What We Owe to Each Other

1. Introduction

What We Owe to Each Other is Thomas M. Scanlon’s major statement of a contractualist moral theory. The book aims to explain what makes actions right or wrong by appealing to principles that people could not reasonably reject when they regard one another as free and equal agents. Its title marks a focus on one central part of morality: the domain of duties we have to other persons, rather than to ourselves, to animals, or to impersonal values.

Scanlon develops three interconnected projects:

1. An account of reasons and value that does not reduce all reasons to desire or welfare.
2. A substantive ethical theory—contractualism—which holds that wrongness consists in acting on principles that others could reasonably reject.
3. An exploration of how this framework bears on responsibility, intention, personal relationships, and political institutions.

The book is written within the tradition of late 20th‑century analytic moral philosophy and engages directly with consequentialism (especially utilitarianism), Kantian ethics, and various forms of contractualism and contractarianism. It proposes that moral thinking is fundamentally a matter of justifiability to others: in deciding what we may permissibly do, we ask which principles governing our conduct could be justified to each person affected, considered as a separate center of agency.

Readers and commentators often treat What We Owe to Each Other as both a systematic overview of Scanlon’s earlier work on reasons and value and as a stand‑alone comprehensive moral theory. Subsequent debates tend to focus on how Scanlon understands reasonable rejection, how his view handles trade‑offs between persons, and whether grounding morality in interpersonal justification is philosophically and psychologically plausible.

This entry examines the book’s central ideas, situates them in their intellectual context, and surveys major lines of criticism and influence, while keeping a close focus on Scanlon’s own formulations and arguments.

2. Historical and Intellectual Context

What We Owe to Each Other emerges from, and intervenes in, several overlapping debates in 20th‑century moral philosophy. It is typically located in the post‑Rawlsian landscape, shaped by disputes between consequentialism, Kantian ethics, and contract‑based theories of morality.

Background Traditions

Late 20th‑Century Debates

The book responds to several ongoing discussions:

• Reasons and normativity: Against Humean and desire‑based theories of reasons, Scanlon sides with non‑psychologistic, object‑given accounts advanced by figures like Derek Parfit and contemporary neo‑Kantians.
• Critiques of maximizing ethics: Discussions by Bernard Williams, John Rawls, and others about integrity, separateness of persons, and anti‑aggregative intuitions set the stage for Scanlon’s rejection of simple welfare aggregation.
• Contractualism vs. contractarianism: Philosophers such as Gauthier developed contractarian views grounded in rational self‑interest, while Rawls and others framed contracts in terms of fairness or reasonableness. Scanlon positions his contractualism on the “moralized” side of this divide.

Academic and Cultural Context

The work is shaped by the Anglo‑American analytic style in the later 20th century: emphasis on argumentation, thought experiments, and reflective equilibrium. It appears at a time when moral and political philosophers were reconsidering foundations of liberalism, debating rights, equality, and the proper role of welfare economics in public policy.

Some commentators also note the broader cultural context of increasing attention to individual rights, anti‑paternalism, and skepticism about aggregative cost‑benefit reasoning, which made a person‑centered, non‑aggregative theory especially salient when the book was published in 1998.

3. Author and Composition

Thomas M. Scanlon (b. 1940) is an American moral and political philosopher associated with the Harvard philosophy department. Prior to What We Owe to Each Other, he had already become well known for influential articles on freedom of expression, contractualism, and the nature of value and reasons.

Intellectual Biography and Influences

Scanlon studied at Princeton and Harvard and was strongly influenced by John Rawls, to whom What We Owe to Each Other is dedicated. His early writings engage with:

• Liberal political theory, especially issues of rights and freedom of expression.
• Metaethics and value theory, including critiques of desire‑satisfaction accounts.
• Moral motivation, exploring how reasons can move us independently of self‑interest.

These themes are integrated and systematized in the book.

Composition and Development

The core ideas of Scanlonian contractualism were developed in a series of essays from the late 1970s onward, including “Contractualism and Utilitarianism” (1982) and “Values, Goals, and Reasons” (1982). Scholars generally view the book as the culmination of nearly two decades of work.

Contemporary accounts suggest that Scanlon wrote and revised the manuscript while actively testing arguments in seminars and conferences. The final structure of the book reflects both this long gestation period and continual interaction with colleagues, students, and critics within the Harvard environment and beyond.

The work is often read together with his later Moral Dimensions (2008), which further develops ideas about blame and permissibility; however, What We Owe to Each Other itself is generally treated as the definitive exposition of his contractualist theory of “what we owe to each other” understood as duties to other persons.

4. Structure and Organization of the Book

What We Owe to Each Other is organized into eight main chapters plus a brief introduction (within the book itself) and connecting sections. Each chapter contributes a distinct piece to Scanlon’s overall contractualist framework, while also being readable as a relatively self‑contained essay.

Chapter Layout and Internal Logic

Patterns of Argument

Scanlon’s organization follows a foundational‑to‑applied progression:

1. Chapters 1–3: Metanormative foundations about reasons, value, and motivation.
2. Chapters 4–5: Statement and elaboration of the contractualist criterion of wrongness, with attention to aggregation.
3. Chapters 6–8: Applications and clarifications in relation to responsibility, personal relationships, and social institutions.

The book also employs recurring devices:

• Thought experiments that reappear across chapters to illustrate different aspects of the theory.
• Cross‑referencing between chapters (e.g., responsibility in ch. 6 presupposing the reason‑theoretic framework of ch. 1).
• Progressive refinement: Scanlon restates key ideas (like reasonable rejection) multiple times, each with added nuance.

This structure aims to show how a single conception of reasons and justifiability to others can underwrite a wide range of moral questions, from everyday interpersonal duties to questions of institutional design.

5. The Nature of Reasons in Scanlon’s Framework

Scanlon begins What We Owe to Each Other with a general account of normative reasons, which he takes to be fundamental for understanding morality as well as prudence and other domains of practical thought.

Reasons as Facts That Count in Favor

Scanlon characterizes reasons in a non‑psychologistic way:

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A person has a reason to do something if there is something about the action that counts in favor of doing it.

On this view, reasons are not mere psychological states, such as desires; they are facts or considerations that stand in a normative relation to actions or attitudes. This aligns Scanlon with “object‑given” or “reasons‑first” approaches to normativity.

Against Desire‑Based Theories

Desire‑based or Humean theories hold that all practical reasons ultimately derive from an agent’s desires or preferences. Scanlon argues instead that:

• Desires themselves are often responses to reasons rather than sources of normativity.
• We can intelligibly criticize or revise desires by appealing to independent reasons.
• Some reasons (e.g., not to cause serious harm) seem to apply to us whether or not we currently desire to comply.

Proponents of Humean views respond that desires are needed to explain motivation and to avoid positing mysterious “normative facts,” while Scanlon maintains that his view preserves the phenomenology of deliberation and the possibility of rational criticism.

Types and Structure of Reasons

Scanlon distinguishes between:

• Personal reasons (e.g., reasons to promote one’s own well‑being),
• Moral reasons (rooted in what we owe to others),
• Impersonal reasons (pertaining to values not essentially tied to any one person’s good).

He also discusses weight and relevance of reasons, emphasizing that practical judgment involves assessing which reasons are decisive in a given context, not merely tallying them mechanically.

Reasons and Rationality

For Scanlon, to be rational is roughly to respond appropriately to reasons one has. Rationality is thus conceptually downstream from reasons, not the other way around. This sets the stage for contractualism: the key question becomes what reasons individuals have to reject or accept candidate moral principles, given their status as separate persons with lives of their own.

6. Contractualism and the Test of Reasonable Rejection

The core of Scanlon’s ethical theory is his contractualist account of wrongness. He offers a characteristic formula:

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An act is wrong if its performance under the circumstances would be disallowed by any system of rules for the general regulation of behavior that no one could reasonably reject as a basis for informed, unforced, general agreement.

The Standpoint of Mutual Recognition

The “no one could reasonably reject” test is to be applied from the standpoint of mutual recognition, where each person sees others as separate rational agents entitled to justification. This standpoint shapes what kinds of reasons matter: self‑interest can count, but only insofar as it can be pressed as a claim compatible with equal recognition of others.

Reasonable Rejection

A principle may be reasonably rejected when there is a sufficiently strong generic complaint that a person (or type of person) could make about the burdens it imposes. The test asks:

• What burdens would this principle impose on individuals in various positions?
• Are these burdens such that someone in that position would have reason, from a perspective of mutual recognition, to reject the principle?

Scanlon emphasizes “generic” descriptions to avoid focusing on idiosyncratic preferences or specific individuals; what matters is the kind of situation and burden.

Distinction from Other Contract Theories

Reasonableness vs. Actual Agreement

Scanlon’s test does not require actual consensus. It asks what no one could reasonably reject, given the relevant facts and mutual recognition. Critics argue about how determinate this standard is, while defenders claim it captures the justificatory structure of many everyday moral judgments: we seek principles that we can justify to each person potentially affected, and we consider whether their complaints would be reasonable.

7. Value, Well-Being, and Moral Justification

Scanlon devotes substantial attention to clarifying how value and well‑being bear on moral reasons, without reducing morality to the promotion of value.

Distinctions Among Kinds of Value

He distinguishes:

• What is good (valuable states of affairs, objects, activities),
• What is good for a person (contributing to that person’s well‑being),
• What we have reason to do (which may, but need not, aim at maximizing the above).

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We should not assume that the central question of ethics is what things are good, and how good they are.

This contrasts with classical utilitarianism, which identifies moral rightness with maximizing aggregate good (usually understood as well‑being or preference satisfaction).

Critique of Purely Desire‑Based and Welfare‑Maximizing Views

Scanlon argues against views that define value entirely in terms of desire satisfaction or subjective preferences, suggesting that:

• People can have mistaken or uninformed desires.
• Some things (e.g., friendship, knowledge) seem valuable even if not currently desired.
• The way someone’s life goes can be better or worse for them independently of their momentary mental states.

At the same time, he does not treat value as a mysterious, wholly independent realm; instead, he sees judgments of value as grounded in reasons we can articulate and share.

Value Within Contractualism

Within the contractualist framework:

• Considerations of well‑being and value-for-persons enter as part of the complaints individuals can raise against principles.
• The seriousness of a complaint depends on how a principle affects a person’s opportunities for a good life.
• However, contractualism resists aggregation of value across persons in the way utilitarianism does; value helps determine how bad a burden is for a given person, not how to sum across many people.

Alternative interpretations suggest that, in practice, contractualism may rely heavily on value judgments similar to those of sophisticated consequentialists, differing mainly in how they are combined and compared. Debates continue about whether Scanlon’s distinctions are sufficient to avoid collapsing his theory into a disguised maximizing view, or whether they preserve a distinctive focus on justifiability to individuals rather than overall value.

8. Non-Aggregation, Complaints, and the Problem of Numbers

A distinctive feature of Scanlon’s contractualism is its resistance to simple aggregation of benefits and burdens across persons. Instead, he evaluates principles in terms of individual complaints.

Complaints, Not Sums

On Scanlon’s view, to compare two candidate principles we examine the strongest generic complaints that individuals could make under each principle. The question is not “Which principle yields the greatest total or average well‑being?” but rather “Whose complaint under which principle is more serious?”

This leads to the idea that:

• A serious harm to one person may not be justifiably imposed merely to avoid many minor inconveniences to others.
• Each person’s complaint is assessed separately; they are not simply added into a social sum.

The Problem of Numbers

A central challenge is how contractualism handles cases where numbers seem to matter. For example, many philosophers think there is reason to save a very large number of people from moderate harm rather than a smaller number from similar harm.

Scanlon’s approach allows numbers to matter indirectly:

• If two people face identical serious harms, and a principle favors saving only one, each of the unrescued has a complaint that might be stronger than those under a principle that saves more.
• The comparative strength of individuals’ complaints can reference how many people are subjected to which burdens under each principle, without summing welfare.

Critics argue that this may either fail to capture the intuitive importance of numbers in extreme cases (e.g., “lifeboat scenarios”) or smuggle aggregation back in through the back door. Defenders contend that contractualism can treat numbers as relevant to the structure of complaints—e.g., fairness, risk distribution, or the probability that any given person will face a burden—without adopting a straightforward utilitarian calculus.

Small Harms to Many vs. Great Harm to a Few

Scanlon discusses cases where a great harm to a few is set against trivial harms to many. He suggests that the complaint of someone facing great harm may be more serious than any complaint arising from minor inconveniences, no matter how numerous. Opponents argue that, for sufficiently large numbers, aggregation seems morally compelling; contractualists reply that respecting individuals as separate persons supports limits on trading off serious interests against small ones.

The treatment of numbers thus remains one of the most discussed and contested aspects of Scanlon’s theory.

9. Responsibility, Intention, and Moral Permissibility

In What We Owe to Each Other, Scanlon links moral responsibility and permissibility to the reasons and intentions underlying actions, rather than solely to outcomes. This is developed within the contractualist framework.

Intention vs. Mere Foreseeability

Scanlon argues that an agent’s intention can affect the permissibility of an action even when outcomes are similar. For example, intentionally harming someone as a means to an end may be harder to justify under unrejectable principles than allowing comparable harm as a side effect of pursuing an important and permissible goal.

He connects this to what others can reasonably complain about:

• If one is used merely as a means, the complaint may be stronger than if one is harmed as a foreseen but unintended side effect.
• Principles allowing intentional harm in certain ways may be more reasonably rejected than principles permitting comparable side‑effect harms under strict conditions.

This resonates with, but does not simply reproduce, the Doctrine of Double Effect in traditional ethics.

Foreseeability, Control, and Responsibility

Responsibility, on Scanlon’s view, is closely tied to what an agent could reasonably have been expected to foresee and control, given justifiable principles. If harm results from factors outside an agent’s reasonable control, the basis for moral criticism is weaker.

He distinguishes:

• Permissibility: whether the action violated unrejectable principles.
• Blameworthiness or criticism: which additionally involves the agent’s attitudes, intentions, and responsiveness to reasons.

While What We Owe to Each Other focuses more on permissibility, it already sketches this responsibility‑based distinction that Scanlon later develops further.

Doing vs. Allowing Harm

Scanlon examines whether there is a morally significant distinction between doing and allowing harm. Within his framework:

• A principle permitting certain omissions (allowing harm) may be less reasonably rejectable than one permitting equivalent active harming, because the structure of individuals’ complaints differs.
• However, the doing/allowing distinction is not treated as absolute; what matters is how different patterns of action and omission can be justified to each affected person.

Critics question whether Scanlon can explain these distinctions without appealing to prior non‑contractualist intuitions, while supporters argue that his focus on individuals’ standpoint and reasonable rejection provides a unified explanation of why intention and responsibility matter morally.

10. Moral Motivation and Justifiability to Others

Scanlon devotes a chapter to moral motivation, aiming to show how his contractualist theory can explain why people care about acting rightly.

The Desire to Be Justifiable to Others

Scanlon proposes that a central element of moral motivation is the desire:

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to be able to justify one’s actions to others on principles they could not reasonably reject.

This is not a mere desire for social approval, but a concern rooted in recognizing others as rational agents with equal standing. According to Scanlon:

• Many of us are moved by a wish to stand in justifiable relations to others.
• This desire can motivate compliance with demanding moral requirements even when these conflict with self‑interest.

Contrast with Alternative Accounts

Critics argue that some agents, especially moral saints or deeply altruistic individuals, may be motivated by concern directly for others’ welfare rather than by justifiability per se. Others doubt whether the desire to justify oneself is psychologically universal. Proponents respond that Scanlon is offering a normative idealization of moral motivation that fits many everyday experiences of guilt, apology, and justification.

Internalism and the Link Between Reasons and Motivation

Scanlon adopts a moderate form of internalism: if a person is fully rational and informed, recognition of sufficient moral reasons will typically connect with motivation, partly through this desire for justifiability. However, he also allows that people can fail to be moved by reasons because of weakness of will or distorted attitudes, without thereby losing the normative force of the reasons.

Moral motivation, on his account, is thus an interplay of:

• The normative structure of reasons (including moral reasons grounded in what we owe to each other), and
• A characteristic human concern to be able to justify one’s conduct to others whose claims one recognizes.

11. Personal Relationships, Partiality, and Special Duties

One of Scanlon’s key tasks is to show how special obligations—to friends, family, associates—fit within a theory that begins from equal moral standing of persons. Chapter 7 addresses this by examining how partiality can be justified under principles no one could reasonably reject.

Justified Partiality

Scanlon argues that principles must allow for certain forms of reasonable partiality:

• People have strong interests in maintaining personal relationships (friendships, family ties) and in giving these relationships special weight.
• Individuals could reasonably reject principles that required them to treat everyone with strict impartiality, disregarding special responsibilities to loved ones.

Thus, contractualism supports principles that permit, for example, giving some preference to the needs of one’s children or close friends, as long as this does not amount to unfair neglect or exploitation of others.

Special Duties and Associative Obligations

Scanlon considers associative duties arising from roles (e.g., professional roles, citizenship) and ongoing relationships. Within his framework:

• Such duties are grounded in the value these associations have for their members and for their participants’ projects.
• Others would have reason to reject principles that undermine the stability and integrity of these associations.

He distinguishes between:

Tensions with Impartiality

Some critics maintain that contractualism either:

• Fails to justify strong enough special obligations (e.g., to family or compatriots), or
• Risks undermining impartial respect for persons if it accommodates robust partiality.

Scanlon’s response is that the contractualist test itself mediates this tension: partiality is acceptable insofar as principles permitting it cannot be reasonably rejected by anyone, including those who do not benefit from the partial treatment. The strength of others’ complaints sets limits to how far partiality may go.

Debates continue over whether this strategy adequately captures national partiality, obligations to co‑nationals, or strong duties of loyalty, which may have more controversial implications when evaluated from a standpoint of mutual recognition.

12. Applications to Social and Political Morality

Although primarily a work of moral theory about individual conduct, What We Owe to Each Other also explores implications for social and political morality, especially in its later chapters.

From Interpersonal Duties to Institutions

Scanlon extends the contractualist test to institutions and social practices by asking which systems of rules structuring society could not be reasonably rejected. This includes questions about:

• Distributive justice: allocation of economic resources, opportunities, and life prospects.
• Legal and political institutions: structures of rights, liberties, and decision‑making procedures.
• Social norms: conventions governing, for example, free speech, privacy, and tolerance.

The method is continuous with the interpersonal case: one compares individuals’ generic complaints against competing institutional principles.

Relation to Rawls and Political Liberalism

Scanlon’s approach has affinities with Rawlsian theories of justice:

• Both emphasize justification to each person, equality, and fairness.
• Both avoid grounding political principles in aggregated welfare.

However, Scanlon’s focus remains on what individuals owe to one another rather than on a fully developed conception of political justice. Some commentators view his contractualism as providing a moral background that could complement more explicitly political frameworks, while others question whether it can alone deliver detailed institutional prescriptions.

Policy and Public Reasoning

In applied debates, Scanlonian contractualism has been taken up (often by others) to address issues such as:

• Risk regulation and imposition of risks on populations.
• Health care distribution and priority‑setting.
• Fairness in taxation and public spending.
• Rights to freedom of expression and association.

The framework suggests that legitimate policies are those whose underlying principles cannot be reasonably rejected by any affected person, once all are given appropriate weight as separate individuals.

Critics argue that the test may be underdeterminate in large‑scale policy contexts, where many different distributions of burdens and benefits might be defended as unrejectable. Supporters reply that even if contractualism does not uniquely settle every institutional question, it offers a distinctive person‑centered constraint on permissible policies by ruling out those that impose intolerable burdens on some merely to produce aggregate gains for others.

13. Key Concepts and Technical Terms

What We Owe to Each Other introduces or refines several technical terms that structure Scanlon’s theory. Many of these are now widely used in moral philosophy discussions.

These concepts interlock: for example, generic complaints are assessed from the standpoint of mutual recognition to determine whether a principle is subject to reasonable rejection, thereby fixing permissibility.

14. Famous Passages and Illustrative Cases

Several passages and examples from What We Owe to Each Other have become central reference points in contemporary ethics.

The Contractualist Formula

Scanlon’s repeated formulation of his central claim is widely quoted:

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An act is wrong if its performance under the circumstances would be disallowed by any system of rules for the general regulation of behavior that no one could reasonably reject as a basis for informed, unforced, general agreement.

This statement, appearing in Chapter 4, encapsulates the contractualist approach to wrongness.

Mutual Recognition

Another often‑cited passage articulates the idea of mutual recognition, where persons regard one another as entitled to justification rather than as objects of benevolent concern or instruments of social welfare. Although formulations vary across the chapter, this theme is central to the book’s self‑conception and is frequently mined for discussions of respect and interpersonal justification.

Complaints vs. Aggregation

Chapter 5 contains influential discussions contrasting individual complaints with aggregative reasoning. Scanlon uses stylized cases where many people suffer minor inconveniences and a few suffer major harms, arguing that focusing on generic complaints rather than sums can better capture our intuitions about moral seriousness. While the book does not always present these as single named thought experiments, these scenarios are frequently distilled in the secondary literature as paradigmatic “Scanlonian” cases.

Doing and Allowing, and Intention

Chapter 6 offers cases testing distinctions between doing and allowing harm, and between intended and merely foreseen harm. These are used to explore whether principles permitting certain actions could be reasonably rejected. The cases are often invoked in broader debates about the Doctrine of Double Effect and the moral relevance of intention.

Personal Relationships

In Chapter 7, Scanlon’s examination of how contractualism treats friendship and family includes examples of choices between helping a stranger versus a close friend, or giving priority to familial duties over general beneficence. These passages are commonly cited in discussions of partiality and special obligations.

Commentators differ on which examples are philosophically most illuminating; some emphasize the aggregation cases in Chapter 5, others the subtle interpersonal cases in Chapters 6 and 7. Nonetheless, these passages collectively illustrate how Scanlon applies the contractualist test to concrete moral problems, shaping subsequent work in normative ethics.

15. Philosophical Method and Argumentative Style

Scanlon’s method in What We Owe to Each Other is characteristic of late 20th‑century analytic moral philosophy but has distinctive features that have drawn both praise and criticism.

Reflective Equilibrium and Intuitive Testing

The book proceeds via reflective equilibrium:

• Starting from widely shared moral judgments and intuitions (e.g., about harm, responsibility, partiality).
• Developing general principles (contractualism, accounts of reasons and value).
• Testing and revising both principles and judgments in light of conflicts.

Thought experiments and concrete cases function as tests of candidate principles of right and of the contractualist framework itself.

Reasons‑First and Non‑Metaphysical

Methodologically, Scanlon adopts a “reasons‑first” approach: instead of deriving reasons from other normative or metaphysical notions, he treats them as primitive. He also avoids heavy metaphysical commitments about moral facts, focusing instead on the practical role of reasons and justification in our deliberation.

Some commentators describe his approach as a form of constructivism about moral principles (since they are justified by a process of reasonable rejection), while others emphasize that he takes reasons themselves to be stance‑independent in important respects.

Argumentative Style

Scanlon’s style is:

• Careful and incremental, frequently restating distinctions and clarifying possible misunderstandings.
• Highly analytic, with fine‑grained distinctions (e.g., different types of reasons, different formats of complaint).
• Non‑rhetorical: he rarely uses dramatic language or appeals to emotion, instead relying on detailed reasoning.

Readers sometimes find the prose demanding because of its density and level of abstraction, but it is widely regarded as exemplary in its precision and seriousness.

Use of Counterexamples and Comparisons

The book systematically compares contractualism with:

• Utilitarian and other consequentialist views,
• Desire‑based accounts of reasons,
• Alternative contract and Kantian theories.

Scanlon frequently develops counterexamples to rival theories (especially involving aggregation and well‑being) and invites analogous pressure on his own view, often openly acknowledging unresolved difficulties, particularly around numbers and indeterminacy.

This combination of system‑building with self‑critical argument has contributed to the work’s status as a central text in contemporary ethics.

16. Reception, Criticisms, and Ongoing Debates

Upon publication in 1998, What We Owe to Each Other was quickly recognized as a major contribution to moral philosophy. It has since become a standard reference point in debates about reasons, contractualism, and non‑consequentialist ethics.

Initial and Ongoing Reception

Early reviewers in leading journals praised the book’s systematic scope and clarity, noting its distinctive focus on justifiability to individuals rather than aggregate welfare. It has been widely adopted in graduate seminars and advanced undergraduate courses, and it features prominently in overviews of normative ethics and metaethics.

Philosophers such as Derek Parfit, R. Jay Wallace, Rahul Kumar, and others have engaged extensively with Scanlon’s ideas, often developing sympathetic but critical interpretations. Parfit’s On What Matters devotes substantial space to comparing Scanlonian contractualism with rule consequentialism and Kantian moral theory.

Key Criticisms

Major lines of criticism include:

1. Indeterminacy and Practical Guidance
   Critics argue that the standard of what “no one could reasonably reject” is too vague to deliver determinate verdicts in complex cases. Different people, or different theorists, may reasonably disagree about the seriousness of complaints or what mutual recognition requires.

2. Numbers and Aggregation
   Many philosophers contend that contractualism struggles with large‑number cases or must reintroduce aggregative ideas indirectly. Some think it underestimates the moral importance of numbers; others argue that the theory covertly relies on quasi‑utilitarian reasoning.

3. Scope and Special Obligations
   There is debate over whether Scanlon’s framework can adequately justify strong partiality to family, compatriots, or co‑nationals. Some critics believe it is either too restrictive of partiality or too permissive, thereby undermining equal respect.

4. Motivational and Psychological Realism
   Skeptics question whether the desire to be justifiable to others is a sufficiently universal or primary moral motive, suggesting that many forms of moral behavior are better explained by emotions, social practices, or evolutionarily shaped dispositions.

5. Political and Structural Justice
   Some argue that What We Owe to Each Other does not fully address structural injustices, systemic oppression, or collective responsibility. They maintain that a more overtly political, institutional approach (e.g., Rawlsian or critical theory) is needed.

Continuing Debates

Current discussions explore:

• Whether Scanlonian contractualism can be extended to population ethics, risk regulation, and climate policy.
• How it compares to neighboring views, such as Parfit’s triple theory or various forms of Kantian constructivism.
• Whether refinements (for example, more structured accounts of reasonable rejection or generic complaints) can resolve worries about indeterminacy and numbers.

Despite disagreements, the book remains central in discussions of what it means to treat persons as separate centers of agency and to ground morality in justifiable principles rather than in maximizing impersonal value.

17. Legacy and Historical Significance

What We Owe to Each Other is widely regarded as one of the most influential works in late 20th‑century moral philosophy, with a legacy extending across normative ethics, metaethics, and political philosophy.

Impact on Normative Ethics

The book crystallized Scanlonian contractualism as a major alternative to consequentialism and deontology in their classical forms. It helped shift the focus of ethical theory toward:

• Person‑centered justification rather than maximizing impersonal value,
• The role of reasons and complaints in moral argument,
• Non‑aggregative conceptions of how to compare harms and benefits across persons.

Subsequent work frequently positions itself relative to Scanlon’s framework, either defending variants of contractualism, proposing hybrid views, or offering rival accounts of interpersonal justification.

Influence on Metaethics and Theory of Reasons

Scanlon’s non‑psychologistic conception of reasons has been foundational for the modern “reasons first” approach in metaethics. Philosophers working on normativity, rationality, and practical reasoning—such as Parfit, Wallace, and others—have engaged deeply with his account.

The book also contributed to the now‑standard distinctions among different kinds of value and reasons (personal, moral, impersonal), influencing debates on well‑being, desire theories, and value pluralism.

Contributions to Political and Legal Theory

Although not primarily a work of political philosophy, What We Owe to Each Other has informed discussions of:

• Distributive justice and the ethics of risk,
• Rights‑based approaches in legal theory,
• Public reasoning and justification in liberal democracies.

Contractualist ideas are often invoked in arguments about fair procedures, priority to the worst‑off, and the legitimacy of imposing risks or burdens on particular individuals.

Position in the History of Moral Philosophy

Historically, the book is seen as:

• A post‑Rawlsian development of contract‑based morality, emphasizing individual complaints rather than hypothetical agreements in an original position.
• A significant bridge between Kantian respect for persons and contemporary analytic theories of reasons and value.
• A key contribution to the long‑standing debate over the separateness of persons and the limits of aggregation, following Sidgwick, Rawls, and others.

Its influence is reflected in ongoing scholarship, numerous symposiums and edited volumes, and the incorporation of Scanlonian contractualism into standard taxonomies of ethical theories. Even critics often adopt its vocabulary—of reasonable rejection, generic complaints, and mutual recognition—underscoring the lasting impact of the conceptual framework introduced in What We Owe to Each Other.