3.2: Refining the notions of ‘capability' and ‘functioning'

While at a very introductory level, the terms ‘functionings’ and ‘capability’ seem to be easy and straightforward, the terminology used in the literature is, alas, not always clear. There has been quite considerable confusion in the use of the terminology, although — if one takes a meta-disciplinary helicopter view — it is possible to discern that particular uses of certain terms are more dominant than others. The confusion has several sources. First, Amartya Sen and Martha Nussbaum have used the same terminology somewhat differently to each other, and since most capability scholars are more influenced either by Sen or by Nussbaum, its use in the wider literature is not standardised. Moreover, both Sen and Nussbaum have changed their use over time, without always making this explicit. Thirdly, there are differences in terminological choices that can be traced back to established differences in different disciplines, which are having their effect on the different disciplinary streams in the capability literature.

There are at least four terminological issues that need to be noted: (1) ‘capability’ understood as a single opportunity versus ‘capability’ understood as an opportunity set; (2) Nussbaum’s more complex terminology; (3) the quite different meanings given in the literature to the term ‘basic capabilities’; and (4) additional refinements — both some that have been proposed in the literature, as well as a proposal that I will put on the table, namely to take the robustness of a capability into account. Let’s look at these four issues in turn.

3.2.1 Capability as an opportunity versus capability as an opportunity set

Let us first look at Sen’s original terminology. The major constituents of the capability approach are functionings and capabilities. Functionings are the ‘beings and doings’ of a person, whereas a person’s capability is “the various combinations of functionings that a person can achieve. Capability is thus a set of combinations of functionings, reflecting the person’s freedom to lead one type of life or another” (Sen 1992a, 40). According to Sen, a person has only one capability (or capability set), which consists of a combination of possible, reachable functionings.

A person’s functionings and her capability are closely related but distinct, as the following quote illustrates:

A functioning is an achievement, whereas a capability is the ability to achieve. Functionings are, in a sense, more directly related to living conditions, since they are different aspects of living conditions. Capabilities, in contrast, are notions of freedom, in the positive sense: what real opportunities you have regarding the life you may lead. (Sen 1987, 36)

Sen thus used the term ‘a capability’ for what we could also call ‘a capability set’. The advantage of each person corresponds to one capability (hence ‘a person’s overall freedom to do the things they want to do and be the person they want to be’). In the original terminology, each person had one capability, and the use of the word ‘capabilities’ therefore had to refer to the capabilities of various persons.

In Sen’s original terminology, a person’s capability consisted of a range of potential functionings, out of which a particular combination of functionings could be chosen. Functionings could therefore be either potential or achieved. This kind of language is most familiar to social choice scholars and scholars in formal welfare economics, where the focus of much of the analysis is on the opportunity set.

However, many other scholars working on the capability paradigm, including Martha Nussbaum, have labelled these potential functionings ‘capabilities’, and only use the term ‘functioning’ for an outcome. In that terminology, the capability set consists of a number of capabilities, in the same way as a person’s overall freedom is made up of a number of more specific freedoms. One does not find this usage of ‘capabilities’ (meaning the separate elements of one person’s capability set) in Sen’s earlier writings, and in his later writings he (perhaps reluctantly) uses the word ‘capability’ in both senses interchangeably.

What, then, is the terminology that is now predominantly used? As was explained in chapter 2, a functioning is a state of one’s being (such as being healthy or ill), or something one is doing (such as going on a trip or raising children). The real opportunity to accomplish such a functioning, is the corresponding capability. Hence if my sister goes on a trip and invites me along, but I decide to stay at home because I want to do something else, then I have the capability to go on a trip, but I chose not to have the corresponding outcome — the functioning. Each functioning corresponds exactly to one capability.

This plural use of capabilities is widespread in the contemporary literature on the capability approach — with the exception of those working in social choice theory, formal welfare economics and related fields. The terminology as used by the broader group of scholars working on the capability approach seems to be more straightforward and less technical, but when reading Sen’s (earlier) work it is important to know that the term ‘capability’ started with a different definition.¹

3.2.2 Nussbaum’s terminology

In Women and Human Development, her first book-length work on her capabilities theory, Martha Nussbaum used the following terminology, which she still uses in her recent book on the capability approach (Nussbaum 2011, 20–25). Human capabilities are “what people are actually able to do and to be” (Nussbaum 2000, 5). From those human capabilities, Nussbaum identifies a list of ten “central capabilities” which have the status of rights: they “may not be infringed upon to pursue other types of social advantage” (Nussbaum 2000, 14). According to Nussbaum’s minimal account of social justice, these central capabilities have to be protected up to a certain threshold level.

Nussbaum helpfully distinguishes between three further notions to unpack the concept of ‘human capabilities’: basic capabilities, internal capabilities, and combined capabilities (Nussbaum 2000, 84–85). The term basic capabilities refers to “the innate equipment of individuals that is necessary for developing the more advanced capabilities”, such as the capability of speech and language, which is present in a new-born but needs to be fostered before it can develop into a true capability. Internal capabilities are “the matured conditions of readiness” — the internal aspect of the capability. If I have the skill and meet the physical preconditions of walking, then I may or may not be able to go for a walk — depending, for example, on whether as a woman I am legally allowed to leave the house without a male relative, or whether there is not currently a hurricane posing a real danger if I were to leave my house. If those suitable external conditions are in place, we can speak of combined capabilities.

Finally, a functioning is an “active realisation of one or more capabilities. […] Functionings are beings and doings that are the outgrowths or realizations of capabilities” (Nussbaum 2011, 25). Hence, in Nussbaum’s terminology, a functioning stands in relation to a capability as an outcome stands in relation to an opportunity.

While the substantive distinctions to which Nussbaum’s terminology refers are very helpful, the specific words chosen may be not ideal. There are two problems. First, for many capability scholars, the reference to the term ‘capability’ refers to the real opportunity to do something or be the person one wants to be; ‘internal capabilities’ do not fit that category. They are, starting from that perspective, simply not a capability, but rather necessary elements of a capability, or a precondition for a capability. It would have been better to call ‘internal capabilities’ simply ‘internal characteristics’ or else ‘skills, talents, character traits and abilities’. Such terminology would also make the link with various other behavioural and social disciplines much easier. What Nussbaum calls ‘combined capabilities’ could then simply be called ‘human capabilities’, which consist of the presence of those skills, talents, character traits and abilities, together with suitable external conditions and circumstances. Second, Nussbaum uses the term ‘basic capability’ after it had already been used in two other different ways, as the next section will show. Why not simply call these ‘innate human characteristics’?

3.2.3 What are ‘basic capabilities’?

The way readers from different disciplines use terminology in particular ways is clearly exemplified by the various interpretations of the term ‘basic capabilities’.

One interpretation is Nussbaum’s. As was mentioned before, Nussbaum (2000, 84) uses the term ‘basic capabilities’ to refer to “the innate equipment of individuals that is necessary for developing the more advanced capabilities”, such as the capability of speech and language, which is present in a new-born but needs to be fostered. Yet of the four ways in which the term ‘basic capabilities’ is used in the literature, this one may be the least prevalent.

Sen (1980) mentioned the term ‘basic capability’ as his first rough attempt to answer the ‘equality of what?’ question, but changed his terminology in subsequent work (what he called ‘basic capability’ would later become ‘capability’).² In his later writings, Sen reserved the term ‘basic capabilities’ to refer to a threshold level for the relevant capabilities. A basic capability is “the ability to satisfy certain elementary and crucially important functionings up to certain levels” (Sen 1992a, 45 fn 19). Basic capabilities refer to the freedom to do some basic things considered necessary for survival and to avoid or escape poverty or other serious deprivations. The relevance of basic capabilities is “not so much in ranking living standards, but in deciding on a cut-off point for the purpose of assessing poverty and deprivation” (Sen 1987, 109).

A third way in which the term ‘basic capabilities’ can be used is, as in analytical political philosophy, to refer to essential (moral and/or political) entitlements that signify a higher level of moral urgency, according to the philosopher’s own normative commitments. For example, Rutger Claassen, who has been developing an agency-based capability theory of justice, has been using the term ‘basic’ in that sense (Claassen 2016).

A fourth way to use the term ‘basic capability’ has been proposed by Bernard Williams. Yet this has, to the best of my knowledge, not been taken up by anyone. Williams has argued that it is important to distinguish between the capability to choose yet another new brand of washing powder from, say, Adam Smith’s often-cited capability to appear in public without shame. Williams rightly notes that “what you need, in order to appear without shame in public, differs depending on where you are, but there is an invariant capability here, namely that of appearing in public without shame. This underlying capability is more basic” (Williams 1987, 101). I agree with the need for the distinction that Williams makes, but I would rather call these underlying capabilities the general capabilities, so as to avoid confusion with Sen’s use of basic capabilities. I will turn to the discussion of general versus specific capabilities in section 3.2.4, but first I want to ask the question: how should we interpret the term ‘basic capability’?

My reading is that, within the capability literature, the most widespread (and hence dominant) use of ‘basic capabilities’ is Sen’s use, referring to poverty or deprivation. Hence, while the notion of capabilities refers to a very broad range of opportunities, ‘basic capabilities’ refers to the real opportunity to avoid poverty or to meet or exceed a threshold of wellbeing. By focusing on ‘basic’ capabilities, we are limiting the set of all capabilities in two ways: first, by having a selection of capabilities (i.e. those that are key to capturing wellbeing, and those that are centrally important), and second, by imposing a threshold at which those capabilities will be evaluated (i.e. at a low or poverty-like level).

Basic capabilities are thus crucial for poverty analysis and in general for studying the wellbeing of large sections of the population in poor countries, or for theories of justice that endorse sufficiency as their distributive rule. In affluent countries, by contrast, wellbeing analysis often focuses on capabilities that are less necessary both for survival and the avoidance of poverty. It is important to acknowledge that the capability approach is not restricted to poverty and deprivation analysis but can also serve as a framework for, say, project or policy evaluations or inequality measurement in non-poor communities. Sen’s and Nussbaum’s extensive writings on the capability approach in the context of poverty alleviation and development questions have misled some of their readers into thinking that the capability approach is about poverty and development issues only. Yet as has been absolutely clear from the description and account of the capability approach presented in chapters 1 and 2, there is conceptually or normatively no reason to restrict its scope in this way. The term ‘basic capabilities’ is helpful since it can signal to the reader when the capability approach is specifically used in this context.

3.2.4 Conceptual and terminological refinements

Over the years, several proposals have been made to refine the notions of ‘functioning’ and ‘capability’, or to add additional qualifications which may be helpful in capability analyses.

The first refinement — which is straightforward but still very helpful — is the distinction between general and specific functionings and capabilities (Alkire 2002, 31). Suppose we are concerned with questions about what is needed for people not to be socially excluded. Sen has repeatedly referred to Adam Smith’s example that, in order to be able to appear in public without shame, one needed (in the time and place Smith lived) a linen shirt. Yet in other countries one would need a sari, or a suit, or something else. We all know that in every specific time and place, there are certain types of clothes one shouldn’t wear if one doesn’t want to be frowned upon or be seen as inappropriately dressed. We could say that, for women in place A, being able to wear a sari is important, and for men in another place, being able to wear a suit is important, in order not to be excluded. ‘Being able to wear a sari’ and ‘being able to wear a suit’ are specific capabilities; ‘being able to wear the clothes that are considered appropriate’ is the more general capability. Thus, if we formulate the relevant capabilities at a higher level of generality, it will be easier to reach agreement on what those are, than if we focus on more specific capabilities (Sen 1992a, 108–09). General capabilities are thus the more generic and more abstract capabilities. The idea of general versus more specific functionings and capabilities is also entailed by Nussbaum’s idea of the multiple realisability of capabilities that are under scrutiny: the selected capabilities “can be more concretely specified in accordance with local beliefs and circumstances” (Nussbaum 2000, 77).

A second conceptual refinement to consider is the concept of ‘refined functioning’. Sen (1987, 36–37) has proposed the concept of ‘refined functioning’ to designate functioning that takes note of the available alternatives. Sen (1992a, 52) notes: “‘fasting’ as a functioning is not just starving; it is choosing to starve when one does have other options”. The aim of this proposal is to try to bridge the choice between functionings and capabilities by a conceptual move. That is, one could focus on achieved functionings levels but — where appropriate — include the exercise of choice as one of the relevant functionings (Fleurbaey 2002). This allows us to stay within the realm of (observable) achievements, but because the act of choosing is included, one can derive from that functioning relevant information about whether one had options or not.

A third conceptual refinement — this time a qualification or property that we can attribute to a functioning or a capability — has been proposed by Avner De-Shalit and Jonathan Wolff. They have argued that what is relevant for the most disadvantaged persons is not so much whether they have any functionings, but rather whether those functionings are secure (Wolff and De-Shalit 2007, 2013). The idea here is that we are not only interested in the functionings that people can achieve, but also in the prospects that a person has to sustain that level — that is, the risk and vulnerability of losing that functionings achievement should be taken into account, even if the risk never materialises. The objective fact of risk and vulnerability itself should be seen as having an influence on how we normatively judge a functionings achievement (Wolff and De-Shalit 2007, 63–73).

Another qualification that we could add to capabilities is their robustness — referring to the probability of a capability being realisable. The standard definition of a capability is that it is a genuine option: if we have the capability and we choose this opportunity, then we should also enjoy the outcome — the functioning. But this presents us with a very dichotomous view of our options: either we have an option with a 100% probability, or else, if the probability is significantly less, it is implied that we do not have the capability. That is, arguably, a rather unhelpful way of thinking about real life processes. For example, the problem with women’s opportunities in advanced economies is definitely not that women have no capabilities to achieve professional success; rather, the problem is that, given a variety of mechanisms that are biased against female professionals, the robustness of the capabilities they are given is weaker. If an equally talented man and woman both want to succeed professionally, they may, in a liberal society, both have that capability — but the probability that the man will be able to succeed will be higher than the woman’s. She does have some opportunity, but that opportunity is less robust. Probabilities of success if one were to want to exercise that capability would be a way to express this. In the above gender case, the source of the different probabilities lies in the social and environmental conversion factors. But the source of the difference in robustness could also lie in internal factors. For example, a person with a psychiatric condition may have some opportunities for finding a job, but those opportunities may be much more precarious then they would be if she didn’t have those psychiatric challenges.

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1 For a seminal analysis of the differences between Nussbaum’s and Sen’s conceptual and terminological apparatus, see the twin papers by David A. Crocker (1992, 1995).

2 The ‘equality of what?’ debate was prompted by Sen’s Tanner lecture with the same title (Sen 1980a), in which he argued that almost any theory of distributive justice is egalitarian, in the sense that they all advocate equality of something. The question to pose to a theory of distributive justice is therefore not whether it is egalitarian or not, but what is its answer to the ‘equality of what?’ question.