Forging a Universal Hammer? PPE as Analysis
“If all you have is a hammer, everything looks like a nail.”
Most of us in the Singaporean university context are familiar with the cautions against the narrow-mindedness of specialisation, and against wielding a single tool to approach every problem we may encounter. That is, to some extent, the draw of a cross-disciplinary programme like Philosophy, Politics, and Economics (PPE), which sets out to cultivate in students a broad range of methods and tools from the three disciplines with which to critically investigate social and political phenomena. But in some sense, are we attempting to forge a universal hammer, capable of fracturing any object of analysis into multiple dimensions no matter its substantive content?
In this article, I will sketch out one such view of PPE as a programme that attempts to build a comprehensive set of analytical tools and methods, fleshing out the value that each discipline brings to the table in turn. In the process, I will motivate the use of these tools in tackling problems of today, even as disciplines come into conflict over their differing conclusions on the same issue. Finally, I will demonstrate how we still have much to learn and borrow from disciplines outside the three, insofar as we are interested in PPE as a kind of social theorising with a strong grounding in the empirical.
Features of the universal hammer
Anything that throws light on its subject matter also casts shadows. So much is just in the nature of light. And those shadows cannot be dispersed simply by increasing the intensity of the light: doing that just makes the shadows deeper. Of course, if the intensity of the light is reduced, so is the capacity to see anything clearly. If you want to illuminate the shadows, you have to come at things from different perspectives: you have to shine some light, simultaneously, from different angles. And as every theatre-lighting engineer knows, in order to establish a shadow-free stage, you have to secure an appropriate balance among the various light sources. (Brennan & Sayre-McCord, 2022, p. 3)
The universal hammer is, before all else, a tool of analysis. This could mean several things, but as a first pass it is concerned with breaking down complex problems into smaller, comprehensible parts amenable to the methods of the individual disciplines. This also means that PPE employs analytic methods, which is reflected in both its orthodox form as a research programme and the nature of courses required at an undergraduate level—generally, PPE involves analytic philosophy and liberal (some say excessive) applications of formal models structured in the languages of first-order logic, calculus, linear algebra, and statistics.
That said, PPE can also be viewed as a project of synthetic philosophy—being an interdisciplinary enterprise, it comes as no surprise that marrying the three disciplines in intellectual union is just as important as enabling one to view a problem from three distinct perspectives. The hammer possesses some qualities that tools from the disciplines do not severally have: it is capable of both empirical and normative analysis, and being wielded comfortably across the realms of theory and praxis. Its centre of balance lies somewhere between the quantitative and qualitative approaches. So, it would seem right to conclude that PPE is as concerned with synthesis as it is with analysis; with putting together a comprehensive, coherent, and unified picture of the social world. This is what enables PPE to accurately diagnose (and to a lesser extent, tackle) wicked problems, for which there are often no precedents and obvious or easy solutions.
1. The unreasonably effective hammerhead of economic analysis
Predictably, the universal hammer I have in mind consists of three parts, and the most important part is arguably that which gives it the most force as a tool—the part which makes it a hammer to begin with. Naturally, this role is filled by economics, with its unreasonably powerful and vast range of analytical methods and models: cost-benefit analysis, game theoretic analysis, econometric modelling, social choice, public choice, and so on. The all but universal applicability of economic analysis is well-documented, with just about any social phenomenon being amenable to economic modelling. After all, “we live in a society”, so to speak, and any form of interaction with the social world can be scrutinised by an economist for as long as we are making decisions under scarcity (with the relevant assumptions).
Unlike philosophers, economists don’t seem to stop to think “is this economics?”, but rather “can we make this into economics?” (the answer is almost always “yes”). The generalisability of economic analysis helps it transcend disciplinary boundaries, expanding its domain of analysis beyond traditional questions of economics and into what is ordinarily the preserve of other disciplines in the humanities and social sciences. This voracious appetite is one of the strengths of making economics the hammerhead, and by extension the hammer a blunt instrument that can be brought to bear on just about anything—take for instance cliometrics, which has applied econometric techniques to studying history.
However, this same trait is not without controversy, having drawn accusations of economics imperialism from the disciplines it has invaded. While I think more plurality in the way we approach different problems in the social sciences never hurts, economic analysis could threaten this plurality in the long-term if its tools crowd out the methodologies of other fields. Furthermore, mainstream economics has also been criticised for its neoclassical assumptions, with charges that include flattening analytically rich agents into simplistic, constrained utility-maximisers animated by self-interest, as well as attempting to construct a value-free social science.
How might we resolve this? One obvious way is to expand our worldview to accommodate more pluralistic approaches, informed by the vast knowledge which lies outside disciplinary bounds. Philosopher and political economist John Maynard Keynes (1933/2010) writes that
the master-economist must [...] reach a high standard in several different directions and must combine talents not often found together. He must be mathematician, historian, statesman, philosopher—in some degree. He must understand symbols and speak in words. He must contemplate the particular in terms of the general, and touch abstract and concrete in the same flight of thought. He must study the present in the light of the past for the purposes of the future. No part of man's nature or his institutions must be entirely outside his regard. He must be purposeful and disinterested in a simultaneous mood; as aloof and incorruptible as an artist, yet sometimes as near to earth as a politician. (pp. 173–4, emphasis added)
In other words, economics alone is not enough, even as we turn the hammerhead towards issues that are typically not considered to be objects of economic analysis. As far as our hammer is concerned, economics constitutes a potent yet inert chunk of metal without the support of the other disciplines; our hammer is incomplete.
2. Ol’ reliable: the philosophical handle
What we need is a robust handle to hold up the hammerhead—to support and supplement the assumptions needed to operate it, or to stipulate suitable substitutes. No discipline is quite suited to this task as the oldest form of inquiry—philosophy. Philosophy remains expansive in its concerns as a field, even as the various disciplines that have sprung from it have gone on to systematise their own methods and objectives of inquiry. Still, the kind of philosophy we are concerned with in PPE is not everything under the sun, even if theoretically just about any aspect of philosophy (yes, even metaphysics) could potentially have distant relevance.
Instead, two main materials have been used to build our handle: the long tradition of moral philosophy in facilitating ethical reflection, and the resources of contemporary epistemology to accompany the shift towards analytic methods, in borrowing back tools from the social sciences. Specifically, we are interested in how these subfields intersect with social and political philosophy, which embody the bread-and-butter concerns of PPE.
Philosophy brings three distinct but interconnected things to the table:
Conceptual clarity. At a high level, philosophy provides the logical frame to understand and analyse abstract concepts. It achieves these through the use of various logics—propositional, first-order, and sometimes modal—to model the network of relationships among premises in a complex argument. With this, it becomes possible to identify necessary and sufficient conditions, cutting through the Gordian knots which frequently obfuscate the salient features of social phenomena.
Normative analysis. Moral philosophy adds a normative dimension to PPE analyses, allowing us to cross the chasm which typically separates fact and value. Through its concern for the right (“what does justice require?”) and the good (“what is of value?”), philosophy helps us critically examine the claims advanced by normative economics, and develops our own normative political theory in response. This serves not only to question the oversimplified judgements that often follow from utilitarian neoclassical analysis, but also to provide alternatives rooted in the rich traditions of other normative ethical thought such as deontology and virtue ethics.
Methodological reflection. Closely related to the above, philosophy facilitates reflection on the methods used by economics and the social sciences. This often involves questioning the rational choice theoretic assumptions which underpin most of modern economic theory, enhancing the standard picture of rationality, utility, and preference often taken for granted. Philosophy brings into sharp relief the departure from a realistic model of human behaviour, and invites a richer understanding by making space for heterodox theories and other disciplines.
Where does this leave us? It should be noted that the relationship between handle and hammerhead is not as straightforward as one of support. As one might glean from the foregoing, philosophy places the social sciences under tremendous tension by examining their core assumptions under critical lights. This tension is not easily resolved, but provides PPE with the starting point and resources to bridge the gap between what is and what ought to be; either reinforcing the conclusions derived through the social sciences, or contemplating feasible alternatives.
3. Getting a grip with political science
The hammer we have just described looks fairly complete—one powerful hammerhead, attached to one reliable handle. Taken together, philosophy and economics seem to provide a theoretical framework that is both analytically rigorous and broadly applicable in scope. It is for this reason that I concur with Dr Joel Chow’s remark that PPE is “most anchored” in these two disciplines.
While I have no doubt that many of the interesting questions we ponder in PPE emerge where both established modes of inquiry converge, there is still a sense in which something feels missing, a worry that this could be a bit too airy-fairy. For all the talk about markets, incentives, justice, and rights, have we been talking about real people so far, or idealised abstractions that still fail to capture the vast qualitative depth of individuals and society as a collective?
“The map is not the territory”, for sure, but there remain ways in which we can improve our model of the social world. The first way is to orient ourselves to our immediate environment, and better understand when it is appropriate to use our hammer, and when it is appropriate to set it aside for our screwdriver, instead. The second is to circumscribe the range of motion of our hammer, to get a firm grip on this powerful tool so we may apply it with exactly the right amount of force when we do choose to hammer things in.
Political science serves both these purposes. It provides a general starting point for the questions on the PPE agenda and on some restrictive accounts, delimits the issues of concern we apply our econo-philosophical tools to, namely social and political phenomena. In moving away from its philosophical roots, contemporary political science is, broadly speaking, committed to an empirical approach to investigating political affairs and the general business of organising society (though normative work remains, largely within political theory). This practical impulse is in some respects even stronger than that present in economics, and the way this informs PPE analysis is in the keen understanding of institutions which are neglected in orthodox economics approaches, but which nonetheless structure the choices of individuals in society (see Ostrom (1990), Governing the Commons; Acemoglu & Robinson (2012), Why Nations Fail). Political science also undertakes empirical qualitative work more readily than the other two disciplines, which has given us methods like ethnography to complement quantitative models. Finally, political science shines a light on the dynamics of power which pervade our interdependent relationships in society, complicating the notion of individuals as units of analysis. On the whole, political science can be understood as grounding PPE with a sharper and more complex picture of reality, enabling a more judicious use of its analytical tools to study the same phenomena of interest.
Wielding the universal hammer
With this, we thus complete a picture of our universal hammer—a robust hammerhead on a reliable handle, bound in a tight grip. It bears repeating that this is not the only account of what PPE is and what it sets out to do, but a brief sketch of it from the angle of building a powerful approach to analysis. In this regard, it might be overly narrow and prescriptive. Accounts like Hamlin’s (2010) provide a far more comprehensive (while still remarkably open-ended) overview of the themes which broadly characterise PPE, with the aim of moving from a theory of value to a theory of choice, or what he describes as “the winding road from good to right” (p. 370).
Returning to our concept of PPE as analysis, however, we should have strong reason to believe our general-purpose tool is well-suited for the problem it was made to tackle. Because Keynes (1931/2010) is so quotable, here’s another one from him giving a liberal’s description of the “general problem” I have in mind:
The political problem of mankind is to combine three things: economic efficiency, social justice and individual liberty. The first needs criticism, precaution, and technical knowledge; the second, an unselfish and enthusiastic spirit which loves the ordinary man; the third, tolerance, breadth, appreciation of the excellencies of variety and independence, which prefers, above everything, to give unhindered opportunity to the exceptional and to the aspiring. (p. 311)
One thing you can take away from this is that he sure was an Interdisciplinary Man™, through and through. The other, more readily apparent, is that the problems we seek to deal with involve many moving parts, and our solutions must be correspondingly sophisticated and pluralistic in approach, even if applying our tools may create contradictions. We must embrace the tensions that are created when the disciplines seem to come apart in the conclusion they arrive at, not just because it may be productive and satisfying to eventually reach a resolution, but also because this is often revealing about our own underlying assumptions (e.g. our value commitments in line with our political beliefs), and those of the disciplines at work.
Take for instance the case of the minimum wage policy, as a prospective student once raised to me at Open House; introductory economics will tell us that the minimum wage gives rise to unemployment as a form of price floor for the labour market, but this could run contrary to what justice requires as set out by theories of distribution in political philosophy seminars. Resolving this tension could mean insisting that moral and political imperatives override economic concerns, or re-evaluating the assumptions in mainstream economics about government intervention. Alternatively, it could mean setting out to validate theory with empirical data, and perhaps discovering that all things considered (as opposed to ceteris paribus), a minimum wage policy does not yield unemployment after all, maybe due to some concomitants like firms being already at minimum staffing, cultural attitudes, etc.
Overall, tensions between what the disciplines say can create difficulties, but also stimulate important and revealing discussion that reinvigorate investigations into theory. As such, while operating at the intersection of the three disciplines can be complicated at times, applying the tools may generate a far more useful analysis (and subsequent synthesis) than what can be achieved with one discipline alone. PPE still remains a suitably sophisticated tool to handle the increasingly intractable problems which might appear on the social landscape.
“Universal”?
A word of caution is in order concerning the “universality” of PPE as an analytic approach to social and political theory, both positive and normative. This anticipates criticisms of disciplinary imperialism like the kind economics has attracted, and was foreshadowed earlier by both Keynes’ vision of a master-economist and our concerns about a better map for the territory. To put it simply, there are still ways to improve our model!
There is no reason the desire to incorporate multidisciplinary perspectives and tools should stop with just the constituent disciplines of PPE. The three merely happen to form a convenient grouping as traditional aspects of political economy, and thus possess a shared history with a coherent(-ish) theme. There is still, however, much more for PPE to learn from other disciplines, and so any expectations of PPE as a universal hammer ought to be tempered at once.
This should not come as a surprise to anyone familiar with the humanities and social sciences; there has, in some sense, always been a shared goal of studying humans as social creatures, and thus a natural camaraderie and mutual interest among the disciplines in developing better ways of furthering that goal. Psychology is an obvious example, being a discipline that has systematically studied human motivations and behaviour. Contributions from psychology have led to the rise of behavioural economics, improving the descriptive fit of our model and opening up new possibilities (and some would say, a can of worms) for public policy. Law is another strong contender with strong ties to all three disciplines (I see you, PLE!), as it presents an applied view of how the rules of society are implemented and enforced in society. It demonstrates how a concern for justice rooted in theory might be actuated in practice under non-ideal conditions, shaping the incentive structures for citizens through institutions.
Moving from contextual understanding to methodological improvements, quantitative fields like data science and computing also have much to offer. The value they add to the modelling capabilities of an analytic programme like PPE grows continuously as the datasets we work with get increasingly bigger and less tractable with traditional statistical methods. In such cases, approaches like machine learning might prove useful in picking out non-linear patterns to improve high-dimensional models, although its use in econometrics is—as I’m aware—part of an ongoing debate. Quantitative fields also supply the background, theorems, and tools for formal approaches to philosophy and political theory, and provide new ways of approaching old problems like agent-based modelling. So, it goes without saying that PPE, being decidedly on the HSS side of the fence, will benefit a lot from looking to its STEM cousins in search of new ways of inquiry.
Conclusion
PPE, as illustrated in this article, represents a revival of an enterprise ripe with potential, prior to the specialisation which first drew up disciplinary boundaries. In painting it as a programme centred around building a coherent set of tools for analysis, this picture of interdisciplinary collaboration may risk being too optimistic in glossing over some of the difficulties and tensions that result from adopting different modes of thinking, that in many ways have departed significantly from the original strands of thought which animate the study of social and political phenomena. However, I hope to have provided some motivations for why it remains essential to keep these interdisciplinary conversations going to transform this diversity into strength, even as we remain wary about ascribing too much to PPE (and in general, interdisciplinary work). Achieving the elusive “targeted depth” in each discipline will be critical for us to gain a purchase on these tools without sliding towards dilettantism or imperialism, and without losing sight of how they all fit into the bigger picture.
Written by Austin Ho
Views expressed in this piece are solely the author’s own and do not represent those of the National University of Singapore or its affiliates.
References
Brennan, G., & Sayre-McCord, G. (2022). PPE as an Intellectual Enterprise. In The Routledge Handbook of Philosophy, Politics, and Economics. Routledge.
Hamlin, A. (2010). The PPE enterprise: A substantive research programme. Politics, Philosophy & Economics, 9(4), 366–378. https://doi.org/10.1177/1470594X09345679
Keynes, J. M. (2010). Liberalism and Labour. In J. M. Keynes (Ed.), Essays in Persuasion (pp. 307–311). Palgrave Macmillan UK. https://doi.org/10.1007/978-1-349-59072-8_23. (Original work published 1931)
Keynes, J. M. (2010). Alfred Marshall. In J. M. Keynes (Ed.), Essays in Biography (pp. 161–231). Palgrave Macmillan UK.https://doi.org/10.1007/978-1-349-59074-2_14. (Original work published 1933)