Collective Action and Social Ontology in Thomas Aquinas

2.1 General Principles

Many commentators have noted that Aquinas’ doctrine of intentionality raises significant difficulties for modern readers given its reliance upon classical Aristotelian metaphysical categories such as, e.g., the principles of act and potency, form and matter, etc. (Anscombe and Geach 1961; Haldane 2010; Kenny 1994; Lisska 2016). In fact, perhaps the most important thing to recognize about Aquinas’ doctrine of intentionality, generally, is that it is above all else a metaphysics of mind. That is to say, rather than conceiving of the “philosophy of mind” as a more or less unique philosophical discipline that involves its own distinctive principles and categories, Aquinas’ approach instead operates on the assumption that intentionality is first and foremost the unique mode of existence enjoyed by objects insofar as they are perceived and known—what Aquinas calls “intentional existence” (esse intentionale).^[4] To have an account of intentionality in light of Aquinas’ approach, then, is to have a metaphysics of intentional existence—an “ontology of the knowing [intentional] situation” (Lisska 2016, p. 33). In short, the principles undergirding Aquinas’ account of collective action are general metaphysical principles, albeit applied to the context of intentional agents.

For Aquinas, a person’s identity endures over time by virtue of her soul, which is understood as the substantial form of the body. The soul’s powers together account for the distinctive acts proper to a human form of life (Sent. De An., I.14).^[5] The most important of these distinctively human powers for our purposes is “will” (voluntas), since it is the individual’s person’s will that is the ultimate subject of her collective acts. At the most general level, the characteristic act of will is “desire” (appetere), which encompasses many other intentions and acts which, taken together, constitute a lifelong, ecstatic inclination toward its ultimate end: namely, “happiness” (beatitudo) (S.th., 1-2.2.8c). This is Aquinas’ “big picture” of intentional action, and it is from this larger picture that individual intentions and acts are ultimately individuated as parts.

Note that it is desire—not “choice,” construed as spontaneous movement toward one or more “options”—that is the most fundamental act of will here.^[6] The primacy of desire with respect to choice undergirds his position that intended ends are (final) causes of individual intentions and actions (S.th., 1.82.4c). Even if the will is relatively “self-moving” as compared to bodily passions (S.th., 1.82.2 ad 3), its individual acts of desire are nevertheless specified by their objects or ends. Thus, according to Aquinas, it is of course true that I am perfectly capable of “choosing” one or more options from a dinner menu, but only insofar as I understand my chosen meal as good, i.e., as the end of my particular act of desire (S.th., 1.82.4 ad 3). If there were no object presented to the will as desirable, there would be no corresponding act or the will's desire ends (S.th., 1.77.3c).

However, reasons Aquinas, because we do not obtain our various desired ends immediately, we are in need of means. This leads us to Aquinas’ doctrine of intentional action. Properly speaking, for Aquinas, the will’s act of intending (intendere) is uniquely characterized by its “tending toward” an end by means of something else (S.th., 1-2.12.1 ad 4). It is precisely this act of ordering means to ends that constitutes intending, in Aquinas’ sense.^[7] At the restaurant, again, there is a sense in which I desire a falafel salad absolutely; however, more specifically on Aquinas’ analysis, I intend the falafel salad (i.e., to consume it) to the extent that I make use of my various means of obtaining it (e.g., using language for the purposes of ordering, my implicit agreement to pay for the meal, etc.).

Now of course it is also the case that I also intend some other end for which the falafel salad is chosen as a means (e.g., a pleasant dining experience, bodily health, etc.), but the falafel salad is not both a means and an end in some sort of contradictory sense. Rather, in such a case, there are simply two distinct ends in one larger “order” of intention (see S.th., 1-2.12.3c).

So the soul’s power of will is specified by its distinctive acts, and acts are in turn specified by their distinctive objects or ends. But there remains one more core principle in Aquinas’ schema that is especially important for his account of collective action: namely, the concept of virtue (virtus). For Aquinas virtues are habits that play a direct role in the moral growth of human beings (S.th., 1-2.55.1sc). They are patterns of human desire and intention that are built up over time by successive choices. They order the subject’s passions, practical understanding, and choices in psychologically healthy ways (cf. Annas 2003).^[8] In short, they are principles of right living—comparable to what we today might characterize as practical expertise or “skill” (e.g., in music, painting, sports, etc.) in that they amount to a sort of skillful ordering of means to ends. Unlike intentional powers such as intellect and will, virtues do not follow upon the “natural” necessity of human nature as such (S.th., 1-2.55.1). Rather, they have to be acquired through successive choices that we may or may not make. As it happens, these properties make virtue—distinct from powers and acts—a good candidate for the primary locus of collective action insofar as acting qua a member of a particular group requires habituation into one’s role or function in the context of a social group’s distinctive common good. In other words, on Aquinas’ analysis, what it takes for a soldier, citizen or family member to act collectively is precisely to acquire and develop the virtues necessary for her function as part of her social group. As we will see, Aquinas’ notion of virtue plays a role similar to what some contemporary philosophers (Epstein 2015; Tuomela 2013) have called the “social glue” binding groups together in a way that is (in paradigmatic cases, at least) not easily broken.

In fact, even if virtues are built up by successive choices, it is important that they are not just identical with those choices considered as an aggregate. In fact, says Aquinas, the most important feature of virtue is that it is a principle of action (S.th., 1-2.55.2 ad 1) insofar as it “makes for an ordered operation” (facit operationem ordinatum) in the agent who has acquired the virtue. In other words, once acquired, virtues play a causal role with respect to virtuous acts. So virtues are effects of successive intentional acts in that the latter are necessary conditions for the acquisition of the former. But virtues are causes of in that they condition the “mode of action” (modus actionis) of the agent (S.th., 1-2.55.2 ad 1) once they are acquired. It is this “mode of action” that distinguishes virtuous acts from acts that merely happen to be good (QD de Virt. 1.9 ad 13).^[9] For, unlike such merely good acts, a virtuous act is systematically related to the acquisition of habits acquired by successive choices in a given domain of moral experience.

We can tell the difference between merely good and virtuous acts, says Aquinas, by identifying the latter’s proper mode of action: “before acquiring the habit of virtue someone does not do the works of virtue as the virtuous one does, namely, promptly and without doubt and with pleasure and easily” (QD de Virt. 1.9 ad 13). The upshot here is that virtuous acts are not a distinct species of intentional act; rather, they are virtuous because of the mode in which they are carried out, i.e., with assurance, pleasure and ease. It is this mode of action that is the primary “evidence” of the act’s being an effect of virtue.^[10]

For Aquinas, then, virtues are habits that play an integral role in the desires, practical self-understanding and acts that, together, constitute a lifelong process of moral formation. Virtues are not natural capacities, and so they have to be acquired by skilled habituation (S.th., 1-2.66.1-2). However, virtues are nevertheless principles of desiring, intending and acting insofar as they dispose their respective powers to perform such operations in a virtuous mode.

So Aquinas’ account of intentional action involves four main metaphysical building blocks: (1) intentional powers such as the will, which are the proper causes of intentional acts; (2) intentional acts such as desiring and choosing, which are specified by their distinctive objects or ends; (3) intentional objects such as the consumption of food or a sonata successfully played, which serve as final causes for intentional acts; and finally (4) virtues, which condition the unique mode in which intentional acts are carried out. But if this brief sketch concerns Aquinas’ account of intentional action in general, what about collective intentional action? After all, the abovementioned “Central Problem” of collective intentionality concerns the way in which individuals intend and act as members of social groups. Aquinas’ answer, I argue, comes in the form of an analysis of the notion of “general virtue”: properly collective intentional acts are those conditioned by general virtues. Therefore we now turn to Aquinas’ distinction between “specific” and “general” virtue, with special reference to the virtue of justitia as a case study.

2.2 General Virtue and Collective Action

So virtues are principles of acting in that they are acquired habits in the exercise of a given power. In short, to desire, intend and act virtuously is to do so in a “skilled” mode. Yet this on its own is not enough to account for the primary desideratum collective action: namely, the aforementioned phenomenon of intending and acting together.

Specific virtue (virtus specialis) is more familiar in popular renderings of virtue ethics than is general virtue (virtus generalis). Specific virtues are habits pertaining to the moral formation of individuals qua individuals. Like all virtues, they are specified by their distinctive acts, which are in turn specified by their objects. The virtues of temperance and courage are good examples of specific virtues, since they pertain to operations individuated by specific domains of human moral experience—in this case, the healthy management of pleasure and fear, respectively.^[11]

General virtues are different—and importantly so, for the discussion of collective action. Although they are also specified by their object, general virtues are unlike specific virtues in that they pertain not to one specific domain of moral experience among others, but rather to the whole of human moral experience insofar as it can be ordered to the common good of a given social group. This is important for our thesis, since the common good turns out to be the ordering principle of collective action in Aquinas’ schema.

In order to appreciate this point, we turn to the discussion of justice in Summa theologiae 2-2.58.6, in which Aquinas details what makes general virtue “general”:

A thing is said to be ‘general’ in two ways. First, by predication [per praedicationem]: thus ‘animal’ is general in relation to ‘man’ and ‘horse’ and the like…. Secondly, a thing is said to be general according to power [secundum virtutem]; thus, a universal cause is general in relation to all its effects. (S.th., 2-2.58.6c)

The former meaning of “general” is not relevant here. Virtus generalis is not a “genus” or “set” to which specific virtues such as temperance and courage belong as species or members. Instead, the way in which a given virtus generalis is “general” with respect to specific virtues concerns generality “according to power” (secundum virtutem)—that is, as a principle is general with respect to that of which it is the principle (Sent. Pol., III.3.7). Other examples of this sort of generality include the way in which a Euclidean point is general with respect to a line, or indeed the way in which God is general with respect to his creation (In Met., XII.12.37). That is, something is general secundum virtutem if it stands to what is specific as a formal condition of possibility and ordering principle. Without Euclidean points, a line cannot exist; without God, creation cannot exist; and, in the same way, without general virtue, specific virtue cannot exist.

This formal point about generality is illustrated in Aquinas’ rendering of the traditional Aristotelian distinction between general and particular justice.^[12] On the one hand, all forms of justice are properly “social” in the sense that all just acts are acts that render unto another her right according to some mode of equality (S.th., 2-2.58.2). The nub of the distinction between particular and general justice, however, has to do with its proper object. As Aquinas remarks in the previous article,

Justice … orders someone in relation to others. Now this may happen in two ways: first, as regards his relation with individuals; second, as regards his relations with others in general, insofar someone serves a community, serves all those who are included in that community.… Now it is evident that all who are included in a community stand in relation to that community as parts to a whole; while a part, as such, belongs to a whole, so that whatever is the good of a part can be directed to the good of the whole. It follows therefore that the good of any virtue, whether such virtue directs one in relation to oneself, or in relation to certain other individual persons, is referable to the common good, to which justice directs: so that all acts of virtue can pertain to justice, in so far as it directs one to the common good. It is in this sense that justice is called a general virtue. (S.th., 2-2.58.5c)

This passage gets to the heart of Aquinas’ account of justice, and general virtue, by extension. Particular or “specific” justice is that habit of will by which we relate ourselves to others in a way that is befitting to the respective dignity of other individual members of society (S.th., 2-2.61.1). Acts of “commutative” justice are paradigmatic in this regard, since commutative justice “consists in mutual dealings between two [or more] persons” in such a way as to be “blind” to social status, honor or other qualities intelligible only in light of a given social group. Acts of commutative justice include, for example, economic transactions that are obedient to some sort of “just price,” i.e., a price that adequately reflects the respective needs of individual buyers and sellers in a marketplace (S.th., 2-2.77.1). Still, ultimately the virtue of specific or particular justice pertains to the perfection of oneself, i.e., insofar as one’s moral perfection must include one’s ability to relate oneself unto others in accordance with their dignity as persons.

General justice is importantly different. It too orders acts as they pertain to the respective dignity of others. Yet it does so not qua individual, but rather qua part of a social whole.^[13] This point lies behind an oft-made refrain in the Aristotelian tradition: “the virtue of the good [individual] is not the same (simpliciter) as the virtue of the good citizen” (S.th., 2-2.58.6sc). Whereas acts of commutative justice belong properly to individuals, acts of general justice belong properly to citizens, i.e., parts of a social whole. In other words, general justice is the acquired habit that is an individual’s functional membership in a community. In the next section, I will work to get clearer about the precise sense in which individual citizens (and various institutions comprising the political community) can be called “parts” belonging to a properly social “whole”.^[14]

As the aforementioned passage indicates, it is because the common good orders individual goods as their principle and their end that general virtue is general. This is the sense in which collective acts are collective, i.e., insofar as they are causally conditioned by general virtues. While the same (specific) acts might be individual or collective in a given context, the “together-ness” of collective action lies in its uniquely social mode—that is, a mode of action conditioned by general virtue and thus ordered to the common good, which among other things is the collective good of a given social whole that relevant individuals intend as parts.^[15]

2.3 The Individual Ownership Claim

So the basic building blocks of Aquinas’ theory of intentional action in general are powers, acts and objects. Powers are specified by their distinctive acts, and acts are specified by their distinctive objects or ends. However, in addition to these building blocks, there is the “intermediate” principle of virtue, which I have defined as an acquired habit that plays a causal role with respect to properly virtuous acts. But virtues are specific and general. Unlike specific virtues, which concern one specific domain of moral experience, general virtue is marked by a person’s acquired ability to order the entirety of her intentional acts to the common good insofar as she is part of some social group. It is this modality of intentional action that makes it “collective” in the relevant sense.

It should be noted that all four of these building blocks are properties of individual souls, not groups. Only individual souls have wills, and so ultimately the intentional acts that proceed therefrom by way of efficient causality are proper to those individuals. Thus even collective action—i.e., acts produced by general virtues—are carried out by individuals with the relevant virtues. An individual group member who acts for the common good of a social group does not cease to be an individual—even when she is acting qua part of a social whole.

Therefore Aquinas can affirm that it is the individual group member who acquires general virtue, and thus also engages in collective action. There is no danger of positing a single group hive mind or otherwise violating the theoretical constraint set by the Individual Ownership Claim. However, as I will now try to show, there is also a sense in which Aquinas’ account of collective action is also anti-reductionist in its implications for the ontology and agency of social groups considered as objects in their own right.

3.1 Social Groups as Heterogenous Wholes

An important position that Aquinas endorses with respect to the ontological constitution of social groups is that they are “heterogenous” rather than “homogenous” wholes (S.th., 1.11.2). Responding to an objection arising out of the commentary tradition on Aristotle’s Metaphysics, Aquinas remarks,

There are two kinds of whole: namely, (1) the homogenous whole, which is composed of similar parts; and (2) the heterogenous whole, which is composed of dissimilar parts. For in any given homogenous whole, the whole is constituted by parts having the form of the whole, just as every part of water is water…. [By contrast] in any given heterogenous whole, every part is lacking in the form of the whole, for no part of a house is a house, and neither is any part of a human a human. (S.th., 1.11.2 ad 2)

Here Aquinas notes two features proper to homogenous and heterogenous wholes, respectively. First, the parts of homogenous wholes are “similar” in the sense that they share the same form. “Every part of [a given amount of] water is water,” he remarks, because each part of the given amount is identical in terms of its substantial form. By contrast, the parts of heterogenous wholes are “dissimilar” in the sense that they do not share the same form. The parts of a house (e.g., floor, walls and roof) are formally distinct from one another. That is to say, the parts of heterogenous wholes are different kinds of thing.

The second distinctive feature of homogenous and heterogenous wholes again pertains to the formal diversity of parts—not just with respect to each other, but with respect to the form of the whole. In homogenous wholes (e.g., the given amount of water), parts share the form of the whole. That is, in the given amount of water, the form of the entire amount is again identical to the form of the “parts” of the amount. In heterogenous wholes (e.g., the house), by contrast, parts lack the form of the whole. Walls and roofs are not houses. Only in homogenous wholes is the whole “predicable of the parts”. Aquinas takes this observation to imply that the distinctive integrity of the heterogenous whole is something qualitatively “new” or “emergent” with respect to its parts—a position that is further justified by the whole’s “emergent” powers or features that are not proper to the parts (Stump 2006).

This technical distinction at the level of general metaphysics is important for Aquinas’ social ontology. Indeed, he explicitly holds that some human communities are indeed heterogenous—not homogenous—wholes. In his commentary on a suggestive, yet relatively undeveloped passage in Book III of Aristotle’s Politics, Aquinas goes beyond the letter of the text in order to “clarify” (i.e., creatively interpret) the Philosopher’s abovementioned claim that the virtue of the good individual person is not simpliciter the same as the virtue of the good citizen.

[Aristotle] says that every city consists of heterogeneous parts, just as an animal is composed of dissimilar parts: namely, soul and body. And similarly, the human soul consists of dissimilar parts: namely, rational and appetitive powers. Indeed, the domestic society consists of dissimilar parts: namely, man and woman, and [the art of] possession requires a master and a slave. But the city consists of all these diverse parts and many others. (Sent. Pol., III.3.4)

There are at least two important implications of this passage. First, although he is obviously referencing the work of Aristotle, Aquinas appropriates the aforementioned distinction between homogenous and heterogenous wholes, holding that the political community is a heterogenous whole in precisely the aforementioned sense. That is to say, the political community considered as a whole (a) contains parts that are formally distinct from one another and of the whole (e.g., man and woman; master and slave); and therefore also (b) emergent powers and acts. While this may already be a plausible implication of the Aristotelian text, it is notable that Aquinas is using his own distinction to interpret the view—a view that he clearly holds himself in other non-commentary texts (e.g., De Reg., I.1.9).

The second important implication is that Aquinas clearly holds that the heterogeneity of the civitas as a whole—and therefore its distinctive formal integrity—is generalizable in the sense that at least some other human communities (e.g., domestic societies) also enjoy this special mode of unity (see Pakaluk 2001, p. 66 and the discussion below).

Finally, the third important implication of this passage is its relative indifference with respect to the question of whether the wholes at issue are “natural” or “artificial”. This is evident in the passage cited in the sense that Aquinas holds that slavery as an institution is not grounded in “natural law,” but rather “consequent utility” (utilitatem consequentem) following some particular social arrangement.^[16] Therefore, at least to the extent that this commentary represents his own view,^[17] Aquinas appears to hold that even artificial wholes are heterogenous and thus emergent. This is obviously an important claim for the purposes of understanding Aquinas’ social ontology, since most social groups—though perhaps not all—are “ontologically subjective” in the sense that their emergent being and powers are constituted (at least in part) by the creative capacities of human intentionality.^[18]

So Aquinas explicitly holds that social groups are heterogenous wholes, which is again to say that they are constituted by parts that are formally distinct from other parts and from the whole. In short, regardless of whether they are artificial or natural, social groups have irreducible powers and acts and are, therefore, “emergent” in a strong sense.^[19] However, this begs a further question: if indeed social groups are heterogenous wholes with irreducible, emergent forms, what is distinctive about the end or “final cause” to which such entities are ordered? The answer to this question lies with the Aquinas’ aforementioned Aristotelian conviction that “the virtue of the good [individual] person is not the same (simpliciter)as the virtue of the good citizen”.

3.2 Emergent Powers of Social Groups

We have already seen that Aquinas’ account of the virtue of justitia generalis is distinct from other virtues on account of the end to which it is ordered: namely, the common good. Yet we have said little about this slippery notion. What does Aquinas mean by bonum commune, and what could it mean to say that it is formally distinct from the respective goods of individuals?

Perhaps the best way to approach this question, initially, is to consider a qualification Aquinas offers to his abovementioned point about social groups being heterogenous wholes. Commenting on Book 1 of Aristotle’s Nicomachean Ethics, Aquinas says the following:

It is known that this whole, i.e., the civil multitude or domestic family, only has a unity of order, according to which it is not something one simpliciter. And thus a part of this whole can have an operation that is not the operation of the whole, just as a soldier in an exercise has an operation which does not belong to the whole exercise. (In Nic. Ethics, I.1.5)^[20]

So, while both social groups and human bodies enjoy the distinction of being heterogenous or emergent wholes, they do so in different ways. Unlike proper substances such as human beings, which are “one simpliciter”, the formal intelligibility and, therefore, the particular acts performed by individuals constituting a social group are not necessarily attributable to the whole (see discussion in Keys 2006, p. 85). In short, while social groups are indeed heterogenous and therefore emergent unities, they are so only “relatively” (secundum quid), not “simply speaking” (simpliciter).^[21]

Indeed, as one might anticipate given the brevity of the passage, the exact sense in which social groups are irreducible in Aquinas is unclear. Mary Keys (2006, p. 85), following others such as Russell Hittinger (2007, p. 271), infers from this point that a social group “is not understood by Aquinas as an organism or a thing but rather, most fundamentally, as an association whose unity comes from human action and interaction, and from common action with a view to a common end or ends”.

Yet, even on these commentators’ own terms, it is not clear how social groups could fail to be things in some sense.^[22] After all, the very next point Aquinas makes in the same passage of his Nicomachean Ethics Commentary is that “this whole [i.e., the whole social group] does have an operation that is not proper to its parts but to the whole—for example, an assault of the entire army” (In Nic. Ethics, I.1.5). Crucially, for Aquinas, only armies carry out “assaults”—not individual soldiers qua individuals, however mighty they may be. If there is a clear sense in which a social group is a unique or qualified heterogenous whole, there can be no denying that Aquinas holds that social groups are not only things, but agents. Indeed, the Nicomachean Ethics Commentary is clearer on this point than even the Politics Commentary.^[23]

It is precisely this point—namely, that social groups have emergent powers and acts—that occasions the question of whether the common good is formally distinct from individual goods. Aquinas puts the matter succinctly: “The common good of the city and the good of one singular person differ not only in accordance of ‘many’ and ‘few’, but rather according to a formal difference” (S.th., 2-2.58.7 ad 2). That is to say, because citizens are parts of the heterogenous whole that is the city, the respective goods of citizens and cities do not just differ numerically, but also in kind.^[24] For our purposes, what this clearly implies is that common goods (read: ends) are precisely those which individuate acts belonging properly to social groups. To say that social groups are capable of such acts just is to admit the aforementioned phenomena of “emergent powers” in social groups.

For Aquinas, then, it is quite clear that social groups such as political communities and armies have distinctive, emergent powers that correspond with formally distinct objects. To put the same point another way, there are acts whose subject must be a social group—if for no other reason than that an individual acting qua individual could not even perform the act or accomplish the end. No individual soldier—or commander, for that matter—can properly carry out assaults or achieve victory in war. If we do say that the commander does and achieves these things, it is because the commander acts as the “soul” (i.e., a governing part) of the army.^[25] Properly speaking, assaults and victories are things that armies do and achieve, respectively.

Aquinas’ view has interesting implications. For example, no individual—not even the statesperson or king qua individual—can properly perform acts of distributive justice (S.th., 2-2.61.1c) or achieve “peace and concord” (De Reg., I.3), “communal happiness” (S.th., 1-2.90.2c), all of which are expressions of the bonum commune proper to the political community as such (S.th., 1-2.99.2c). It is a condition of possibility for these properly common goods that they be “secured” amongst citizens who correctly understand themselves as part of a whole that is formally distinct from themselves as individual persons. In short, these activities can only be carried out together, i.e., in a non-distributive sense.

In fact, according to Aquinas, if the common goods associated with these various social groups were mere aggregates of individual goods, then we would not be able to distinguish the so-called “natural societies” (e.g., political community, Church and family) except by virtue of the trivial fact that each tends to involve greater and lesser numbers of people standing in different, accidental relations to one another. Such a conclusion is taken by Aquinas to be absurd on its face, since the way in which, e.g., a father relates to his children is obviously qualitatively different from the way in which a king relates to his subjects.^[26] The obviously correct view, says Aquinas, is that these two social relations differ according to species, from which it is inferable that the two social groups each have common goods that are formally irreducible to the individual goods of their members. It is a different thing to intend and act as a father than to do so as king, and this is because fathers and kings intend and act as parts of different social wholes.

Finally, it is worth noting that Aquinas sometimes distinguishes between “intrinsic” and “extrinsic” common goods. In his commentary on Book Λ of Aristotle’s Metaphysics, he remarks, “[A]n end is extrinsic to that which is ordered to it, as when we say that a place is the end of something that is moved to a place. And also it is intrinsic, as a form is the end of the process of generation or alteration; and [this] form already acquired is a kind of intrinsic good of the thing whose form it is” (In Met., XII.12.1). This distinction applies directly to the case of social groups, and again Aquinas is fond of the example of armies: “for the good of the army is found both in the order itself of the army and in the commander who is in charge of the army … namely, his will to attain victory” (In Met., XII.12.4).^[27]

Thus the intrinsic common good of an army (its unique composition of structural features, e.g., ranks, branches, and other roles/functions) functions as a quasi-formal cause^[28] in the sense that it accounts for the army’s distinctive arrangement of parts; and, correlatively, the army’s extrinsic common good (the establishment of victory conditions in war) functions as a quasi-final cause. Political communities also have intrinsic and extrinsic common goods, according to Aquinas, since it is possible to distinguish among different kinds of (legitimate and illegitimate) regime-types (e.g., monarchy, aristocracy, democracy, etc.) that have peace and virtuous living as their ultimate aim (De Reg., I.15). To make such distinctions, however, is precisely to imply that there are intrinsic and extrinsic common goods (as discussed in Goyette 2013, p. 153). Without this fundamental principle—namely, that common goods differ from individual goods formally rather than numerically—these familiar categories of political science in Aquinas’ Aristotelian tradition would be ultimately unintelligible.

3.3 The Common Good and the Numerical Unity of Social Groups

There is a third and final core conviction shaping Aquinas’ account of social groups: namely, that (intrinsic and extrinsic) common goods are not merely qualitatively identical as intended by individual members, but also numerically identical. This conviction is important because it rules out the possibility that the Thomistic concept of common good is simply an end “common” to members of a social group in the way that, e.g., “health” is commonly desired by individual persons: namely, as the same “type” of end is instantiated by different “token” instances of individual desire (see Goyette 2013, p. 138).^[29] In fact, Aquinas’ position is that the common good proper to a given social group is numerically identical—even as it is desired and intended by different individual members. That is to say, the common good is not “instantiated” by the minds of individuals merely in the way that a universal concept is instantiated in particulars. On the contrary, the common good—intrinsic and extrinsic—is quite concrete (S.th., 1-2.90.2 ad 3). However one puts the matter, at least this much is clear: according to Aquinas, there is numerically one common good precisely to the extent that there is, numerically, one social group.^[30]

Earlier we took note of the apparent peculiarity of Aquinas’ distinction drawn in Summa theologiae 2-2.58.6c—that is, the distinction between two modes of generality: “by predication” and “according to power”. Justitia is a “general” virtue, says Aquinas, in that its object (bonum commune) is general in the latter sense. This may seem peculiar, since the more relevant point seems to be about the different modes of action (i.e., qua individual and qua part) that are enacted by members of social groups.

However, having come full circle on Aquinas’ notion of bonum commune, this peculiarity dissolves. As it happens, it is crucial for Aquinas to distinguish these two senses of generality precisely in order to avoid the “individualism” that results from a notion of common good that is merely notional, i.e., a “being of reason” (ens rationis) or “type” that happens to have “token” instances in the intentions of individual members of a community. Aquinas’ position is more strongly anti-individualist. Indeed, precisely because the common good is common secundum virtutem, there is a clear sense in which it is more than just one “object” of intention/desire among others. In fact, not coincidentally, to perform the operations proper to justitia generalis is to do so under the aspect of an entirely distinct mode of action.^[31] After all, it is a unique feature of general virtues that they order not only operations, but also other virtues: “[general] justice is said to be a general virtue, namely, insofar as it directs the acts of the other virtues to its own end. This is to move [movere] all other virtues by command [per imperium]” (S.th., 2-2.58.6c).^[32]

3.4 The Irreducibility Claim

Therefore, with respect to Schweikard and Schmid’s Irreducibility Claim, three salient points arise out of Aquinas’ remarks on the ontological and agential status of social groups. The first pertains to their mereology. As we have seen, Aquinas categorizes social groups such as political communities and families as heterogeneous rather than homogeneous wholes. Heterogeneous wholes have two distinctive properties: (1) that their proper parts are formally (as opposed to merely numerically) distinct from one another; and (2) that the form of the whole does not belong to the parts as such. Thus, for Aquinas, social groups are clearly “irreducible” to their members in the sense that they contain formally distinct parts whose intelligibility and existence depends on the form of the emergent whole of which they are parts.

Second, we have seen that Aquinas clearly holds that such social groups have emergent powers (e.g., a political community’s power to enact distributive justice). That is to say, there are some powers and acts for which only a social group can be the proper subject. To the extent that these powers and acts are verifiable, then, Aquinas clearly holds that the social groups that have them exist and act in the world, i.e., in a way that is not merely reducible to their members.

Finally, we have seen that Aquinas’ analysis depends importantly on his claim that the common good of a given social group is not only qualitatively but also numerically one. That is to say, far from being some intentional object that merely happens to be “shared” by its individual members, Aquinas holds that the common good functions as a principle of unity for the social group considered as an object of analysis in its own right.^[33] Again, the clear implication of Aquinas’ analysis is that social groups are irreducible—at least to the extent to which the common good (in its intrinsic and extrinsic dimensions) serves as a principle of numerical unity.