "escalation" of a small war or local violence into a larger war, the spread or contraction of a limited war, the fighting of a war, the termination of the war, or the subsequent peace. The focus of such a scenario can be military events and activities, the internal dynamics of various countries, bargaining among enemies or inter-ally relations, and so on. Other scenarios can be used to produce, perhaps in impressionistic tones, the future development of the world as a whole, a culture, a nation, or some group or class. The scenario is particularly suited to dealing with events taken together—integrating several aspects of a situation more or less simultaneously. By the use of a relatively extensive scenario, the analyst may be able to get a feeling for events and the branching points dependent upon critical choices. These branches can then be explored more or less systematically or the scenario itself can be used as a context for discussion.
(1) They serve to call attention, sometimes dramatically and persuasively, to the larger range of possibilities that must be considered in the analysis of the future. They are one of the most effective tools in lessening the "carry-over" thinking that is likely even when it is clear to all that 2000 cannot be the same as 1965 or even 1985. Scenarios are one way to force oneself and others to plunge into the unfamiliar and rapidly changing world of the present and the future:
(2) They dramatize and illustrate the possibilities they focus on in a very useful way. (They may do little or nothing for the possibilities they do not focus on.)
(3) They force the analyst to deal with details and dynamics that he might easily avoid treating if he restricted himself to abstract considerations. Typically no particular set of the many possible sets of details and dynamics seems especially worth treating, so none are treated, even though a detailed investigation of even a few arbitrarily chosen cases can be most helpful.
(4) They help to illuminate the interaction of psychological, social, economic, cultural, political, and military factors, including the influence of individual political personalities upon what otherwise might be abstract considerations, and they do so in a form that permits the comprehension of many such interacting elements at once.
(5) They can illustrate forcefully, sometimes in oversimplified fashion, certain principles, issues, or questions that might be ignored or lost if one insisted on taking examples only from the complex and controversial real world.
(6) They may also be used to consider alternative possible outcomes of certain real past and present events, such as Suez, Lebanon, Laos, or Berlin.
(7) They can be used as artificial "case histories" and "historical anecdotes" to make up to some degree for the paucity of actual examples.
While the conscious use of scenarios has become widespread, it has also been criticized. One criticism is that only a "paranoid" personality, unjustifiably distrustful, suspicious, and preoccupied with hostility, could conceive of the kind of crises, provocations, aggressions, and plots that characterize many politico-military scenarios. Unfortunately this characterization seems to have more to do with the kinds of politico-military events the real world provides and planners must prepare for than with the psycho-dynamics of the planner. His responsibilities require him to be most interested in the many unpleasant ways in which things can go wrong; he should also be interested in what can go right, but the latter tends to be both or as a "named" possibility that can be referred to for various purposes. Some of the advantages of the scenario as an aid to thinking are more difficult and usually less useful to explore by means of scenarios. Of course, any particular scenario may in fact contain paranoid ideas, but this must be judged on the basis of the plausibility of the particular scenario— often a difficult judgment in a world of many surprises—and care must be taken to allow for a possibly realistic inclusion of a not-implausible degree of paranoia in one or more decision-makers who have roles in the scenario.
A second criticism is that scenarios may be so divorced from reality as not only to be useless but also misleading, and therefore dangerous. However, one must remember that the scenario is not used as a predictive device. The analyst is dealing with the unknown and to some degree unknowable future. In many specific cases it is hard to see how critics can be so certain there is a sure divorce from a reality that is not yet known and may present surprises. Imagination has always been one of the principal means for dealing in various ways with the future, and the scenario is simply one of many devices useful in stimulating and disciplining the imagination. To the extent that particular scenarios may be divorced from reality, the proper criticism would seem to be of particular scenarios rather than of the method. And of course unrealistic scenarios are often useful aids to discussion, if only to point out that the particular possibilities are unrealistic.
It is also worth noting that for some purposes mistakes in particulars may be of secondary importance. (…) However, if a scenario is to seem plausible to analysts and/or policy-makers it must, of course, relate at the outset to some reasonable version of the present, and must correspond throughout to the way analysts and/or policy-makers are likely to believe decision-makers and others are likely to behave. Since plausibility is a great virtue in a scenario, one should, subject to other considerations, try to achieve it. But it is important not to limit oneself to the most plausible, conventional, or probable situations and behavior. History is likely to write scenarios that most observers would find implausible not only prospectively but sometimes, even, in retrospect. Many sequences of events seem plausible now only because they have actually occurred; a man who knew no history might not believe any. Future events may not be drawn from the restricted list of those we have learned are possible; we should expect to go on being surprised.