Increasing Returns,Path Dependence,and the Study of Politics June 2000 Rather than simply apply extant arguments in econom- we cannot understand the significance of a particular ics to political phenomena,we need to consider the social variable without understanding "how it got features of the political world that require modifica- there"-the path it took.Previous events in a sequence tions in the use of path dependence claims.I will influence outcomes and trajectories but not necessarily demonstrate that increasing returns arguments are at by inducing further movement in the same direction. least as relevant to an understanding of politics as they Indeed,the path may matter precisely because it tends are in other areas of the social sciences.Indeed,factors to provoke a reaction in some other direction. such as the prominence of collective activity in politics, An alternative,narrower definition has been sug- the central role of formal,change-resistant institutions, gested by Margaret Levi (1997,28): the possibilities for employing political authority to magnify power asymmetries,and the great ambiguity of Path dependence has to mean,if it is to mean anything. many political processes and outcomes make this a that once a country or region has started down a track,the costs of reversal are very high.There will be other choice domain of social life that is especially prone to increas- points,but the entrenchments of certain institutional ing returns processes. arrangements obstruct an easy reversal of the initial The final section considers what these arguments can choice.Perhaps the better metaphor is a tree,rather than contribute to political analysis.They provide an impor- a path.From the same trunk,there are many different tant caution against a too easy conclusion of the branches and smaller branches.Although it is possible to inevitability,"naturalness,"or functionality of observed turn around or to clamber from one to the other-and outcomes.Given the ubiquity of claims about efficient essential if the chosen branch dies-the branch on which a or functional elements in politics,this alone would be climber begins is the one she tends to follow. an important corrective.More significant,increasing This conception of path dependence,in which preced returns arguments justify efforts to stretch the temporal ing steps in a particular direction induce further move- horizons of political analysis.They can redirect the questions political scientists ask,which will contribute ment in the same direction,is well captured by the idea of increasing returns.In an increasing returns process, to a richer appreciation of the centrality of historical the probability of further steps along the same path processes in generating variation in political life.They increases with each move down that path.This is can also direct attention toward particular variables because the relative benefits of the current activity and suggest promising hypotheses about the sources of compared with other possible options increase over both political stability and political change in certain time.To put it a different way,the costs of exit-of common political settings.For instance,increasing switching to some previously plausible alternative- returns arguments highlight the need to consider hy- rise.Increasing returns processes can also be described potheses based on temporal ordering--the possibility as self-reinforcing or positive feedback processes. that the particular sequencing of events or processes We face,then,a choice between a broader and a may be a key part of the explanation for divergent narrower conception of path dependence.Frequently, outcomes.Finally,grasping the implications of wide- authors are not explicit about which of these two spread path dependence can help orient political sci- meanings they intend.To establish greater clarity,this entists to a realistic,which is to say modest,set of essay employs the term in the narrower sense,that is, aspirations regarding the possibilities for achieving social processes that exhibit increasing returns.The parsimony and predictability in the study of politics. fuzziness that has marked the use of this concept in social science suggests that the greater range offered by PATH DEPENDENCE AND INCREASING the broader definition has come at a high price in RETURNS analytical clarity.Path dependence has been a victim of what Sartori(1970)called concept stretching.Different Analysts are increasingly inclined to invoke the concept of path dependence,but clear definitions are rare.In types of temporally linked sequences are generated in different ways and have different implications (Abbott practice,usage tends to fluctuate between a broader 1983,1990;Pierson n.d.b).These distinctive kinds of and narrower conception.In the broader version,path social processes,which have been bundled together, dependence refers to the causal relevance of preceding must be disentangled and systematically explored.Lim- stages in a temporal sequence.William Sewell (1996. iting the concept of path dependence to self-reinforc- 262-3),for instance,suggests path dependence means ing processes in no way precludes the investigation of "that what happened at an earlier point in time will other ways in which sequences can matter in explaining affect the possible outcomes of a sequence of events social outcomes.It does encourage clear argument occurring at a later point in time."This usage may about distinct claims.1 entail only the loose and not very helpful assertion that "history matters,"although it may also be presented with more rigor.To take an example offered by An- 1 Another strategy would be to use a broader conception of path dependence and then distinguish subtypes,exploring how these are drew Abbott (1983,131),the contemporary signifi- generated in different ways,with different consequences (Mahoney cance of a group's organization of 40%of its potential n.d.).Because path dependence is often invoked without further membership depends greatly on whether that member- clarification,however,this option seems more problematic.Ulti- ship used to be 100%or 10%.Note that Sewell's mately,such definitional disputes remain intractable.What is critical is that researchers be clear and consistent about what they mean definition involves no necessary suggestion that a par- when they employ the concept and recognize the importance of ticular path is difficult to exit.Rather,the claim is that differentiating among distinct processes. 252