26 Journal of Behavioral Decision Making Vol. 2 Iss. No. 1
present. When people consider an event that has not yet occurred, they adopt a forward perspective. If
they look back in time to a concluded event, they adopt a backward perspective.
It is natural that past and future events are usually treated differently. Normally people explain the
past and predict the future. Looking back at events that have already occurred, the critical question is
"why.' Looking forward into the future, the question is more often 'what (will happen).' The two
questions are related. One generally hopes to learn from explaining the past and to apply this
knowledge to predicting the future. It is clear that the better one can anticipate future events, the more
successful decisions and actions can be.
Although only the backward perspective is normally associated with explanation, suppose that
people shifted their perspective on future events to think about them as if they had already occurred.
Why might they do this? People can make better decisions about a future course of action if they fully
understand all that is required to make it happen, including the perhaps-not-so-obvious. Weick (1979),
Hogarth (1983) and others have suggested that traveling forward in time to look backward on a future
event might improve decision making, by helping people see more of these necessary ingredients.
though never directly tested, stems in part from studies showing that temporal perspective
can influence the way people perceive and evaluate events. How subjects described past and future
events differed in terms of amout of detail, causal complexity (as measured by description length), and
level of abstraction (Bavelas, 1973; Sevon, 1984). In these studies, subjects described past events in more
details and at greater length than they did future events.
Explaining future events as past (i.e., prospective hindsight) might well improve decision making if
people do 'see' more when they look backward. Given this potential value, prospective hindsight
deserves further investigation. However, to understand this phenomenon it is important to control for a
natural confounding factor, uncertainty of outcome.
Uncertainty and explanation
In previous temporal perspective studies, future events were always presented to subjects as uncertain,
and past events always had sure outcomes. For instance, Sevon (1984) concluded that decision makers'
conceptions of past events were more causally complex then their conceptions of identical future events.
However, her experimental task compared explanations for Sweden's past high inflation/unemploy-
ment with explanations for possible but uncertain high inflation/unemployment in a future period.
Although such a comparison legitimately reflects real world conditions, it is not possible to know
whether the observed effects were due to differences in temporal perspective or to the accompanying
differences in uncertainty. Other studies also suggest that uncertainty contributes to the inferences
people make about events. For example, in the 'sealed-fate effect' subjects bet less when dice are thrown
but not yet revealed, than when dice are thrown after bets are placed (Strickland, Lewicki, and Katz,
Rothbart and Snyder, 1970).
This leads us to ask: What is the role of uncertainty in accounting for the differences in explaining
events, that have heretofore been attributed to temporal perspective? The most extreme hypothesis is
that the entire effect of temporal perspective is due to uncertainty. It is uncertainty that is 'driving' the
observed differences in explanation, and the natural confounding between these two contextual factors
has led to a misattribution of these effects to temporal perspective. At the least, it would be useful to
disentangle the two factors and assess the independent impact of each.
If certainty of outcome does influence how subjects perform an explanation task, how might this
happen? Subjects might work at explaining an event either longer (an effort hypothesis) or differently (a
processing hypothesis). The effort hypothesis presumes that subjects devote more time and, thereby,
explain more thoroughly a sure event than an uncertain one. Possibly people feel more obligated to
explain a known outcome than to waste time constructing an explanation for an outcome that may or
may not occur. In contrast, the processing hypothesis asserts that uncertainty influences the cognitive