Introduction: behavioural public policy and bounded interdisciplinarity
In his book How Far to Nudge? Assessing Behavioural Public Policy (2018), Peter John charts the startling rise of behaviourally informed public policies. Fusing the insights of psychological, behavioural and economic sciences, behavioural public policies (BPPs) are associated with the development of governmental interventions in areas of public health, environment and personal finance (inter alia), which are predicated on more empirically grounded and accurate understandings of human motivation and action (see Thaler & Sunstein, Reference Thaler and Sunstein2008; Oliver, Reference Oliver2017; Whitehead et al., Reference Whitehead, Jones, Pykett, Howell and Lilley2017; John, Reference John2018). In the opening chapter of How Far to Nudge, John argues that the science behind BPP is ‘genuinely interdisciplinary’ (Reference John2018, p. 4). We take the notion of genuine interdisciplinarity as our point of departure. John's statement is of interest to us because it simultaneously is unquestionably true, while also raising important questions about the particular form that interdisciplinarity takes in relation to BPP. In the analysis that follows, we critically analyse the nature of the dominant interdisciplinary dialogues that have informed BPPs and suggest that it is characterized by a distinctly bounded mode of interdisciplinarity. This paper considers the practical implications of the bounded interdisciplinary form of BPP and the more general theoretical implications of bounded understandings of interdisciplinarity for critical analyses of interdisciplinary endeavour.
We understand BPP as a distinct community of agents and aligned practices, embodying a coherent package of symbols, ideas, methods and political and ethical outlooks (Ball & Feitsma, Reference Ball and Feitsma2018). A crucial trait of this community is its use of techniques that are neither regulatory nor market/incentive based (although certain BPP insights can be used to reframe regulatory and market policies). Instead, BPP utilizes psychological insights (largely drawn from cognitive and behavioural psychology) into the nature of human decision-making in order to develop prompts to action that are potentially effective but easy to resist (see Thaler & Sunstein, Reference Thaler and Sunstein2008). To put things another way, BPP exemplifies the application of psychological governance within free societies (Whitehead et al., Reference Whitehead, Jones, Pykett, Howell and Lilley2017). Within this paper, we are broadly supportive of BPP's attempts to devise programmes that challenge the dehumanized assumptions of market rationality that have informed neoliberal government for the last 35 years (Davies, Reference Davies2014). Notwithstanding this, our primary goal is to contribute towards and extend critical theoretical perspectives on this movement (Furedi, Reference Furedi2011; Davies, Reference Davies2014; Leggett, Reference Leggett2014; Lepenies & Malecka, Reference Lepenies, Malecka, Drerup and Dessauer2016; Mulderrig Reference Mulderrig2017; Pedwell, Reference Pedwell2017; Feitsma, Reference Feitsma2018a, Reference Feitsma2018b).Footnote 1 We ultimately claim that the interdisciplinary zone associated with BPP is characterized by a pronounced lack of engagement with a broad range of social sciences, which share similar concerns, but employ very different analytical and methodological perspectives (e.g., Shove Reference Shove2010; Jones et al., Reference Jones, Pykett and Whitehead2013; Mols et al., Reference Mols, Haslam, Jetten and Steffens2015; Lepenies & Malecka, Reference Lepenies, Małecka, Lever and Poama2018; Pykett, Reference Pykett2018). There are many ways of demonstrating the critical contribution that the broader social sciences could make to behavioural policy-making. In this paper, we focus on the specific contributions that are evident within our own disciplines of critical human geography and public administration. In the analysis that follows, we focus on two concepts: the geographical notion of context and the public administration question of evidence. As we see, questions of context and evidence are central concerns – indeed, leitmotifs – of BPP. In our analysis, we aim to show how the bounded interdisciplinarity of this community can result in partial understandings of context and evidence, which arguably decreases its ability to solve complex public issues. At the same time, we also aim to show how this critique does not universally apply, as in some parts of the field encouraging unbounding of BPP's interdisciplinarity can be observed.
The arguments presented in this paper are grounded in long-term qualitative fieldwork stemming from two independent research projects on BPP. For one of the projects, over 100 qualitative interviews have been carried out with BPP markers, experts and practitioners in six countries around the world over a nine-year period. The other project is grounded in four years of fieldwork on BPP experts in Dutch central and local government, which involved carrying out 36 interviews and conducting over 475 hours of participant observation in the field. To empirically substantiate our analysis of BPP, various case studies have been drawn from these research projects. In selecting these case studies, we followed a logic of theoretical/purposive sampling, purposefully screening for cases that helped us in showing the nature of the field's interdisciplinarity, and particularly the varieties that exist therein (Etikan et al., Reference Etikan, Musa and Alkassim2016). We thus also purposefully screened for counterexamples that ran against the initial main claim of bounded interdisciplinarity. We present these counterexamples to show where and how the field is to some extent already making critical interdisciplinary excursions. Due to this purposive sampling strategy, these cases should not necessarily be taken as representative for the field in a wider sense.
BPP in a critical interdisciplinary context
The interdisciplinary origins of BPP
In his personal history of BPP, Misbehaving: The Making of Behavioural Economics, Richard Thaler (Reference Thaler2015) provides valuable insights into the interdisciplinary origins of the movement. Thaler describes how in the 1970s he began compiling a list of peculiar human behaviours: the kinds that were inconsistent with economic theory. In trying to make scientific sense of these behaviours (the kinds that see us favouring the present over the future, status quo over change and the behaviours of others over our own judgement), Thaler describes a chance encounter that led him to become aware of the pioneering work of Daniel Kahneman and Amos Tversky. For several years, Kahneman and Tversky had been attempting to bring psychological explanations into economic theory (see Kahneman et al., Reference Kahneman, Slavic and Tversky1982; Kahneman, Reference Kahneman2011). Their research suggested that humans lack the time and cognitive bandwidth necessary to consistently behave in rational ways (Camerer, Reference Camerer, Loewenstein and Rabin2003). This body of scholarship also showed that if economists wanted an account of actually existing human behaviour, it appeared they needed an interdisciplinary dialogue with certain branches of the psychological sciences. The empirical work of Kahneman, Tversky, Thaler and others generated a fusion between cognitive psychology and economics that would eventually become the interdisciplinary field of behavioural economics. Behavioural economists now provide the scientific bedrock for BPP and dedicate their time to better understanding the bounding of human rationality.
It is important to recognize that behavioural economics was not the first, or only, form of interdisciplinary engagement between the psychological and economic sciences. Sent (Reference Sent2004, p. 738) has identified early, pre-Freudian interdisciplinary dialogues between economics and psychology in the mid-nineteenth century (these interactions were based on the economic application of psychological notions of sensation, stimulus and response). Oliver's (Reference Oliver2017) recent review of BPP also traces the origins of this dialogue to the very birth of the discipline of economics. Economists’ rejection of Freudian accounts of unconscious behavioural motivations and Milton Friedman's powerful defence of the rationality principle did, however, stifle interdisciplinary dialogue during large parts of the twentieth century (Oliver, Reference Oliver2017). The renewed interdisciplinary engagement between psychology and economics in the post-war period is linked to two things: (1) the cognitive revolution in the psychological sciences; and (2) the pioneering work of Herbert Simon on bounded rationality (Simon, Reference Simon1957; Sent, Reference Sent2004, p. 739; see also Strauss, Reference Strauss2009). According to Sent (Reference Sent2004), the cognitive revolution in psychology and the work of Herbert Simon facilitated the emergence of an old school of behavioural economics, which drew together a series of scholars working at the interface of psychology and economics. Sent argues that this old school was characterized by a ‘dismissal of the mainstream [economic] focus on profit and utility maximisation and equilibrium as well as an effort to develop an alternative’ (Sent, Reference Sent2004, p. 741). At the heart of the old behavioural economics school project was a desire to replace the figure of Homo economicus with a new, empirically grounded theory of human subjectivity.
The most significant and sustained form of twentieth-century interdisciplinary dialogue between psychology and economics was, however, facilitated by a different group of behavioural economists. According to Sent (Reference Sent2004, p. 742), the new behavioural economics school emerged out of the 1970s work of the aforementioned Daniel Kahneman, Amos Tversky, Baruch Fischoff and Paul Slovic. This new school deviated from the older cohort of behavioural economists to the extent that ‘they started from the rationality assumption that has characterised mainstream economics and next analysed departures from this yardstick, as opposed to developing an alternative one’ (Sent, Reference Sent2004, p. 743). It is difficult to discern precisely why new behavioural economists should have sided, broadly, with the rationality assumption. As Sent astutely observes, ‘While new behavioural economics seeks to strengthen mainstream economics, there is nothing inherent in appeals to psychological insights that requires this’ (Reference Sent2004, p. 750). It could reflect a normative commitment to the notion that rational action is right, and thus, even if it does not reflect actually existing behaviour, it must still be assumed as a goal. Alternatively, it may speak to a more theoretical presumption that rationality can still explain much in economic life, even if not everything. What is clear is that in taking rationality as the criterion against which psychological studies of the irrational should be measured, certain branches of new behavioural economics sought to increase the explanatory power of economics and suggest that new forms of explanatory power for human conduct need not be forged too far outside of the discipline (Sent, Reference Sent2004). We do acknowledge here, however, the heterodox nature of new behavioural economics. This heterodox nature means that at times it has offered more radical challenges to the explanatory logics of neoclassical economics. Sugden's (Reference Sugden2018) recent work has, for example, suggested that economics should abandon its rationality assumption concerning the normalcy of individual self-interest and see cooperative preferences less as psychological errors and more as an expected part of market economies.
The complementary alignment of certain branches of psychology and economics within the new behavioural economics school was significant to the form that subsequent interdisciplinary inquiry within BPP would take. The work of the old school of behavioural economics suggested that novel theories of human judgement that sat clearly outside of existing economic thinking were required, thus inviting potentially more open forms of interdisciplinary inquiry. The new behavioural economists developed a more instrumental form of interdisciplinarity within which psychology was used to explain and correct the specific instances where economic theories of rational human action proved to be consistently erroneous. Significantly, in the context of this paper, this form of heavily circumscribed interdisciplinarity was based upon an increasingly experimental form of economics, which sought to use verifiable psychological methods to iteratively refine economic modes of explanation. To these ends, it is clear that the interdisciplinary form of behavioural economics (and, by extension, BPP) was about the alignment of economics with very specific branches of psychology (particularly the cognitive and behavioural traditions). From its very initiation, the scientific basis for BPP was effectively excluded from significant chunks of the very discipline it was pairing with. While interdisciplinarity rarely involves the functional integration of entire disciplines, it is clear that BPP is based on scientific dialogue that has externalized certain psychological insights into the nature of human emotionality and irrationality. This externalization processes has involved the exclusion of psychoanalytical insights into the human condition, and, more recently, has made it difficult for BPP to incorporate the recognition that is being given to the social psychology of emotions (Keltner et al., Reference Keltner, Oatley and Jenkins2014). As we will discuss in greater detail in the second half of this paper, this circumscribed (or bounded) interdisciplinary dialogue had critical impacts on the relationship between BPP and questions of context and evidence.
Critical interdisciplinary perspectives on BPP
In order to develop a critical perspective on the interdisciplinary form of BPP, it is necessary to consider the very nature of what it is to be interdisciplinary. In general terms, interdisciplinary activity is defined as research that involves the ‘integration of knowledge originating in two or more [academic] fields,’ and that is distinct from cross- or multi-disciplinary work, which involves ‘contributions from two or more fields to a research problem’ (Jacobs & Frickel, Reference Jacobs and Frickel2009, p. 45). The distinction between knowledge integration and knowledge contributions suggests a demarcation between two forms of academic collaboration. While integration suggests the a priori synthesis of research insights and techniques in order to openly explore a knowledge problem in new ways, knowledge contributions are typical of breaking down a research problem into discrete parts that can be explored by different disciplines while avoiding any sustained engagement between those disciplines (MacLeod & Nagatsu, Reference MacLeod and Nagatsu2018). According to MacLeod and Nagatsu (Reference MacLeod and Nagatsu2018, pp. 2–3), interdisciplinarity is also characterized by three additional features: a focus on real-world problems; the development of more comprehensive perspectives on problems; and a fundamentally disruptive element. The focus on real-world problems is a feature of interdisciplinary endeavours because by definition these are problems that do not arise within the confines of existing disciplinary purviews. The comprehensive nature of interdisciplinarity is associated with a ‘more holistic or systematic understanding of a set of phenomena’ (MacLeod & Nagatsu, Reference MacLeod and Nagatsu2018, p. 3) and related attempts to position a problem within a more complex web of interpretation. Interdisciplinary inquiry's disruptive nature is a feature of modes of analysis that lead to the destabilization of existing disciplinary modes of analysis and the formation of novel lines of academic investigation (MacLeod & Nagatsu, Reference MacLeod and Nagatsu2018).
We acknowledge that the BPP movement can be considered interdisciplinary, particularly in relation to its focus on real-world problems that exceed established disciplinary concerns (namely the irrational behaviours of economic actors) (see Sanders et al., Reference Sanders, Snijders and Hallsworth2018). Crucially, however, we think that on the criteria of comprehensiveness and disruptiveness, the degree of interdisciplinarity is considerably limited. In its tight embrace of certain disciplines and subsets thereof – reflecting the particular interdisciplinary engagement between cognitive psychology, behavioural psychology and economics – BPP overlooks a whole set of other disciplinary fields, including cognitive anthropology, cultural studies and other branches of psychology, as well as our own fields of critical human geography and critical public administration. However, the recent emergence of the field of ‘behavioural public administration’ (Grimmelikhuijsen et al., Reference Grimmelikhuijsen, Jilke, Olsen and Tummers2017), merging insights from behavioural science and public administration, demonstrates that the field of public administration is certainly not entirely excluded from BPP's knowledge content. Rather, it is the more critical strands of public administration, which scrutinize and problematize trends such as rationalization, scientization and psychologization, which appear to be eclipsed. Table 1 outlines the interdisciplinary forms of engagements that characterize BPP and the complementary, but largely unintegrated disciplines from which additional perspectives could be gleaned. It shows how BPP is interdisciplinary in certain ways, but simultaneously points to the scientific territory in which it appears to lack substantive interdisciplinary engagement (see also Lepenies & Malecka, Reference Lepenies, Małecka, Lever and Poama2018; Pykett, Reference Pykett2018; Jones et al., Reference Jones, Pykett and Whitehead2013). Notwithstanding BPP's valuable contributions to refining cognitive and behavioural accounts of human decision-making, its interdisciplinarity thus seems to be of a relatively comfortable kind.
It is difficult to systematically prove our claim that BPP is characterized by a form of bounded rationality (particularly given the growth of related research in this area over the last decade). We do argue, however, that there are several reasons to think that this claim may be valid. First, it is important to establish that while the theories of behavioural economics, upon which BPP is based, have become increasingly heterodox, we claim more specifically that it is BPP itself that has tended towards more limited interdisciplinary engagements. Writing in this journal, for example, Hansen (Reference Hansen2018, p. 192) has observed that in attempting to translate the ideas of behavioural sciences into policy solutions, BPP has often been guilty of ‘labelling behavioural phenomena with behavioural terminology from the desktop’ of behavioural economics. According to Hansen, this tendency has impeded more sustained, diagnostic research into the nature of real-world problems. This is precisely the form of applied field research that would open up the study of behavioural problems to a broader spectrum of disciplinary perspectives and enable the development of new conceptual vocabularies. It is important to note, of course, that the particular interdisciplinary bounding of BPP around well-established core principles of behavioural economics has as much to do with the political pressures for quick wins as any particular interdisciplinary bias. Beyond this specific claim, however, it is also clear that the interdisciplinary space defined by behavioural economics and the broader field of economic psychology is characterized by relatively constrained levels of interdisciplinary engagement. In a survey of published work in the Journal of Economic Psychology, for example, it was recognized that while undoubtedly interdisciplinary in scope, contributory authors were overwhelmingly from the behavioural and economic sciences, with additional inputs from the fields of consumer and market research (Kirchler & Hölzl, Reference Kirchler and Hölzl2006).
BPP and understandings of evidence
BPP, public administration and the quirks of ‘what works’
Having established a broad overview of the interdisciplinary integration and non-integration between scientific disciplines within BPP, this paper now zooms in on a particular non-integrated interdisciplinary territory. Specifically, it brings into view insights from (critical) public administration. A classic theme within this field is the use of knowledge, asking the question of how knowledge comes to shape policy decisions through being produced, defined, selected and authorized in certain ways (Lindblom, Reference Lindblom1959; Weiss, Reference Weiss1979; Nutley et al., Reference Nutley, Morton, Jung and Boaz2010). More recently, this theme has been addressed in a particular concern with ‘evidence-based policy’ (EBP) (Newman, Reference Newman2016), entailing an agenda predicated on a desire to gather epistemic knowledge that provides rigorous, codifiable insights into ‘what works’ (Parsons, Reference Parsons2002). Although BPP has emerged two decades later than EBP, both agendas are interwoven, and it could be reasoned that they have been developing ‘in symbiosis’ (Einfeld, Reference Einfeld2018). In accordance with EBP, BPP views the relationship between science and policy from a rationalist perspective (Parsons, Reference Parsons2002; Lodge & Wegrich, Reference Lodge and Wegrich2016; Feitsma, Reference Feitsma2018a, Reference Feitsma2018b, Reference Feitsma2019). This rationalism entails particular assumptions about how policies can be developed and how the policy process can be organized. Policy-making is viewed as a matter of technical problem-solving through rational analysis. While the field of BPP appears to prefer to improve policy incrementally – in this sense deviating from a grand rationalist theory of design – it still seeks to reach those incremental improvements in a highly rationalized way, with comprehensive analyses and rigorous experimental methodologies. BPP's rationalist ambitions, aspiring to infuse policy-making with the most rigorous scientific analyses and methods, are perhaps most visible in its advocacy of randomized controlled trials (RCTs) and the rational policy cycle (Ball & Feitsma, Reference Ball and Feitsma2018), straightforwardly moving from problem definition to implementation.
Such a rationalist perspective on policy-making has been widely contested in the critical EBP literature. To begin with, the idea that it is possible to start from a shared, sharply defined problem perception is already problematic (Lindblom, Reference Lindblom1959). This especially applies to ‘wicked problems’, which are characterized by high levels of both empirical and normative uncertainty, meaning that even their status as ‘problems’ is disputed. In such cases, there is no clear-cut behaviour change goal to begin with, and top-down attempts to formulate such an ambition risk evoking resistance and further amplifying uncertainty. Also problematic are the assumptions regarding analytical comprehensiveness in policy design that seem to be implicit within EBP and BPP – at least as judged by its frontstage communications (Feitsma, Reference Feitsma2018a). Such assumptions neglect that policy decisions are made in a political-administrative context of uncertainty, limited resources and bounded rationality (Lindblom, Reference Lindblom1959). In practice, policy analyses remain inconclusive, selective and multisided and do not per se follow a linear, step-by-step process. Technically complex and labour-intensive evaluation methods like RCTs are only feasible to a limited extent. And even when used, such rigorous methods do not produce certain and transferable knowledge, but rather provide provisional and isolated knowledge about ‘what worked’ (Biesta, Reference Biesta2007, emphasis added) in a specific context (Deaton & Cartwright, Reference Deaton and Cartwright2018). Evidence about the specific impacts of policy solutions often remains of an inconclusive nature (Esterling, Reference Esterling2004).
Another issue is that BPP appears to make remarkably little public mention of the political nature of science–policy interaction. Generally, it seems to present a selective view on the politics within academia, which is the site of many conflicts, controversies and ‘science wars’ between diverging paradigms (although see John, Reference John2018). Likewise, it displays limited perception of the politics within the policy arena (although see Halpern, Reference Halpern2015), which is affected by ideological struggles and bureaucratic ‘turf wars’. Moreover, the field calls little attention to the political dynamics occurring in the space between science and policy. Critical public administration scholars studying evidence use have repeatedly pointed out that policy ‘facts’ do not speak for themselves, but become authorized as ‘evidence’ through filtration processes (e.g., Cairney, Reference Cairney2016; Strassheim, Reference Strassheim2017). Policy-makers – both consciously and unconsciously – fabricate, ignore, cherry-pick or dispute evidence, or filter it in other ways (Lindblom, Reference Lindblom1959; Weiss, Reference Weiss1979; Ingold & Monaghan, Reference Ingold and Monaghan2016). EBP (and also BPP) is thus best thought of as a normative ideal, or a ‘useful myth’ (Boswell, 2018) that provides politico-epistemological legitimacy through the authority of positivist science.
The ‘politics of expertise’ (Fischer et al., Reference Fischer, Torgerson, Durnova, Orsini, Fischer, Torgerson, Durnova and Orsini2015) that takes place at the science–policy interface reflects the struggle between scientific disciplines competing over power and legitimacy. BPP's tendency towards fairly naïve objective/rationalist understandings of evidence tends to neglect this. Moreover, we claim that the bounded interdisciplinarity of BPP – entailing a convenient fusing of economics with certain branches of psychology – is, in part, a product of the forms of scientific power struggle that BPP's approach to evidence denies. In this power struggle, BPP is continuously reproducing its own disciplinary assumptions while disempowering others (particularly the structuralist social sciences run; Jones et al., Reference Jones, Pykett and Whitehead2013). This may lead to an over-psychologized policy process in which policy design is narrowly approached from an individualist, cognitive-economic orientation that does not thoroughly explore contexts at the structural level (Shove, Reference Shove2010; also see the following section's discussion of context). This risk of over-psychologization may also be reflected in a strong prioritization of RCT knowledge and the resulting disregard of a whole series of other forms of knowledges (Deaton & Cartwright, Reference Deaton and Cartwright2018; Jones & Whitehead, Reference Jones and Whitehead2018). In particular, these process tend to see qualitative, local, tacit and phronetic (Parsons, Reference Parsons2002) types of knowledge being excluded.
Reimagining the use of evidence within BPP
Although we would contend that a large part of BPP is susceptible to these EBP critiques, simultaneously it must be noted that we have observed BPP practices that (to some extent) have been provisionally responding to these critiques. Such practices are opening up an interdisciplinary dialogue between BPP and critical public administration. To further inspire such dialogue, this section gives two illustrations of such practices, offering alternative and interdisciplinary unbounding (yet also in some other ways still interdisciplinarily bounded) ways of gathering and valuing evidence.
Pluralist forms of BPP in Dutch environmental policy-making
For a first example of alternative BPP practices, we take a closer look at some behavioural policy initiatives in the area of Dutch environmental policy. One actor of interest is the Behavioural Insights Team for Infrastructure and Water Management (BIT IenW), which is noteworthy due to the implicit theoretical outlook that shapes its projects. This outlook stepped outside the confinements of behavioural science and also invited insights from public administration and sociology. This was reflected in BIT IenW's analytical practice, which not only included a conventional micro-level psychologist's perspective, but also a macro-level sociologist's perspective (see also Feitsma, Reference Feitsma2018b). Another part of BIT IenW's move beyond strict behavioural science was how it defined its problem cases and consequently how it went about gathering valuable evidence. For instance, one project focused on overcoming some of the negative consequences of the distribution of goods within urban areas, particularly directed at diminishing noise and air pollution traffic congestion and unsafe traffic situations (Kennisinstituut voor Mobiliteitsbeleid, 2017). A particular behavioural challenge revolved around getting Internet consumers to pick up products at a designated location (instead of having it sent to their home addresses), as that would result in reduced traffic congestion. For this case, BIT IenW assigned an economically trained scientist specialized in urban technology to conduct a behavioural analysis (Kennisinstituut voor Mobiliteitsbeleid, 2017). Interestingly, the analysis reflected influences from a range of alternative disciplines, varying from sociology to urban studies and public administration. Notably, the policy problem was defined as a ‘wicked problem’ that reflected a classic dilemma of a ‘tragedy of the commons’ (Kennisinstituut voor Mobiliteitsbeleid, 2017). Aware of the ‘wicked’ nature of this issue, partly stemming from its actor-related complexity, BIT IenW refrained from identifying individualized behaviour change strategies. Instead, it focused on finding higher-level solution strategies particularly related to which actors played a key role in optimizing urban distribution and how collaboration could be facilitated. The report was underpinned by several broad theories about ‘wicked problems’, policy networks and public–private partnerships. These theories did not so much offer specific, instrumental insights about ‘what works’ than rather broader, more holistic insights about the complex nature of public policy issues and how to best address that complexity. In taking these higher-level theoretical perspectives as the guiding evidence, this team moved beyond the common practice of evidence-gathering within BPP, which is to search for highly specific, micro-theoretical ‘bits’ of evidence about the impacts of single interventions.
Besides theoretical pluralism, one can also observe methodological diversity in some of the Dutch BPP practices focusing on environmental policy. A particular example of this was offered by a behavioural expert working at the Dutch executive agency Rijkswaterstaat. When prompted about his methodological practice, he acknowledged the explanatory value of RCTs while at the same time downplaying RCTs as being just one instrument in the behaviour expert's evaluative toolkit. Moreover, he stressed the importance of alternative methodologies. Particularly, he combined creative thinking techniques, such as ‘knowledge-based brainstorms’, with the strategy of harnessing local knowledge within communities in order to develop innovative and workable solutions:
How you make that translation [from analysis to local solutions]? That's quite a tricky one. I once organized a benchmark session, just showing a movie of Cialdini and his principles [of social influence] and then letting the audience think about how they could apply this in [the policy area of] waste separation. You'll notice that they get through the movie quite easily and that applying each behavioural change technique to the specific situation and the identified ‘customer journeys’ yields some nice results. So that's one nice way to do it. Those people also know the target group so they're well able to think along. [It is important to] engage them with these techniques and let them think along about how to modify those or assess whether they work or not. That they develop a sensitivity for it. I don't think you can do all of that by yourself.
The practices of BIT IenW and the expert at Rijkswaterstaat reflect a degree of pluralism regarding the use of theories and methodologies. In how evidence was gathered and valued in these cases, one can see a move beyond the typical BPP tendency to only search for micro-theoretical behavioural evidence about ‘what works’.
Behavioural Insights Team UK's ‘Behavioural Government’ report: a convincing pre-mortem of BPP?
For a second example, we consider a report, titled ‘Behavioural Government’ (Hallsworth et al., Reference Hallsworth, Egan, Rutter and McCrae2018), which has recently been published by the Behavioural Insights Team UK. Interestingly, this report breaches with frontstage conventions by explicitly engaging in debate with the critical EBP literature. More specifically, the report takes seriously the critique that has been aptly formulated as the ‘rationality paradox’ (Lodge & Wegrich, Reference Lodge and Wegrich2016), holding that while the field is all too aware of the bounded rationality of the citizen, it shows peculiarly little recognition of the bounded rationality of the public official. ‘Behavioural Government’ therefore does begin to look into government's own bounded rationality. To do so, it reviews the various sorts of biases that have been found to mark the policy process. It arrives at a whole list of biases that are structured along the policy stages of noticing, deliberating and executing. The review draws on a wide range of academic (mostly experimental) studies in the area of ‘behavioural public administration’. After identifying these biases, the report reflects on ways to overcome them. For instance, to overcome the confirmation bias of officials to tend only to take in evidence that supports the views that they already hold, one advised counterstrategy is to ‘[b]uild in opportunities to change course and revisit assumptions’ (Hallsworth et al., Reference Hallsworth, Egan, Rutter and McCrae2018, p. 12).
‘Behavioural Government’ is innovative in how it shifts the field's common locus of analysis. Instead of analysing the citizens and businesses that are subjected to government policies, the government itself becomes the locus of analysis. Through this shift in focus, this variant of BPP shows itself to be more reflective about the ways in which decisions made by government officials are shaped by their personal background, wider socio-material context and varied unconscious choice processes. In exploring these issues, the report engages in a broader interdisciplinary dialogue. This dialogue is also embedded institutionally, as ‘Behavioural Government’ has been written in direct collaboration with critical evidence-based scholars, including Paul Cairney, Martin Lodge and Kai Wegrich. ‘Behavioural Government’ might even be furthering the critical EBP agenda in ways that this programme itself has thus far not been able to. That is because the report has managed to translate a diffused set of academic theories about bounded rationality within government into a more unified, intelligible and policy-relevant model, persuasively stacked with a rich body of experimental evidence. The report is, in this sense, ‘brokering’ EBP critiques, moving them into the policy sphere and translating them into the policy lexicon.
Nonetheless, there are some other aspects in which ‘Behavioural Government’ seems more limited in terms of its critical interdisciplinary engagement regarding evidence use. A first limiting point is that the report shows little acknowledgement of the political drivers that impact how evidence is taken up in the policy process. The report makes an explicit distinction between ‘programmatic’ and ‘political’ policy evaluation. Programmatic evaluation means ‘looking at observable costs and benefits to society and comparing the policymaker's original intention with the eventual outcome,’ while political evaluation is about ‘the way policies are being perceived and debated among their stakeholders’ (Hallsworth et al., Reference Hallsworth, Egan, Rutter and McCrae2018, p. 16). The report then informs the reader that it has chosen to adopt the programmatic perspective. From a critical point of view, however, this programmatic/political distinction is in and of itself problematic. It underestimates how deeply intertwined politics and policymaking are (Strassheim, Reference Strassheim2017). Seemingly neutral programmatic evaluation of ‘observable costs and benefits to society’ inevitably has to be selective in practice in terms of what costs and benefits it researches, for whom and how it does so. Forced to be selective, all sorts of choices must be made, all situated within a political context of value conflicts between actors, interests and ideas. Behind constructs like ‘observable’ and ‘society’ lie political questions about who gets to decide what these constructs mean and what they include and exclude. As even such basic elements are already value laden and evoke power struggles, programmatic evaluation cannot escape the territory of ‘the political’.Footnote 2
Moreover, the critical interdisciplinary dialogue could have been deepened if ‘Behavioural Government’ had moved beyond conventional theoretical and methodological outlooks. In terms of methods, the report heavily relies on experimental studies, implicitly conveying that non-experimental types of studies yield no valuable evidence on this. The opposite is actually true, as, for instance, cross-sectional surveys (admittedly, the report includes one small survey) and in-depth qualitative studies (e.g., Nutley et al., Reference Nutley, Morton, Jung and Boaz2010; McGoey, Reference McGoey2012; Boswell, 2017) can offer insights into governmental evidence use in ways that experiments cannot. In terms of theories, ‘Behavioural Government’ also remains somewhat tied to its interdisciplinary comfort zone, as it is researching governmental biases by and large from a psychological-economic, individualist perspective, zooming in on the micro-level choice processes of individual agents rather than exploring limits to rationality in the context of wider governmental structures and broader societal developments at the macro-level (see Sanders et al., Reference Sanders, Snijders and Hallsworth2018, for an acknowledgement of the social limitations of BPP). Admittedly, ‘Behavioural Government’ (Hallsworth et al., Reference Hallsworth, Egan, Rutter and McCrae2018, p. 13) does acknowledge the role of wider structures at several points, stating that ‘[r]eforms cannot focus on individuals in isolation – they also need to consider how systems, processes and institutions create behaviours.’ However, this line of thought has not informed the report in a deep sense.
To conclude this case study, and to stick with the report's own terminology, ‘Behavioural Government’ could be seen as a key attempt in conducting a ‘pre-mortem’ of BPP, coming from a major frontrunner in the field. The report has explored how critiques of BPP's rationalist assumptions might imply a collective failure of the field and how such failure could be avoided. This deliberative turn within BPP has to be applauded, and it is something that can be expected to endure, particularly given the increasing focus on bounded rationalities within government as studied by scholars of ‘behavioural public administration’ (Grimmelikhuijsen et al., Reference Grimmelikhuijsen, Jilke, Olsen and Tummers2017). Nevertheless, we have also pointed out aspects in which the ‘Behavioural Government’ report's interdisciplinary inquiry remains unconfrontational.
BPP and understandings of context
BPP, geography and the issue of context
Our second set of reflections on the bounded interdisciplinarity of BPP concerns the issue of context. Context is a particularly important concept within BPP. First, the decision-making context is a crucial lens through which a BPP perspective seeks to observe and understand bounded rationality. While bounded rationality is, in part, seen as a product of the internal limitations in the cognitive bandwidths of individuals, behavioural contexts (whether it be canteens, streets or supermarkets) are also seen to limit optimal decision-making. This emphasis on the role of context represents a crucial departure from neoclassical economics (and, indeed, liberal political theory), where economic decision-making appears to operate in a context-less non-space of desert island-like solitude. Second, context is important within BPP to the extent that it offers a key vector in and through which behavioural polies are themselves pursued (see Jones et al., Reference Jones, Pykett and Whitehead2013; Carter, Reference Carter2015; Whitehead et al., Reference Whitehead, Jones, Howell, Pykett and Lilley2018). BPP is consequently predicated upon how shifts in social, material and increasingly digital contexts (including places, buildings and data platforms) of decision-making can offer the basis for effective shifts in recalcitrant habits and behaviours. It commonly targets choice architectures and environments as a basis for behavioural government.Footnote 3 Third, context is also evident analytically within BPP in relation to concerns over replication (or the extent to which a change of context may alter the observed effects of an intervention) and heterogeneous treatment effects (where subjects may be effected differently by a given intervention).
The purpose of this section is to consider the potential practical and intellectual implications of extending the interdisciplinary horizons of BPP in relation to issues of context beyond the behavioural and psychological. To these ends, we focus specifically on existing work within the geographical sciences. Work within human geography has a long association with questions of context. Indeed, the very nature of the geographical discipline emphasizes the importance of developing spatial and temporal perspectives on various social, economic and political issues. Given the significance of context within BPP, it is notable that the geographical sciences sit outside the interdisciplinary interactions associated with BPP (Whitehead et al., Reference Whitehead, Jones, Howell, Pykett and Lilley2018). However, it is important to note that geographical critiques of the contextual assumptions of BPP have already emerged. At a general level, Strauss (Reference Strauss2008, p. 143) argues that within behavioural economics the notion of context ‘is underdetermined and remains largely untheorized.’ In his analysis of public health initiatives that deploy BPP, Carter (Reference Carter2015) has argued that while related policies focus on important local social and infrastructural contexts, they tend to ignore broader contextual processes related to class and race. Hence, it is in relation to the at best simplified and at worst underdetermined application of contextuality within BPP that we claim geography could productively contribute to this interdisciplinary field. According to Strauss (Reference Strauss2009, pp. 308–309):
A geographical conception of context as the decision-making environment encapsulates the permeable and mutable scales implicated in the decision-making ‘moment’. Thus, the articulation of space and place as part of the conceptual working through of the notion of context must include the scalar range of individual experience: from the individual to the global, from the intimate to the distanced, from embodied to disembodied forms of experience.
From a geographical perspective, the contextualization of phenomena (whether it be human habits or neighbourhood redevelopment) is about more than merely situating them within local processes. Within geography, context is routinely understood as the particular coming together of local and supra-local forces to shape human behaviour and social processes in space (see Whitehead et al., Reference Whitehead, Jones, Howell, Pykett and Lilley2018). This approach to context does not mean that an appreciation of the role of psychological processes and design environments offered within BPP is not important. Rather, it suggests that the contextual drivers of human decision-making cannot be determined, or hoped to be changed in the long term, through a focus on local design environments alone. Critically, within geography, a contextual perspective is used to understand the spatial differentiation of things like human behaviour. Within BPP, the contextual project is currently more about understanding the generic impact that context has on human behaviour across spaces.
Rethinking BPP's contextual project
We now consider the implications of a geographical perspective on questions of context to the study of behavioural phenomena. In doing so, we also consider existing attempts within BPP to broaden its contextual horizons and how these are nonetheless limited by the bounded interdisciplinarity of the project.
Acknowledging the non-immediate context in organ donor registration policies
The contextual limitations of BPP are already evident in one of its most celebrated policy initiatives. Opt-out organ donation registers have become something of an emblem for behavioural policymaking (see Thaler & Sunstein, Reference Thaler and Sunstein2008). They are predicated on the notion that while the majority of people express a preference for donating tissue and organs after their death, many never actually get around to opting in to organ donor registers. BPP's solution to this problem has been to deploy one of its most powerful techniques – the resetting of defaults. By presuming consent for organ donation while making it easy for people to opt out of being on donation registers, millions of people were added to organ donor registers in nations including Belgium, Spain and Wales. But despite the putative success of opt-out organ donor registers, recent evidence suggests that they may not, at least in all cases, actually increase the number of organ transplants.
In December 2015, Wales moved to an opt-out organ donor system. Recent figures reveal that despite placing tens of thousands of extra people on the organ donor register, the policy change has made negligible difference to actual transplant levels (indeed, between 2015/2016 and 2016/2017, transplant numbers dropped by 27) (BBC News, 2017). It is our contention that the limitations of this policy initiative directly reflect the contextual shortcomings of BPP. The contextual failings of opt-out organ donation revolve around the fact that it tends to reduce donation to an individual action (or inaction) associated with being put on an organ donation register. While opt-out systems thus recognize the immediate contextual factors that shape organ donation decisions (particularly inertia and fear), they fail to account for the ways in which the ‘decision-making environment encapsulates the permeable and mutable scales implicated in the decision-making “moment”’ (Strauss, Reference Strauss2009, p. 308). To put things another way, opt-out organ donation registers generally fail to account for the connections between joining organ donor registers and the contextual factors that lead to organ transplants. The first contextual factor to consider here is the tendency of families, in the aftermath of the loss of a loved one, to override their (presumed) decision to donate their organs. Recent research has revealed that opt-out systems will lead to more families deciding to go against the donation wishes of their kin precisely because in such systems consent becomes less clear (Lin et al., Reference Lin, Osman, Harris and Read2018). In Spain, where more emphasis has been placed on understanding organ donation in the context of grieving families, the opt-out system has been much more successful. The second contextual factor relates to having greater support for logistically capturing, storing and transporting organs. Without appropriate funding to support expanded organ donation systems, it is unlikely that opt-out systems will be able to deliver significant changes in transplant rates.
Notwithstanding these issues, it is evident that BPPs in the area of organ donation are adapting to address their contextual limitations. There is a tendency to now use mandated choice as opposed to opt-out systems to promote registration on organ donation systems (whereby people are required to opt in or out of registers when they renew their driving license, for example). Such initiatives are, however, still characterized by a focus on decision-making moments, which fails to account for the varied, interconnected socioeconomic and emotional contexts within which human behaviour is situated. It is our contention that the narrow deployment of context within BPP is a product of the tendency of both cognitive psychology and neoclassical economics to focus on the individual as their primary unit of analysis. The constricted understandings of context can thus be interpreted to be a direct consequence of the bounded interdisciplinarity of BPP.
BPP, context and the Flint water contamination problem
An additional, salutatory example of contextuality within BPP relates to the pioneering work of the US Government's Social and Behavioural Sciences Team (SBST). The SBST was created during the Obama administration in order to support the development of BPP across relevant public policy areas in the USA. Significantly, the SBST worked to broaden the contextual remit of behavioural policies. The clearest evidence of the SBST's attempt to bring novel contextual perspectives into BPP can be seen in its work in Flint, Michigan. Following a change in water source supplying the town of Flint in 2014, the city's water started to suffer from contamination. The water contamination was the product of various carcinogens and bacteria being present in the new water supply and the lead that was entering the water following its interaction with old and poorly maintained pipes (see Stillman, Reference Stillman2017). The problems of water supply in Flint led President Obama to declare a state of emergency in the city in 2016. Further public health problems emerged as knowledge about the contamination of tap water spread. As people became wary of using tap water to wash their hands, there were outbreaks of shigellosis (a highly contagious bacterial infection) (see Nimishakavi, Reference Nimishakavi2016). The primary behavioural problems related to the Flint water crisis pertained to getting local communities to continue to use bottled water, to fit and regularly replace water filters within their homes and to maintain good handwashing habits (Nimishakavi, Reference Nimishakavi2016). These behavioural goals were, however, undermined by a prevailing sense of social injustice surrounding the crisis (with certain communities having had their lead pipes replaced more quickly than others) and a general sense of mistrust towards government guidance concerning appropriate forms of water behaviour (government advice had initially suggested that Flint's water was safe to drink) (Stillman, Reference Stillman2017).
In relation to the social justice and governmental mistrust issues surrounding the Flint water crisis, the SBST advocated a new approach to behavioural context. This new approach immediately sought to move beyond a concern with the individual psychological and economic drivers of human decision-making, to understand the role that community norms and cognition play in shaping individual decision-making. The SBST sought to work with various community groups to better understand why residents might be unwilling to accept and act upon advice they received from governmental officials regarding water filter maintenance and the safety of using tap water for handwashing. What is interesting in relation to the work of the SBST in Flint is that, in trying to understand the contextual challenges of behaviour change in circumstances of systemic social injustice and governmental mistrust, new approaches to evidence gathering were deployed. The SBST worked closely with community groups to develop detailed, qualitative insights into their perceptions of water use and the water crisis (Stillman, Reference Stillman2017). There was a clear sense in this situation that the gathering of trial-based, generalizable and quantitative data was neither feasible nor intellectually beneficial. It was clear that in trying to understand the contextual production of social injustice and suspicion at various local, state and federal levels, a more open-ended, ethnographic methodology needed to be deployed (context is thus not only important in terms of epistemological explanation, but also in terms of more mundane issues of methodological practice).
The work of the SBST in Flint is emblematic of a BPP initiative that is attempting to develop a more multifaceted understanding of the role of context in shaping human behaviour. This attempt reflects emerging work within human geography on the local production of systems of water cognition (Wolfe, Reference Wolfe2012), as well as work within anthropology on the creation of systems of local meaning and practice. To these ends, the SBST's research embodies a real world-inspired unbounding of the forms of interdisciplinary collaboration that have characterized BPP. This unbounding is, however, only partial. Although the SBST has sought to understand water behaviours in Flint through more in-depth study of how variously scaled economic, governmental and infrastructural processes have shaped community cognition, these insights have not been used to promote the development of more radically orientated contextual strategies for behaviour change. The SBST recommendations for behavioural policy in Flint ultimately saw a shift from multi-scalar contextual explanations of ‘irrational’ responses to water use advice in Flint to the more familiar use of local social and material contextual tools to promote desired behaviour. Thus, the SBST promoted the use of fairly routine ‘implementation prompts’ and ‘commitment devices’ for water filter use and replacement, ‘social norming’/peer pressure and greater policy transparency (to overcome mistrust) (Stillman, Reference Stillman2017). While these may be sensible contextual strategies in some ways, they tend to result in context moving from a multi-dimensional horizon for understanding human behaviour to more localized strategies for shifting said behaviours. So, ultimately, the SBST's work in Flint initially offered a more unbounded set of interdisciplinary perspectives on the contextual production of behavioural irrationalities, only to see context be wheeled out as a set of localized solutions to these irrationalities. The refocusing on local context in Flint is likely to offer only a short-term fix to problems of water behaviour (perhaps being no bad thing in the context of a public health crisis). More worrying, perhaps, is the fact that in seeking to correct irrational water behaviours, such work could undermine the political energy (and logic) that is encoded in these behaviours.
Discussion: obstacles and potential for a critical interdisciplinary agenda for BPP
In this paper, we have scrutinized the BPP movement in relation to its disciplinary orientations. We have argued that, despite widely shared celebrations of its ‘genuine’ interdisciplinarity (John, Reference John2018), this movement is actually often based on a bounded form of interdisciplinarity. In its boundedness, BPP is severely limited in its ability to take account of the holistic nature of contemporary policy issues. Hence, while it might make an innovative contribution to the established policy system, it is unlikely to become a standalone problem solver. As such, we have explored how the field could learn from insights from the more distant disciplinary perspectives of public administration and human geography and where it is already making such interdisciplinary excursions.
However, it is our contention that beyond fusions with human geography and public administration, there is a much wider interdisciplinary domain to explore for BPP. We envisage more disruptive interdisciplinary spaces in which fundamentally differing knowledge paradigms are confronted with one another (see Table 1). We would, for instance, see it as valuable if BPP would combine its micro-level psychologist's gaze with the macro-level perspective of the sociologist. Attempting to merge these gazes and their underlying paradigmatic views would undoubtedly raise conflict. One might even question whether such a merging is even truly possible without abandoning either paradigm. Shove (Reference Shove2010, p. 1279), for instance, firmly believes that such attempted interdisciplinary projects are ‘doomed to failure,’ reflecting a methodological naïveté concerning the incommensurable differences between, in her specific example, social practice theory and the behaviour change agenda. These approaches do not merely differ in their analytical gaze and instrumental kit, but already diverge in how they define policy problems (Shove, Reference Shove2010). We are, to some extent, sympathetic to this argument. Indeed, a puzzling question arises about where BPP might begin and end. How far could BPP go in a process of critical interdisciplinary engagement and still remain BPP? While acknowledging these ‘boundary issues’ (Ball & Feitsma, Reference Ball and Feitsma2018), we nonetheless would encourage attempts at exploring new interdisciplinary horizons and at least trying to develop critical interdisciplinarity. Even if a more disruptive interdisciplinarity would be hard to realize and also blur and break up BPP's identity, efforts to still try to live up to the ideal of critical interdisciplinarity as much as possible would seem to give the field the best chances at overcoming its own epistemological limitations.
Another legitimate question might be why it would be desirable to hold onto the label and paradigm of BPP in the first place, given its epistemological limitations. Why not move to a new paradigm altogether? We recognize at least two reasons to enrich and transform BPP from within, rather than trying to move beyond it. First, BPP still seems to be in a momentum of growth, as still more resources and support are being mobilized and new BPP programmes and units are being launched (John, Reference John2018). From an incrementalist point of view, it would seem more productive to go along with the current energy behind this institutional development and try to challenge and change it as it evolves further. Calling for a radically new post-BPP paradigm from an ivory tower position would seem less fruitful, not least because that would also prevent policy-makers from capitalizing on the unique epistemological benefits of BPP. Second, as BPP is still in a process of institutionalizing, now is a fertile moment to feed the field with new ideas from distant disciplinary perspectives. The field's early stage of development, not yet having matured and having settled its professional boundaries, comes with ample space for critical interdisciplinary inquiry.
Obviously, our attempt at outlining a critical interdisciplinary agenda for BPP in no way means that the field will actually engage with it. Rather, various institutional, political and cognitive reasons exist for the field sticking to its current body of interdisciplinary knowledge. A widely accepted way of interpreting emerging patterns of interdisciplinary engagement (and non-engagement) and bounding is provided by institutional perspectives (Jacobs & Frickel, Reference Jacobs and Frickel2009). From an institutional perspective, the nature of interdisciplinarity is understood to be facilitated and constrained by the organizational form of existing academic disciplines, labour markets, funding regimes and established channels of communication (MacLeod, Reference MacLeod2018; MacLeod & Nagatsu, Reference MacLeod and Nagatsu2018). Political reasons also partly explain the bounded interdisciplinarity of the field. As part of the waning neoliberal zeitgeist and in response to no longer maintainable welfare state systems, governments have constructed a new social state–citizen contract in which the responsibilities for social problems are increasingly shifted towards citizens (Ossewaarde, Reference Ossewaarde2007). Strong importance is attached to the notions of individual agency and choice. More bounded interdisciplinary strains of BPP are, in this light, politically appealing because they closely match this neoliberal narrative in terms of their methodologically individualist underpinnings (Shove, Reference Shove2010). It is also interesting to draw on the idea of ‘strategic ignorance’ here (McGoey, Reference McGoey2012). This notion refers to the usefulness of ‘knowing what not to know’ in the context of policy, as ‘not-knowing’ may allow actors to sidestep undesired accountabilities and responsibilities. In the case of BPP, we might observe a ‘strategic ignorance’, too. By not coming to ‘know’ the context at a structural level, the field legitimizes itself in not having to identify and intervene on such deeper-lying institutional, political, economic and socio-cultural factors affecting policy issues. BPP's bounded interdisciplinarity lies at the bottom of this ‘strategic ignorance’, acting as a legitimizing constrainer, helpfully narrowing down the field's disciplinary bounds and, with that, also its bounds of accountability and scope of intervention.Footnote 4
BPP's particular brand of (bounded) interdisciplinarity is not just a product of institutional and political dynamics, however. MacLeod (Reference MacLeod2018, p. 698) asserts that cognitive obstacles and the ‘domain specificity of expertise and scientific practice’ are what ultimately determine the success, failure and form of interdisciplinary endeavours. It is perhaps ironic that an appreciation of cognitive limitations should be so important to understanding the confines of a branch of interdisciplinary inquiry that is predicated on the study of cognitive limitations. But it is our contention, following MacLeod, that the bounded interdisciplinarity of BPP is to an important degree a product of the cognitive constraints that exist to effective forms of scientific collaboration. Academic forms of expertise are, in part, based upon systems of knowledge that are domain specific. Domain specificity does not necessarily correlate with disciplinary patterns of knowledge production, but forms of expertise that display:
(i)… narrow subject matter or classes of problems [that] cognitive systems address, and (ii) [an] inflexibility given the fine-tuned dedication and specialization of these systems to handling well that subject-matter alone. (MacLeod, Reference MacLeod2018, p. 703)
The fine-tuned specialization associated with domain specificity in turn reflects the simplification, or bounding, of complexity so that problems do not exceed the cognitive grasps of expertise (MacLeod, Reference MacLeod2018). Interestingly, theories of domain specificity are based upon similar assumptions regarding the cognitive forms of human judgements as those associated with BPP.
While domain specificity is often utilized to explain why interdisciplinary projects fail, it can also explain why others succeed. It is our contention that the constrained forms of interdisciplinary integration that characterize BPP can be partly explained on the basis of the ‘bounded habitats of knowledge practice’ (Knorr-Cetina, Reference Knorr-Cetina2007, p. 1) associated with domain specificity. To these ends, the coming together of cognitive psychology and economics within BPP does not reflect a form of inevitable interdisciplinary fusion in and through which the epistemological shortcomings of neoclassical economics are resolved in the only ways they could. The BPP movement embodies the emergence of new perspectives on the problem spaces of economics (specifically in relation to limited cognition, social influence and environmental influence), which are consistent with the domain specificity of economics. A more critical form of interdisciplinarity can avoid the limiting effects of scientific instrumentality through a focus ‘on the recognition of limits, defining how much or how little information is needed to address a challenge at hand’ (Frodeman & Mitchum, Reference Frodeman and Mitchum2007, p. 508). More critical interdisciplinarity thus seeks to endure beyond the initial interactions of interdisciplinary dialogue in order to consider not just whether disciplines can be usefully combined, but also to contemplate what other, potentially more challenging forms of knowledge and collaboration are needed to address the real-world problems towards which scientific endeavours are directed. It is in these contexts that interdisciplinarity can embrace more comprehensive and disruptive perspectives.
The BPP movement continues to gain traction in the global policy sphere. Meanwhile, ‘wicked problems’ persevere too, begging for more comprehensive interdisciplinary approaches. Our article has sought to connect these two developments. Let us see whether there is a future for BPP that is genuinely, and critically, interdisciplinary.
We would like to acknowledge the financial support of the Economic and Social Research Council (grant number: ES/L003082/1), the Leverhulme Trust and the NWO-TOP Research Project ‘Welfare Improvement through Nudging Knowledge’ (WINK). We are also grateful to Frank Mols and Michael Hallsworth, who provided comments on earlier drafts of this paper.