Introduction

In business ethics, Kant’s moral philosophy is often subsumed in the deontology category (Micewski and Troy 2007; Bowie 2017; Crane et al. 2019; Melé 2019). This means that Kant’s emphasis on rights and duties has been used to advocate for issues such as “meaningful work for employees, a democratic workplace, non-deceptive advertising, and a non-coercive relationship with suppliers” (Bowie 2002: 12), among many others. There is more skepticism in applying Kant’s philosophy to describe the morality of the market exchange between individuals (market transactions). This might be connected to the influence of the authors advocating the thesis of Moral Purism (Henceforth, MP), according to which Kant would have classified all the actions involving empirical motives as immoral. The main claim of MP, in the name of Kant or under his aegis, is that markets are morally negative because there is self-interest involved; as Kant would have argued, morality is crowded out by the presence of self-interest—the so-called exclusion (Dubbink and Liedekerke 2020: 380) or incompatibility (Baxley 2010: 31) thesis. More than an established set of theories, MP is an implicit consensus among many authors around the idea of ‘purity of intentions’ (Dubbink and Liedekerke 2020).

Much has been written to confute MP’s interpretation of Kant’s ideas as applied to business ethics (Herman 1993; Thiel 2013; Bowie 2017; Dubbink and Liedekerke 2020)Footnote 1. Less has been done to confute the implications of MP for the morality of market exchange between individuals. This is the gap in literature that my paper aims to fill. In doing so, however, I will not directly address MP. Conversely, I will focus on a different branch of literature that, in my view, provides the philosophical foundation for any MP account.

I am referring to the scholars working on the moral limits of the market (MLM, henceforth) who employed Kant’s moral philosophy as one of the sources to ground their argumentation (Anderson 1993; Held 2002; Sandel 2009, 2012; Satz 2010; Bénabou et al. 2022; Dorfman and ‎ Harel 2021; Taylor 2022). These authors generally rely on two passages from one of Kant’s masterpieces in moral philosophy, Groundwork of the Metaphysics of Morals ([1785], 2012). On the one hand, there is the formula based on humanity, that is, “so act that you use humanity, in your own person as well as in the person of any other, always at the same time as an end, never merely as a means” (Kant 2012: 41). On the other hand, the idea of a kingdom of ends clearly states that “everything has either a price, or a dignity” (Kant 2012: 46). Both passages seem to build a wall between markets and morality, relegating the former to the sphere of amorality or immorality.Footnote 2.

I immediately need to reveal my own understanding of the aims of this branch of literature. I find that MLM’s arguments aim to classify the whole market sphere as immoral or amoral. The periphery is attacked, but the real target is the center (market transactions between individuals included). As I will try to prove in “Kant Between Immoral and Amoral Markets” section, the shared assumption is that there is something morally base or neutral in the economic theory of agency that should be circumscribed to preserve the morality and goodness of other spheres of social life. Blending Anderson’s (1993) lexicon, this assumption could be expressed in this double way: values in economics bring down values in ethics (immoral), or values in economics are totally other than values in ethics (amoral)Footnote 3. While MLM’s literature mainly relies on other philosophical traditions (virtue ethics), Kant’s Groundwork is often mentioned and used as further proof of their arguments. The peripherical role of Kant’s argumentation in MLM would not be a problem per se. Still, it becomes such because it is associated with a misunderstanding of Kant’s own ideas.

I aim to show that Kant’s moral philosophy, as exposed in the Groundwork, has been too simplistically interpreted as hostile to the markets. Against MLM literature, I will argue that Kant did not see market exchanges between individuals as necessarily immoral or amoral. My analysis will show that a correct understanding of Kant’s philosophy provides a model that can be employed to make moral judgments regarding everyday market transactions. This model is grounded on the universalization of what I call the maxim of mutual assistance (MMA) and the resulting duty of honoring the spirit of mutually beneficial contracts. I will make the reader familiar with those concepts throughout the manuscript. For now, a parallel with medicine can be useful: to detect the ills of the human body, we need an understanding of the human being in perfect health. The same is true for the market. To judge empirical market transactions, we need to move to the principle of morality, i.e., the realm of the metaphysics of morals. From Kant’s moral philosophy, I will therefore infer a picture of what a morally good market transaction looks like; the colors of this picture will be the maxims, i.e., the subjective principles of action and the duty of the economic agents involved. In my reading, Kant implicitly provided us with a description of how the motivations of agents engaged in an economic transaction should look to be moral, or, in other words, what the market in the kingdom of ends would look likeFootnote 4. I will also show that in the Kantian framework, the encounter between moral and economic values, rather than undermining or excluding the former, dignifies the latter.

To prove my point, I have structured the paper as follows. In the second section, I will examine how Kant’s moral philosophy has been discussed in the MLM literature, analyzing different interpretations and stressing problematic issues. This will set the stage for my reading of Kant’s moral philosophy applied to market transactions. Its main elements, i.e., the notions of the market in the kingdom of ends, the maxim of mutual assistance, and the duty of honoring the spirit of mutually beneficial contracts, will all be presented in the third section. The fourth section will consider some objections to my own interpretation. For each of them, I will provide a rebuttal. Final remarks for future developments will end the paper.

Kant Between Immoral and Amoral Markets

In the MLM literature, Kant’s moral philosophy, as expressed in the Groundwork, is employed to argue for two different theses: (1) markets are immoral or (2) markets are amoral. My own reading of Kant’s view as applied to the market differs from these two positions. However, discussing them is relevant to setting the stage for my own argument.

Anderson mentioned Kant to qualify her distinction between intrinsic and extrinsic goods. All human beings act to pursue some ends: if an end is valued as good in itself we are in the presence of an intrinsic good; if we value an end as good just because it is connected to another good end, that is an extrinsic good.Footnote 5 Where is Kant situated in this distinction?

Kant’s famous imperative to regard humanity as an end in itself expresses something similar to the first sense of “end” I have in mind when I say that intrinsic goods are the ends for the sake of which we act. Taking humanity as one’s end is to act for the sake of or with due regard for the persons affected by one’s actions. Such action involves not only promoting their welfare but can also include such activities as participating in projects important to them or taking their opinions seriously in discussion (Anderson 1993: 19–20).

The importance of this passage is revealed in Chap. 7, where Anderson deals with “The Ethical Limitations of the Market.” Kant is never explicitly mentioned. However, the lexicon employed leaves little room for doubt about Kant’s presence: “[W]e understand the nature of economic goods by investigating the ways we value commodities.… I call the mode of valuation appropriate to pure commodities “use.” Use is a lower, impersonal, and exclusive mode of valuation. It is contrasted with higher modes of valuation, such as respect” (Anderson 1993: 144; my emphasis). Something similar was argued by Sandel: “On the Kantian liberal view there are two modes of valuation: respect for human beings, for human dignity, and for everything else use” (Sandel 2011: 140).

As explained by Von Hagen (2014: 21), “without proper acknowledgment to Kant, Michael J. Sandel warns that by attaching monetary prices to things, society reduces them to commodities and that this may deny them their proper valuation with dignity and respect. As Sandel puts it: “sometimes, market values crowd out nonmarket values worth caring about”” In Chap. 1 of her book, Anderson describes how we value goods differently and how different goods elicit different evaluative responses from us. The quote on price-dignity from Kant’s Groundwork is mentioned to distinguish goods with relative worth from goods with intrinsic worth. Evaluations are revealed in actions: people evaluate goods of relative worth by using them and the goods of intrinsic worth by respecting them. Anderson then comments, “Kant’s ideal of human rationality grounded his distinction between the way we should value persons and the way we should value things” (Anderson 1993: 9).

In my reading, the message of MLM is twofold. The first part concerns the moral limits of the market. Some goods should not be considered ‘economic goods’ because economic logic is not the correct evaluative mode to address them. Held thinks this applies only to extreme and non-controversial cases, like slavery: “Kant’s principles provide the strong and important constraints of having to treat people fairly and to respect their rights. They would rule out slave markets. But we don’t get from Kant or his followers, 1think, sufficient grounds for deciding, within the constraints of rights, how wide or how narrow the reach of the market should be” (Held 2002: 29).

Anderson and Satz disagreed with Held, believing that Kant’s argument is useful for understanding where to put limits in the market. Health, friendship, human beings, freedom, rights, animal rights, and many other thingsFootnote 6 should not be for sale. When passing through the market, these goods are undermined—this is the meaning of ‘lower’ in aforementioned Anderson’s quote—by an incorrect mode of evaluation. Therefore, economic logic must not invade spheres of social life: it must be confined to the exchange of commodities so that we can be sure that noneconomic goods remain so and that they will not be commodified. A similar argument is advanced by Satz (2010), who explicitly mentions Kant:

[I]n the nature of our concepts of honor, divine grace, and true love … these things have no market price. At the very least, using the market to distribute these goods would represent a change in the way people understand these goods; our current usages would be undermined. Someone who offers to buy my friendship does not really understand what it means (in our culture) to be or to have a friend. There are also some goods that people regard as simply irreplaceable, without any equivalent. As Kant said about human beings, they have a dignity and not a price. (Satz 2010: 80; my emphasis).

I have nothing to add or change about this thesis. I share Anderson’s and Satz’s worries about the commodification of certain ‘irreplaceable’ goods, and I think that the appeal to Kant’s concepts is rightly placed.

My concern begins with the second message advanced by Anderson in Chap. 7 and, in general, underlying many positions in MLM’s literature. Here, I think Anderson (as Satz) seems to imply that the market is an immoral zone. As rightly noted by Bruni and Sugden (2013: 146), “Anderson is presenting market norms as a kind of second-rate morality: the market’s mode of valuation is lower than of other domains of social life.” Economic goods are related to the category of use, rendering the people dealing with them less ‘moral’ than people dealing with goods that should be treated with respect. In the market, only instrumental goods are exchanged. However, we must not forget that all instrumental goods are extrinsic goods; nothing intrinsic is present in the market. In turn, this means that in a market transaction in which I am dealing with other people, I do not have to act as if I am “participating in projects important to them” (Anderson 1993: 19–20). Anderson explained this feature of ‘impersonality’ through Kantian concepts: “[E]ach party to a market transaction views his relation to the other as merely a means to the satisfaction of ends” (Anderson 1993: 145)Footnote 7. Blinded and driven by my wants, I egoistically use the other party in the market exchange as a mere means of obtaining what I want.

Some possible objections can be advanced. On the one hand, they argue that Anderson does not define a market as an immoral zone. If anything, markets are amoral, meaning that morality is not the correct mode of evaluation for economic logic. In this reading, markets can be equated with competitive sports; even if we think there is nothing morally good in competition, this does not imply that there is something morally base. If something, it is the category of morality that is external to economic domains. On the other hand, I would have misinterpreted the MLM literature’s main message, as Satz and Anderson represented it. The core of that thesis is that the expansion of markets and their logic of evaluation crowds out other evaluation logics, thus diminishing/undermining human autonomy.

An initial reply to both valid points would be that I am not interested in MLM arguments as such but in their specific usage of Kant’s ideas to sustain parts of those arguments. Nevertheless, both objections are valid and worth discussing. The difference between amoral and immoral lies in how we interpret Anderson’s adjective ‘lower’ and the verb ‘undermined’ employed by Satz. Both terms make me think that there is a standard of morality from which the market is more distant than other domains of social life. Does this make the market morally base? Maybe this is not true in absolute terms (markets are ‘evils’). Still, it holds in comparative terms, similar to saying that the morality of the market is lower than that of other spheres of social life. Even if the core of the MLM authors is that markets are amoral, their usage of Kant’s view seems closer to an immoral (perhaps low-moral) view. In this framework, the range of moral motivations of individuals involved in a market exchange reduces so much that quasi disappeared.

As I specified in the Introduction, I want to object to the MLM authors’ idea of considering market transactions as a morally base or free zone, especially because this understanding comes from a problematic interpretation of Kant’s ideas. When they recall Kant’s idea of the kingdom of ends, MLM authors misuse it. In the introduction to the Groundwork, Kant makes it clear that he is dealing not with the empirical but with the rational part of the discipline, more specifically that the “pure part of philosophy … limited to determinate objects of understanding” (Kant 2012: 4). When applied to ethics, this would be the metaphysics of morals (metaphysik der sitten). The scheme he presents is as follows:

$$\mathbf{Ethics}\ (Ethik)=\mathbf{Moral \ Science}\ (Moral)+\mathbf{Practical \ Anthropology} \ (praktische \ Anthropologie)$$

Therefore, the kingdom of ends pertains to Moral Science, while the MLM’s literature uses it as if it is immediately related to ethics. This is the same mistake made by MP’s authors: take concepts from the Metaphysics of Morals and apply them to empirical reality. Kant’s moral philosophy is more articulated, as I will show in the next section.

The Market in the Kingdom of Ends

Kant’s Groundwork is a book with a precise aim, as declared by the author in the preface: “the present groundwork, however, is nothing more than the identification and corroboration of the supreme principle of morality” (Kant 2012: 7). The German Grundlegung, in fact, means precisely “laying the ground.”Footnote 8 After inquiring about how we know objects, Kant turns his attention to how we ‘produce’ objects- how we bring objects to life (pro-ducere) through our actions. We always act according to certain principles. There is a need to find morality’s basic and supreme principle to clarify moral science. Kant’s aim in this book is both descriptive (“to identify” Kant 2012: 7) and prescriptive (“to corroborate” Kant 2012: 7). Where can we find the supreme principle of morality? Experience cannot reveal such to us, since it is concerned just with the world as it is, whereas morality is concerned with the world as it should be. As is well-summarized by Korsgaard, “[I]f there are any moral requirements, then there must be a metaphysics of morals, a body of synthetic a priori judgments concerning what we ought to do” (2012: XII; see also Korsgaard 1996). As Kant realized in his Critique of Pure Reason, the foundational attempt can succeed in the a priori/pure realm.Footnote 9

Morality concerns what we ought to do rather than what we want to do; it is about duty. Duty “is the necessity of an action from respect for the law” (Kant 2012: 16). We perceive moral law as a categorical imperative because it is binding to us, often contrasting with our natural inclinations. For Kant, if someone is born inclined to help others, promote their welfare, and participate in their projects, this tells us little about their moral worth. Morality is about duty, not about natural inclination (it might be argued that an indifferent human being who helps other people out of duty is more moral than the good Samaritan of the parable).

To better explain his view, Kant introduces the concept of the kingdom of ends. If a human being abstracts from any material ends she wants to pursue, if she remove every empirical determination and think of herself as rational, and therefore free and autonomous, and if she conceives herself in relation to other rational beings all ruled by self-imposed rules, then she has walked through the door of the kingdom of ends. This realm is not to be thought of as really existing somewhere; it is an ideal to which all human beings can have access insofar as they are rational beings.

What would be the moral laws established in the kingdom of ends? Is the market included in the kingdom of ends? If so, which view of the market? Recall that Anderson describes the market as the realm of ‘use’, which is impersonal, egoistic, exclusive, want-regarding, and oriented to ‘exit’. Can ‘use’ be the moral law of the market of the kingdom of ends? Kant denied this possibility. In Groundwork, he provides us with an argumentation for sustaining this position. His discussion of the first formula of the categorical imperative, from which moral laws should be derived, is very telling. The first formula goes as follows: “act only according to that maxim through which you can at the same time will that it become a universal law” (Kant 2012: 34). Libraries have been filled with books trying to understand what this ‘universalization’ or ‘generalization’ means (O’Neil 1975; Korsgaard 1985; Singer 1985; Rawls 2000; Sensen 2014; Kleingeld 2017). A maxim is the subjective principle of an action. For my purposes, it is enough to be faithful to the intended meaning of the Kantian text and to the example he provides for explaining it to the reader:

Yet a fourth, who is prospering while he sees that others have to struggle with great hardships (whom he could just as well help), thinks: what’s it to me? May everyone be as happy as heaven wills, or as he can make himself, I shall take nothing away from him, not even envy him; I just do not feel like contributing anything to his well-being, or his assistance in need. (Kant 2012: 36)

Recall Anderson’s usage of ‘impersonality’ as a feature characterizing the market exchanges between individuals: before and during the market exchange, I am not concerned with the well-being of the parties I am trading with. I might be interested in their projects, but only insofar as those projects are helpful for the realization of mine. To ‘universalize’ this maxim, we need to imagine a society where every rational being in the same situation follows the maxim as the principle of their conduct. Kant does not refer specifically to the market sphere, yet his argumentation can be applied to it in the way Anderson applies it.

According to Kant, the right question to ask is twofold: Can we conceive of this society? Can we will such a society? “Now, certainly, if such a way of thinking were to become a universal law of nature, the human race could very well subsist, and no doubt still better than when everyone chatters about compassion and benevolence … but also cheats whenever he can, sells out the right of human beings, or infringes it in some other way” (Kant 2012: 36). In the technical terms employed by Kant and Kantian scholars, there is no contradiction in conception. A society or kingdom where everyone cares about their business can still endure. But can we will it? “[E]ven though it is possible that a universal law of nature could very well subsist according to that maxim, it is still impossible to will that such a principle hold everywhere as a law of nature.…] One must be able to will that a maxim of our action become a universal law: this is as such the canon of judging morality” (Kant 2012: 36). If there is a contradiction in will, morality is absent. As rational beings, we cannot will the market in the kingdom of ends grounded on the moral law derived from the maxim of ‘use.’ So far, MLM’s literature seems to have provided a fair interpretation of Kant’s moral philosophy.

Therefore, we need to look for an alternative view of the market. If ‘use’ does not work, we might be tempted to depict a market grounded in ‘respect’. Yet, we are prevented from entering this path by Kant himself. In describing the kingdom of ends, he introduces the dichotomy between price and dignity. Anderson recalls this to mark the difference between economic and moral evaluations. In Kant’s own words, “What is related to general human inclinations and needs has a market price … that which constitutes the condition under which alone something can be an end in itself has not merely a relative worth, that is, a price, but an inner worth, that is, dignity” (Kant 2012: 46). Morality concerns dignity, not price; respect, not use. Again, MLM’s literature was right in using Kant’s philosophy as a way to characterize market exchanges as immoral or amoral.

The contribution of my research is to show that Kant escaped from this dichotomy. There is a third way between ‘use’ and ‘respect’ that creates a bridge between these two modes of evaluation. If this were just my claim, then it would have little value in addressing the MLM interpretation of Kant. However, Kant opened up this possibility, and he did so in his lectures on Natural Right (1784), namely, the lessons that he gave to students of Königsberg University while writing and publishing Groundwork. What is Kant’s third mode of evaluation?

From the point of view of reason, things in nature can only be regarded as means to ends, but man alone can himself be regarded as an end. It is impossible to conceive of a value of other things other than by regarding them as means to further ends…. However, man is never merely a means; rather he is at the same time an end. For example, if a mason serves me as a means to building a house, I serve him, in turn, as a means to acquire money. (Kant [1784] 2016: 81)

To prove his point, the lecturer Kant provided his student with an example:

My freedom agrees with that of another if he agrees with it. If I arrange with my servant to give him 20 reichsthalers per year but it later turns out to be more expensive to live so that he cannot make do with that money I do him no wrong if I continue to give him no more than 20 reichsthalers even though he asks for more, for I act in accordance with his [earlier] expressed attitudes. I have nonetheless not act[ed] equitably because he had thought that he would be satisfied with the 20 reichsthalers only as long as the relatively inexpensive times would allow it. I would be able to assume his intention […] ‘Equitable’ can also be called ‘ethically just’.” (Kant [1784] 2016: 92–93).

Kant is arguing that is a third mode between use and respect: ‘to serve,’ ‘to assist’: “For example, if a mason serves me as a means to building a house, I serve him, in turn, as a means to acquire money” ((Kant [1784] 2016). In Kant’s view, when ‘assistance’ becomes reciprocal—that is, when I am serving you in achieving your ends and vice versa, while we both promote our own ends (otherwise it would have been reciprocal altruism)—then, we have a transversal union between price and dignity. In market exchange, goods (things) are conceived in relation to people. The economic actors both want to realize their ends; it is how they do so that is decisive for understanding where there is room for the market in the kingdom of ends. Kant is very explicit in opening the door of the kingdom of ends to the market transaction.

What would be the moral law of the market in the kingdom of ends? Going over the letter but remaining faithful to the spirit of Kant’s philosophy, I propose the maxim of mutual assistance (MMA, henceforth):

Maxim of mutual assistance: During a market transaction, within the realm of a mutually beneficial contract, I will promote my aims and, at the same time, the aims of the person with whom I am trading.Footnote 10

We should now ask ourselves if this maxim would be feasible within a free market economy and what kind of duty it would entail. The ‘during’ at the beginning means that I am free to choose the party with whom I will exchange goods and sign a mutually beneficial contract and that during the market transaction, I can still promote my own aims. Therefore, economic freedom is preserved. We must then understand if this maxim will pass the ‘contradiction in conception’ and ‘contradiction in will’ tests to become a universal law. To formulate the question, is it possible to imagine a market exchange in which the parties renounce impersonality and egoism in favor of cooperation toward a mutual benefit? If so, is such an exchange desirable? Both questions can be answered by recalling the second formulation of the categorical imperative, known as the formula of humanity: “so act that you use humanity, in your own person as well as in the person of any other, always at the same time as an end, never merely as a means” (Kant 2012: 41).

As Kantian scholars for centuries, the attentive reader has noticed that in the formula about humanity, Kant adds ‘merely’ (bloß) as a means. In Kantian terminology, the means is the ground of the possibility of an action, the effect of which is an end. In contrast, the end is the ground of an action’s possibility. If you use others as mere means, just as a tool for your own purposes, then you are outside the sphere of morality. The implication is that there is a way for other people to be ‘means’ to our ends that does not reduce them to mere tools. This Kantian openness is of the utmost importance because it refuses the binary logic (means = immoral and ends = moral) that is sometimes applied to it. Even from the point of view of the first categorical imperative formula, no contradiction in conception can arise: we can imagine a market sphere in which we have promoted others’ ends alongside our own. Different market transactions will require different levels of effort to help others promote their ends, especially when we also have to consider the promotion of our own ends. What about the contradiction in will? In this respect, Kant’s text leaves little room for doubt:

Humanity could indeed subsist if no one contributed anything to the happiness of others while not intentionally detracting anything from it; but this is still only a negative and not positive agreement with humanity, as an end in itself, if everyone does not also try, as far as he can, to advance the ends of others. For if that representation is to have its full effect in me, the ends of a subject that is an end in itself must, as much as possible, also be my ends. (Kant 2012: 42–43)

What kind of duty would emerge from the MMA? It is important to stress this point to disentangle the MMA from the wider range of the imperfect duty toward others. We owe the latter to everyone, the former to the person with whom we are involved in a market transaction. Kant implies that when we enter into contracts, we acquire a duty not only to honor the explicit terms of the contract but also to honor the mutually beneficial spirit in which the contract was made and the intentions behind the agreement. In the servant’s case, there is a duty to give the servant more because he agreed to work in exchange for enough money to live on, and he thought the amount they agreed to would be enough. So if Kant gives him 20 Reichsthalers, he is honoring the explicit agreement but not the mutually beneficial intentions/ spirit behind the agreement. My interpretation could explain why we owe something more to the servant than just the general imperfect duty of assistance we owe to all. The duty here is not one of assistance but honoring agreements.

It is crucial to clarify the meaning of ‘aims’ in the MMA. What counts as an ‘aim’ in a market transaction within the realm of a mutually beneficial contract? This clarification is of the utmost importance to better understand if we can move from the MMA to the duty of honoring the spirit of mutually beneficial contracts. Two kinds of aims can be distinguished: the aims a party signing a contract set for herself or the aims she effectively realizes thanks to that market transaction. In the case of Kant and his mason, the latter aimed to get money proportionate to the work performed. Due to inflation, the mason’s aim while signing the contract diverges from what he is actually able to achieve. Inflation is not Kant’s responsibility, it is simply a change in circumstances. And yet, Kant stated that it would be moral for him to promote the mason’s aim by raising his salary. Be careful here: Kant is not saying that any transaction in which the parties do not promote their respective aims in their effective realization is immoral. He simply states that, for the time span covered by the contract, morality requires an imperfect duty from the parties involved in a market exchange to consider the realization of their respective aims. Among the many meanings Kant gave to ‘imperfect duty’, there is the idea that these are duties of wide obligation. This means that there are cases in which a party can do more and cases in which the party will do less without infringing what duty requires. Additionally, there might be a conflict of duty. Suppose that after Kant increased mason’s salary, inflation continues to the point where the full professor Kant feels its effect. Should Kant raise his mason’s salary again? Should he prioritize the duty of honoring the spirit of mutually beneficial contracts over the duty he owes to himself? For these cases of conflicts of duties, there is no unique answer. Maybe new mutually beneficial contracts can be in place to cover these situations. Maybe circumstances will change again. Be as it may, we are moving from Morality to Ethics, and we can only express a full moral judgment considering the circumstances. What remains immutable, as always happens in the a priori realm of the metaphysics of morals, is our imperfect duty of honoring the spirit of mutually beneficial contracts.

Reciprocity is the key feature of the market in the kingdom of ends. I promote both my and your ends. The degree to which this can happen might vary from case to case, but if a market transaction does not advance my ends as well as yours as expressed in the contract, that would not be moral. Moreover, reciprocity entails a certain degree of equality—the same equality between rational beings in the kingdom of ends. MMA considers what happens during a market transaction, not before. Self-interest and even profit are good ethical motives for starting a business. Also, the ends that the other party wants to promote must be scrutinized before we sign a contract with the same party. The duty of honoring the mutually beneficial spirit of contracts explicitly assesses the morality of people’s behavior during the market exchange. It might be argued that starting positions, institutions, culture, and many other background elements should be considered when describing a market exchange. It might also be argued that the MMA and the subsequent duty do not consider positive and negative externalities. However, these are not a denial, but rather an enlargement, of the market in the kingdom of ends, and they would require a separate analysis.

All these things considered, the market in the kingdom of ends can be grounded on the moral law resulting from the universalization of the MMA, and it generates a duty of honoring the spirit of mutually beneficial contracts.

Objections and Counterarguments

Effects, Ends, Ought

I will now address some objections to clarify and refine the idea of the market in the kingdom of ends based on the MMA.

First, it could be argued that I am overlapping the empirical and rational realms. After all, Groundwork is a search for the supreme principle of morality in the pure and a priori realms. In contrast, market transactions are ruled by the very empirical principle of self-interest, a feature of the a posteriori/empirical realm. Even when our self-interested actions are mitigated by a sincere concern for others, as provided in the MMA and the subsequent duty, we are still in the empirical sphere. Morality, for Kant, is a different animal:

It is clear from what has been said that all moral concepts have their seat and origin completely a priori in reason … that they cannot be abstracted from any empirical and hence merely contingent cognition … that every time in adding anything empirical to them one takes away as much from their genuine influence and from the unlimited worth of actions. (Kant 2012: 25–26)

This objection can be divided into two sub-objections. On one side of the coin, Kant’s moral philosophy is built upon the idea that intended and actual effects say nothing about the morality of an action. What I want to realize effectively is not the locus where we should look for morality. This reference to intended effects seems to undermine my attempt to prove that it can be moral for the parties of a market exchange to try to realize their own aims alongside the aims of others. The other side of the coin is that Kant is very specific in saying that the categorical imperative deals with general and valid ends for all rational beings. Those need to be distinguished from relative ends: “the ends that a rational being intends at its discretion as effects of its actions (material ends) are one and all relative … all these relative ends are the ground of hypothetical imperatives only” (Kant 2012, 40).Footnote 11 Here, a problem emerges: by relating the categorical imperative and the kingdom of ends to market transactions, I am applying something that pertains to objective ends (morality) to something grounded in subjective ends (the market).

The first sub-objection could be addressed by recalling Kant’s distinction between the world of the senses and the world of understanding, as explored in Section III of Groundwork. A rational being, one that counts itself as belonging to the world of understanding, can never think of the causality of his own will, that is, its causality from this world, other than under the idea of freedom. This is because in thinking of himself as independent of the determining causes of the world of sense (desires, inclinations), he thinks of freedom and, subsequently, autonomy, the property of the will of being a law unto itself. If the rational being were a mere member of the world of understanding, however, a categorical imperative could not be considered, for all our actions would conform perfectly with the principle of morality. If we were mere members of the world of sense, they would conform to the natural law of desires and inclination.

From where, then, comes the moral ought? We intuit ourselves to be members of the world of understanding and sense since our will is affected by sensuous desires, and, at the same time, we conceive of ourselves as autonomous. The ought is thus the necessary willing as autonomy from the member of the world of understanding who sees himself at the same time as a member of the world of sense. What should we then make of this friction? Kant says that it must be presupposed that no true contradiction can be found between true freedom and natural necessity, for we cannot give up the concept of nature any more than that of freedom. When such a contradiction seems to appear, the fault lies precisely in that: appearances. We must consider the human being as a phenomenon to make the laws of nature hold with regard to human actions; however, when considering the causality of their will, one is considering them as a phenomenon too, although their membership in the world of understanding demands they be thought of as a noumenon. When one makes this mistake of thinking of them as a phenomenon in both cases, it triggers a contradiction between natural necessity and freedom. However, when thinking correctly, that is, of the causality of their will as a noumenon, one cannot demand that the laws of operation be the same as those under which the phenomenon stands; hence, the contradiction disappears.

What are the implications for the relationship between duty and self-interest? When I universalized the MMA, I created a principle that pertains to the world of understanding. It could be rightly argued that most people involved in a market transaction do not follow that principle; instead, they follow their self-interest, utility, preferences, etc. Market transactions take place in the world of sense. This impasse can be overcome as follows. The picture of the market transaction that results from the universalization of the MMA and the duty of honoring the spirit of mutually beneficial contracts is a model against which we can judge the empirical market transactions of everyday reality. The more significant the gap between the world of understanding and the world of sense, the more diminished the moral character of the market transaction. From this, it emerges that the ought is a way to get closer and closer to the model of the market in the kingdom of ends. With this argument, the first sub-objection is also answered: the model is about the kind of maxims adopted by the actors during the market exchange and the duties that emerge from them; therefore, the (intended and actual) consequences are not the loci of moral determination.

The second sub-objection can be summarized as follows: How can the members of the kingdom of ends advance their own ends if material ends are excluded? Kant makes a clarification that offers a way around this problem:

By a kingdom I understand a systematic union of various rational beings through common laws. Now since laws determine ends in terms of their universal validity, if we abstract from the personal differences of rational beings as well as from all the content of their private ends we shall be able to think of a whole of all ends in systematic connection (a whole both of rational beings as ends in themselves and of the ends of his own that each may set himself), that is, a kingdom of ends, which is possible in accordance with the above principles. (Kant 2012: 45: my emphasis)

The crucial distinction is between the empirically determined private ends and the ends of his own that each may set himself. The latter are rational ends that every kingdom of ends member wants to advance. This is also the advantage of employing the concept of the kingdom of ends for describing the market. Some readers might have wondered why the MMA and the two categorical imperative formulas were insufficient to sustain my argumentation. The reason is precisely because the legislative nature of the kingdom of ends, where every rational being is both a member and legislator, seems to imply a concern for and promotion of the rational ends of others. In this regard, Thomas Hill writes:

A third (and perhaps derivative) implication of the idea that members regard each other as ends in themselves is that they have a prima facie concern to see each person’s ends realized, or at least to ensure each person freedom to pursue his ends. Persons necessarily have ends, and one way of showing our special respect for persons is to favour rules which enhance their opportunity to satisfy their ends. (Hill 1992: 61–62)

What Hill defines as ‘special respect’ is what I translated as ‘mutual assistance.’ Hence, in the kingdom of ends, there is space for pursuing ends that are simultaneously personal (not private) and common to other members. This is all needed to open the door to the market sphere, the one based on the MMA and the duty of honoring the spirit of mutually beneficial contracts.

It might be argued that what I call MMA and the subsequent duty are closer to the category of respect rather than use. Korsgaard writes: “Respect for humanity, Kant believes, demands that we avoid all use of force, coercion, and deception, that is, all devices intended to override or redirect the autonomous choices of others. At the same time, it demands that we help to promote the ends of others, other things being equal, when they need our help” (Korsgaard 2004: 81). My own reading is that MMA is more than a different way of expressing respect. It is a bridge between two separate realms. The reciprocity in promoting respective ends is precisely the encounter between use and respect, their only possible way of communication that overcome their natural opposition. The duty of honoring the spirit of a mutually beneficial contract is the expression of this communication between use and respect.

The Kingdom of Ends and the Community of Advantage

The distinction between the rational and empirical realms for the maxim of mutual assistance and the subsequent duty is also important to mark the difference between my analysis and Sugden’s interpretation of Kant. After decades of research between behavioral economics and the philosophy of economics, Sugden summarized his work’s results in a book called The Community of Advantage (2003). In the last chapter of his book, and in the last section that resembles the title of the book, Sugden (2018: 278) recalls Kant’s passages from the lectures Natural Rights ([1784] 2016) to stress that “Kant offers an account of moral duty in a market relationship.” Rather than self-interest or altruism, the market is a cooperative venture for mutual benefit. Intended mutual benefits drive the parties involved in the market exchange. Sugden calls this view ‘mutual assistance’ (Bruni and Sugden 2008; Nalli 2021). This is Sugden’s take on Kant’s view of the market.

Sugden believed that the passages I mentioned in the third section from Kant’s Lectures proved his point. Kant’s relationship with his mason is not of simple use and abuse. One might argue that the stress of promoting others’ ends can cause a person to sacrifice their own. For example, if the mason building Kant’s house accepted a meager salary, he was still promoting Kant’s ends while undermining his own. In a different scenario, if Kant chose a low-qualified and dishonest mason because he was his old, good friend, he would prioritize the ends of the other over his own. We can imagine thousands of real-case scenarios that resemble these two, where personal aims are sacrificed for others’ aims. However, for Sugden this is not what Kant argued. In a mutually beneficial market transaction, both parties can be means and ends simultaneously. Contrary to what MLM argued, Kant’s moral philosophy does not crowd out intrinsic values from the market, neither does it undermine agents’ autonomy. In Sugden’s reading, Kant had empirically observed in his days that market transactions work like that.

In a later article, Sugden (2019: 14) returns to Kant’s view and adds, “for my present purposes, I am not concerned with Kant’s rationalistic metaphysics.” However, I am, as I think rationalistic metaphysics can yield a fuller picture of what Kant means and why it can be useful to understand the moral nature of markets.

Sugden’s view and interpretation are built on empirical grounds. Nothing could be more distant from Kant’s view:

Teleology considers nature as a kingdom of ends, moral science a possible kingdom of ends as a kingdom of nature. There the kingdom of ends is a theoretical idea for explaining what exists. Here it is a practical idea for the sake of bringing about – in conformity with precisely this idea – what does not exist but can become actual by means of our behavior. (Kant, 2012: 48)

Sugden employs Kant as if Kant were conflating the rational and empirical spheres. Sugden thinks that Kant’s view of the market in the kingdom of ends describes the normal (empirical) functioning of the market transaction. However, this is not what Kant had in mind, as the kingdom of ends is a concept employed in the pure part of Ethics, i.e., the Metaphysics of Morals. As I have argued, the specificity of Kant’s view of the market emerges only in the kingdom of ends conceived as a pure idea of reason. The empirical realm should be transformed to approximate this ideal, which, in any case, cannot be fully realized.

My interpretation of Kant’s view of the market provides a different argument from Sugden’s to address the MLM literature. Sugden is interested in the idea that markets are actually moral. He is concerned with real markets and real people. The market is a cooperative venture for mutual advantage rather than the realm of egoism. Sugden argues in favor of this view, bringing in elements from psychology, behavioral sciences, philosophy, etc. His usage of Kant follows this pattern. However, although meritorious, I see a problem connected to this line of argumentation, which a preposterous hypothesis can illustrate. Let us suppose that research in behavioral sciences proves incontrovertibly that all human beings are egoistic, driven by an egoistic ‘force’ that is predominant over others. Then, Sugden’s empirical defense of the moral nature of market transactions would fall since it would have been built on unrealistic presuppositions. Even virtue ethics and teleological accounts would not survive since the telos of the markets would be to realize their own potentialities fully, and those would be reduced to egoistic behaviors.

Kant’s view of the market in the kingdom of ends avoids this problem. One of Kant’s more recurrent arguments is that moral law’s validity is not tied to its recurrence in human behavior. Even if no one has ever seen a behavior driven exclusively by the categorical imperative, and even if no one can provide empirical proof of the reality of the categorical imperative, this does not undermine its validity. To make this concept clear, Kant advances an analogy with friendship: “and that, for example, pure sincerity in friendship can be no less required of everyone even if up to now there may never have been a sincere friend, because this duty - as duty in general - lies, prior to all experience, in the idea of a reason determining the will by means of a priori grounds” (Kant 2012: 22–23). Applied to the preposterous hypothesis, even if we have not had the experience of the market in the kingdom of ends in empirical life, this does not undermine that view on the moral nature of the market.

On the contrary, the distance of reality from the model would make the model clearer. To address the MLM authors’ view, Kant would have argued that even if some empirical realizations of markets are immoral, this does not mean that the market and morality are on opposite sides. To address Sugden’s view, Kant would have recognized its value as an example, as an empirical representation of how the maxim of mutual assistance grounds the market in the kingdom of ends. However, the foundation lies elsewhere: in the a priori realm. The novelty of my reading of Kant lies precisely in this basic understanding.

Conclusion

This paper aimed to show what model of the market exchanges between individuals can be inferred from Kant’s Groundwork. I do not think that Kant himself believed the market to be morally base or an amoral zone. He proposed his own version of market transactions, which I made explicit through the universalization of the MMA, the duty of honoring the spirit of mutually beneficial contracts, and, more in general, the concept of the market in the kingdom of ends.

The MLM literature and its interpretation of Kant’s Groundwork were the main focus of my attention. To them, I replied by arguing that Kant does not see markets as amoral, immoral, or undermining autonomy when the market is ruled by the universalization of the MMA and the duty of honoring the spirit of mutually beneficial contracts. In this respect, economic values do not bring down or crowd out moral values. Conversely, economic values are raised to the level of the moral sphere. However, I argue that Kant was not trying to produce an idealized model of that market since no empirical principle can pretend to be the role of the supreme principle of morality. Even if Groundwork contains implicit and explicit references to Adam Smith (division of labor, rational impartial spectator)Footnote 12, it was far from Kant’s intention to individuate the ‘pure’ grounds on which the empirical political economy was being born. Kant built his own ‘pure’ view of the market, ruled by a different maxim that, universalized, creates a new duty and the market in the kingdom of ends.

To conclude, I want to specify that the market in the kingdom of ends is not a model to be realized in full. As in Kant’s philosophy, perfectionism is not the inspiration for this paper. Perhaps I incur in the critique of Sen the charge of transcendental idealism, focusing too much on the ‘just society’ rather than solving manifest injustices (Sen 2009). What I can say is that I think of the market in the kingdom of ends as a fruitful idea for making ethical judgments that are not too clear-cut, such as those expressed in the dichotomies extrinsic–intrinsic, economic–moral, and self-interest–duty. Also, while the kingdom of ends might not be fully realized, it is still in our nature as rational beings to approximate the kingdom of nature to it as much as possible. Therefore, I think transcendental philosophy cannot be dismissed so easily, as it plays an important part in addressing manifested injustices. Like Kant, I think moral ideas should address the empirical real-world—morality has to become ethics. And yet, I can see the value of a moral Polar Star, which, in this case, coincides with Kant’s view of the market in the kingdom of ends.