Transplant Problem

1. Introduction

The Transplant Problem is a thought experiment in moral and medical ethics in which a surgeon can save several dying patients only by killing one healthy person and using that person’s organs. It is typically framed so that there are no side effects beyond the deaths and survivals themselves, making the numerical trade‑off stark: one life lost versus more lives saved.

The case functions as a focused test for moral theories that evaluate actions by their consequences, especially act utilitarianism, which tends to endorse sacrificing one for many when doing so maximizes overall welfare. At the same time, the scenario appears to bring out widely shared intuitions about rights, constraints on killing, and the moral significance of treating persons as mere means to others’ ends.

Philosophers employ the Transplant Problem to examine several connected issues:

• whether it is ever permissible to kill an innocent person to save a greater number;
• how to understand the distinction between killing and letting die;
• whether individual rights or side‑constraints can block seemingly beneficial trade‑offs;
• how clinical roles and professional norms shape moral permissions in medicine.

The case is often discussed alongside the Trolley Problem but is designed to heighten features that many people regard as morally problematic: direct, intentional killing; using a person as a resource; and intimate, medical settings. Because of these features, the Transplant Problem has become a standard tool in contemporary moral philosophy and bioethics for probing the limits of consequentialist reasoning and exploring alternative, non‑consequentialist frameworks.

2. Origin and Attribution

The Transplant Problem is most commonly attributed to the American philosopher Judith Jarvis Thomson. It appears in her influential article:

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Judith Jarvis Thomson, “Killing, Letting Die, and the Trolley Problem,” The Monist, Vol. 59, No. 2 (1976).

In that paper, Thomson introduces what she calls the “Transplant” or “Organ Transplant” case as a deliberate counterpart to trolley‑style scenarios. Her aim is to explore whether the same intuition that supports diverting a trolley to save more lives also supports killing one person for organs, and if not, why not.

Although Thomson’s 1976 formulation is the canonical source, some scholars note that structurally similar sacrificial cases appeared earlier in discussions of utilitarianism, such as in Henry Sidgwick’s late 19th‑century work and mid‑20th‑century debates about wartime triage or sacrificing one for many in rescue situations. However, these earlier treatments did not typically involve organ transplantation or the specific clinical context that Thomson emphasizes.

The table below highlights key early textual anchors:

Subsequent authors frequently credit Thomson when deploying the Transplant Problem, though they may adjust details (number of patients, organs, or institutional setting). Some occasionally use alternate labels such as “Doctor and the Five Patients” or “Sacrificial Transplant Scenario,” but these are generally treated as variations on Thomson’s original case rather than independent inventions.

3. Historical Context in Moral and Medical Ethics

The Transplant Problem emerged in the mid‑1970s, at the intersection of two developments: analytic debates about moral theory and rapidly evolving medical practices, particularly organ transplantation.

Philosophical Context

In late 20th‑century analytic ethics, philosophers were intensively examining:

• the status of consequentialism, especially utilitarianism;
• the killing vs. letting die distinction;
• the moral relevance of using persons as means.

Works by Philippa Foot, John Taurek, and others were questioning whether numbers alone could justify sacrificing individuals. Thomson’s Transplant case entered a live discussion shaped by trolley‑style dilemmas and the emerging view that precise, stylized thought experiments could illuminate the structure of moral theories.

Medical and Bioethical Context

Concurrently, organ transplantation was becoming a realistic and increasingly common medical procedure. Advances in surgery and immunosuppression in the 1960s and 1970s raised intricate questions about:

• criteria for death (e.g., the move toward brain‑death standards);
• allocation of scarce organs;
• the limits of consent, bodily integrity, and donor rights.

These developments contributed to the consolidation of bioethics as a distinct field, with dedicated journals, hospital ethics committees, and legal frameworks. Within this environment, hypothetical cases involving organ use were a natural vehicle for probing the boundaries of acceptable clinical practice.

Convergence of Debates

The Transplant Problem thus reflects a convergence:

Within this context, Thomson’s scenario could draw on public awareness of transplantation while idealizing away legal and institutional complications, isolating a sharp moral question about killing one to save many.

4. The Transplant Scenario Stated

In its standard form, the Transplant Problem describes a stylized medical situation with carefully controlled conditions.

Core Narrative

A highly competent surgeon is treating five patients in a hospital. Each patient needs a different vital organ—typically a heart, two lungs, a liver, and a kidney—and each will die very soon without a transplant. There are no donor organs available, and routine avenues for procurement have been exhausted.

A healthy individual comes to the hospital for a minor check‑up or routine examination. Tests reveal that this person’s organs are perfectly compatible with all five dying patients. The surgeon realizes that, by killing this individual and distributing the organs, she could save the five.

The scenario stipulates that:

• the killing can be carried out secretly and safely;
• there will be no legal consequences or discovery;
• there will be no erosion of public trust or deterrence from seeking medical care;
• every relevant outcome is known with certainty.

Thus the only morally significant outcomes, as described, are:

Central Question

Under these idealized conditions, the question is whether the surgeon:

• is morally permitted, required, or forbidden to kill the healthy person to save the five.

The description is intentionally narrow. It abstracts from emotional, legal, or social consequences to generate a sharp conflict between:

• maximizing the number of lives saved, and
• respecting constraints on killing or using individuals as means.

Different theories interpret the significance of this stylization in different ways, but the baseline scenario remains relatively constant across philosophical discussions.

5. Logical Structure and Dialectical Purpose

The Transplant Problem is structured as an intuition pump designed to test how moral principles apply under conditions where consequences and options are tightly controlled.

Logical Structure

A common reconstruction of the argument embedded in the scenario runs as follows:

1. A surgeon can either:
   • allow five patients to die, or
   • kill one healthy person to save the five.
2. All non‑moral facts are stipulated so that outcomes are certain and there are no further side effects.
3. Act utilitarianism holds that the morally right action is the one that maximizes overall welfare.
4. Killing one to save five yields a better aggregate outcome (more lives saved).
5. Therefore, act utilitarianism appears to imply that the surgeon ought to kill the healthy person.
6. Yet many people experience a strong intuition that such killing is morally impermissible.
7. Persistent, considered intuitions that conflict with a theory’s verdict supply prima facie pressure against that theory, or at least call for an explanation.

From these premises, the scenario supports the conclusion that there is a tension between straightforward maximizing consequentialism and widespread moral judgments about killing in medical contexts.

Dialectical Purpose

Philosophers use the case for several dialectical purposes:

Proponents of consequentialism may respond by revising the theory, appealing to indirect or rule‑based versions, or challenging the reliability of the intuition. Non‑consequentialists may treat the scenario as evidence for deontological side‑constraints or robust individual rights.

The thought experiment thus serves as a focal point in debates about how to balance the demands of aggregation with respect for individual persons.

6. Relation to the Trolley Problem Family

The Transplant Problem is frequently discussed as part of the Trolley Problem family of thought experiments, yet it introduces notable contrasts.

Structural Similarities

Both Trolley and Transplant scenarios:

• involve a choice between allowing multiple deaths or causing a single death;
• are framed with idealized certainty about outcomes;
• are intended to test whether it is morally acceptable to sacrifice one to save many;
• are used to probe tensions between consequentialist and deontological viewpoints.

Because of these similarities, some authors treat Transplant as a variant of the trolley family, asking whether the same principles that seem to justify diverting a trolley would also justify killing for organs.

Key Differences

Nevertheless, philosophers highlight several contrasts:

Advocates of a principled distinction argue that these differences may justify divergent moral judgments: it may be permissible to redirect an existing harm (trolley) while impermissible to initiate harm (transplant) even for the sake of numbers.

Dialectical Role within the Family

Within the broader trolley literature, Transplant functions as a stress test:

• If a theory says “sacrifice one to save five” in both trolley and transplant, it faces charges of endorsing intuitively extreme actions.
• If a theory says “yes” in trolley but “no” in transplant, it must articulate what morally relevant difference underlies this asymmetry.

The interplay between trolley and transplant cases has therefore driven substantial work on distinctions such as redirecting vs. initiating harm, doing vs. allowing, and means vs. side‑effects.

7. Utilitarian and Consequentialist Responses

Consequentialist approaches offer diverse reactions to the Transplant Problem, depending on whether they focus on individual acts, rules, or broader indirect effects.

Act Utilitarianism

Act utilitarians generally hold that the right action is the one that maximizes overall well‑being in each specific case. Applied to Transplant:

• Proponents often conclude that the surgeon ought to kill the healthy person, since this produces a net gain of four lives.
• Some defend this verdict as a theoretical insight, suggesting that revulsion at the act reflects emotional bias, evolutionary heuristics, or social conditioning rather than moral truth.
• Others acknowledge the intuitive cost but argue that consistency demands accepting such implications where the numbers are clear.

Rule Utilitarianism and Rule Consequentialism

Rule utilitarians and rule consequentialists ask which rules, if generally followed, would maximize welfare. On this view:

• A rule allowing doctors to kill healthy patients for organs is expected to have disastrous long‑term effects (loss of trust, avoidance of hospitals, abuse).
• A strict rule prohibiting such killing is said to promote overall well‑being.
• Therefore, even if in this idealized one‑off case killing might appear beneficial, the surgeon should not operate, because she must follow welfare‑maximizing rules rather than case‑by‑case calculations.

Some critics argue that the scenario’s stipulation of “no bad side effects” makes it difficult for rule consequentialists to rely on such real‑world considerations, prompting them to emphasize the role of internalization of rules or the importance of stable moral dispositions.

Indirect and Sophisticated Consequentialism

Other consequentialists, such as advocates of indirect or sophisticated consequentialism, maintain that:

• agents should not always calculate utilities directly;
• instead, they should adopt decision procedures and character traits (e.g., strong aversion to killing innocents) that tend to be optimific overall.

In Transplant, they might say the morally best decision procedure would lead the surgeon not to kill, even if the act‑consequences in the stylized scenario seem favorable. This approach attempts to reconcile consequentialist foundations with common judgments while acknowledging that our intuitive responses may be tracking the long‑run value of trustworthy, non‑predatory medical institutions.

Overall, consequentialist responses range from straightforward endorsement of the killing to more nuanced accounts that preserve prohibitions against such acts through rules, dispositions, or indirect evaluations.

8. Deontological and Rights-Based Interpretations

Deontological and rights‑based theories often take the Transplant Problem to illustrate the existence of robust moral constraints that do not depend solely on consequences.

Rights Against Being Killed and Used

Many rights theorists claim that individuals possess stringent rights to life and bodily integrity. On this view:

• The healthy person in Transplant has a right not to be killed and not to be used merely as a resource for others.
• These rights function as side‑constraints, limiting what may be done to a person even for very great benefits to others.

Thus, the surgeon’s proposed action is seen as a violation of the healthy person’s rights, regardless of the number of lives that could be saved.

Kantian Perspectives and “Using as a Mere Means”

Kantian interpretations emphasize the formula of humanity: treat persons always as ends in themselves, never merely as means. In Transplant:

• The healthy patient is intentionally killed so that their organs may save the five.
• This is characterized as treating the person merely as a means, failing to respect their autonomous status.

Kantian‑inspired accounts argue that such use is categorically impermissible, even when it would maximize well‑being.

Non-Consequentialist Constraints on Killing

Deontologists frequently posit agent‑centered constraints against killing the innocent. These constraints may be:

• Absolutist: killing an innocent person is never permissible as a means to an end.
• Non‑absolutist: killing is almost never permissible, and certainly not in the kind of straightforward trade‑off envisioned in Transplant.

Under either model, the surgeon is forbidden to kill the healthy person, not because of predicted outcomes, but because of the type of act involved.

Distinguishing Transplant from Other Trade-offs

Rights‑based and deontological theorists use Transplant to articulate fine‑grained distinctions:

These interpretations treat the Transplant Problem as support for moral principles that limit aggregation and underscore the moral inviolability of individuals.

9. Killing, Letting Die, and Using as a Means

The Transplant Problem is a central case for examining three interconnected moral distinctions: killing vs. letting die, doing vs. allowing, and using as a means vs. side‑effect.

Killing vs. Letting Die

In the scenario, the surgeon faces:

• actively killing one healthy person, or
• allowing five patients to die from their illnesses.

Many theorists argue that there is a morally relevant difference between causing someone’s death and merely failing to prevent it. On this view:

• Killing is typically more seriously wrong than letting die, even when the numerical outcomes favor killing.
• Transplant illustrates this by pitting one killing against five lettings‑die and eliciting the intuition that the killing remains impermissible.

Critics question whether this distinction can bear such weight, especially when inaction predictably results in multiple deaths.

Doing vs. Allowing

Closely related is the doing/allowing distinction:

Proponents of a strong doing/allowing distinction hold that moral agents are more tightly constrained in what they may do to others than in what they may allow to happen, even when they can foresee the outcomes.

Using as a Means vs. Side-Effect

The case also emphasizes whether the victim is used as a means:

• The healthy person’s death is not an unfortunate by‑product; it is instrumentally necessary for saving the five, since their organs must be removed.
• This contrasts with scenarios where harm comes as a foreseen side‑effect of pursuing a good end.

Drawing on the Doctrine of Double Effect, some philosophers argue:

• It is impermissible to intend someone’s death as a means.
• It may be permissible to foresee but not intend harm as a side‑effect under certain conditions.

In Transplant, the surgeon’s intention is precisely to bring about the healthy patient’s death to obtain the organs, placing the act on the “means” side of this distinction.

Together, these distinctions provide competing explanations of why many judge the surgeon’s killing impermissible, even when more lives could be saved. Debates continue over whether these distinctions are defensible, coherent, and consistent across different cases.

10. Key Variations and Related Medical Cases

The core Transplant scenario has generated numerous variations and related medical thought experiments that test the robustness of intuitions and principles.

Structural Variations

Philosophers modify case features to explore which elements drive moral judgment:

Some variations examine whether the healthy individual is already dying from another cause, raising questions about double effect and organ harvesting from patients near death.

Related Medical Thought Experiments

Several well‑known cases are structurally related:

• The Emergency Room Case: A doctor can avoid a riot or disaster by framing and killing one innocent patient, highlighting similar trade‑offs between killing and preventing multiple deaths.
• Hospital Switch / Organ Lottery: All patients entering a system face a small risk of being selected and killed to provide organs for many. This emphasizes institutional rules and long‑term expectations.
• Triage Cases: A doctor must allocate scarce resources (e.g., ventilators) among multiple patients, where saving some precludes saving others, but without actively killing any patient for parts.

Though not always involving organ transplantation, these cases explore comparable tensions between individual inviolability and aggregate welfare.

Clinical Analogues

Real‑world practices occasionally echo aspects of the thought experiment, though without intentional killing for transplantation:

• Organ donation after circulatory or brain death raises questions about when procurement becomes killing.
• Living donation (e.g., kidney, liver lobe) illustrates consented bodily sacrifice for others.
• Allocation protocols for scarce organs and ICU beds involve life‑and‑death prioritization without direct killing.

Philosophers use these real and hypothetical variants to investigate whether principles that appear compelling in the abstract can be coherently applied across different medical contexts.

11. Standard Objections and Critical Debates

The Transplant Problem has provoked substantial critical discussion, both about its philosophical construction and its implications for moral theory.

Objections to the Scenario Itself

Several criticisms target the design of the thought experiment:

1. Unrealistic Idealization
   Critics argue that stipulating away social, legal, and psychological effects (e.g., loss of trust in medicine) strips consequentialism of key resources. On this view, the case is so remote from real clinical practice that its evidential value about moral theories is limited.

2. Biasing Intuitions
   Some contend that the case is constructed to elicit a strong emotional aversion—through intimate violence and betrayal by a physician—thus “rigging” our intuitions against the consequentialist verdict.

3. Inconsistent Intuitions Across Cases
   Empirical and philosophical work suggests that people’s judgments about Transplant and related trolley cases may be unstable or sensitive to framing, leading some to question whether they are reliable guides to moral truth.

Debates About Theoretical Implications

Philosophers also dispute what the case shows, if anything, about moral theory:

Some consequentialists accept the counter‑intuitive verdict (kill the healthy person) and argue that moral progress may require acknowledging such implications. Others modify consequentialism (e.g., via rules or agent‑relative reasons) to avoid endorsing the killing.

Non‑consequentialists draw on Transplant to support rights and constraints, but face challenges in explaining exactly why similar trade‑offs in other settings (e.g., wartime decisions, public health policies) might seem permissible.

Demands for a Principled Distinction

A major ongoing debate concerns whether there exists a principled difference between:

• Transplant (where most say it is wrong to sacrifice one), and
• certain trolley cases (where many say it is permissible to sacrifice one).

Proposed distinctions include redirecting vs. initiating threats, personal force, intention, and the structure of agency. Each proposed principle faces test cases designed to probe its plausibility and consistency, driving a large literature of refinements and counterexamples.

12. The Role of Moral Intuitions and Methodology

The Transplant Problem is central to methodological debates about how moral theories should engage with intuitions elicited by thought experiments.

Intuitions as Data

Many philosophers treat our considered responses to cases like Transplant as data points in ethical theorizing. On this approach:

• A theory that repeatedly clashes with firm, reflective intuitions (e.g., that the surgeon must not kill the healthy patient) is prima facie suspect.
• Thought experiments help isolate morally relevant features and test candidate principles by checking whether they reproduce judgments across a range of scenarios.

This methodology is often associated with reflective equilibrium, in which one aims to adjust both general principles and particular judgments to achieve coherence.

Skepticism About Intuitions

Others are more skeptical about relying heavily on intuitions in extreme, artificial scenarios:

• They argue that such reactions may be shaped by evolutionary biases, cultural norms, or emotional salience rather than moral truth.
• Experimental findings showing framing effects and cross‑cultural variation are taken to suggest that intuitions are noisy and context‑dependent.

From this perspective, a theory like act utilitarianism need not be overturned merely because it yields a counter‑intuitive verdict in Transplant; instead, intuitions may be candidates for revision.

Balancing Theory and Case Judgment

Methodological positions vary along a spectrum:

Transplant is thus not only a substantive ethical problem but also a meta‑ethical tool for reflecting on how we should build and test moral theories. The debate over its proper methodological role remains active, particularly as empirical studies of moral judgment become more integrated into philosophical practice.

13. Implications for Bioethics and Health Policy

While the Transplant Problem is an idealized case, it has influenced thinking in bioethics and health policy by clarifying limits on acceptable trade‑offs in medicine.

Professional Ethics of Physicians

The scenario foregrounds the physician’s role:

• Most bioethical frameworks hold that doctors must not intentionally kill patients, even to save more lives.
• The case helps articulate duties of non‑maleficence, respect for autonomy, and fidelity to individual patients, highlighting perceived conflicts with pure outcome maximization.

Discussions of Transplant contribute to codes of medical ethics that stress the prohibition on using patients as means to others’ ends.

Organ Procurement and Allocation

Though real transplant practice does not involve killing for organs, the thought experiment informs debates about:

• criteria for death in organ donation (e.g., brain death, circulatory death);
• the “dead donor rule,” which forbids organ removal that itself causes the donor’s death;
• whether any relaxation of such rules risks moving toward Transplant‑like practices.

In allocation policy, the case underscores that deciding who receives organs is distinct from deciding whom to sacrifice to obtain them, reinforcing the moral salience of the killing vs. prioritizing distinction.

Public Trust and Institutional Design

Health policy analysts invoke Transplant to highlight the role of public trust:

• Real‑world concerns about fear and avoidance of care are often cited as reasons to maintain strict prohibitions against sacrificing individuals.
• The case has been used pedagogically to illustrate why institutional safeguards, informed consent requirements, and transparent allocation procedures are necessary.

Population-Level Trade-offs

Beyond transplantation, the scenario informs discussions of:

• pandemic triage (allocation of ventilators or ICU beds);
• public health measures that impose risks on some for the sake of many.

Policy debates use Transplant as a vivid boundary marker, suggesting that while certain risk impositions may be justified, intentional killing of specific individuals as a means to societal benefit is widely regarded as beyond the pale in legitimate health policy.

Overall, the case functions less as a realistic policy proposal and more as a conceptual limit case that helps clarify what kinds of trade‑offs bioethics and health policy are prepared to countenance.

14. Contemporary Developments and Empirical Studies

Recent decades have seen both theoretical refinements of the Transplant Problem and a growing body of empirical research on how people respond to it.

Theoretical Refinements

Contemporary philosophers have:

• Proposed more nuanced accounts of intentionality, causal structure, and agency to explain why Transplant differs from other trade‑offs.
• Developed complex doctrines (e.g., “triple effect,” “moral relevance of contact,” “structural asymmetry”) to capture patterns in case‑based judgments.
• Integrated Transplant into broader frameworks such as contractualism, virtue ethics, or hybrid theories that combine consequentialist and deontological elements.

These developments often use Transplant as one among many test cases to evaluate how well a theory tracks or systematizes intuitive reactions.

Experimental Philosophy and Moral Psychology

Empirical work, especially in experimental philosophy and cognitive science, has examined lay and expert responses to Transplant‑type scenarios:

These studies are used both to support intuition‑skeptical views (highlighting instability and bias) and to investigate whether stable, underlying principles can be extracted from noisy data.

AI Ethics and Decision Systems

The Transplant Problem has also been adapted in discussions of artificial intelligence and algorithmic decision‑making, for example:

• exploring how an AI in charge of resource allocation should balance aggregate welfare against individual protections;
• questioning whether machine systems should ever be designed to endorse Transplant‑like sacrifices.

Although these applications are typically abstract, they show how the scenario continues to inform debates about the ethical programming of decision systems.

Overall, contemporary work extends the Transplant Problem beyond purely armchair reflection, integrating it into interdisciplinary research that spans philosophy, psychology, neuroscience, and technology ethics.

15. Legacy and Historical Significance

Since its introduction in the 1970s, the Transplant Problem has become a canonical thought experiment in moral philosophy and bioethics.

Influence on Moral Theory

The scenario has:

• Played a central role in debates over act vs. rule utilitarianism, stimulating the development of more sophisticated consequentialist frameworks.
• Provided a vivid illustration of deontological side‑constraints and rights, helping to articulate and defend non‑consequentialist theories.
• Contributed to the refinement of key distinctions—killing vs. letting die, doing vs. allowing, means vs. side‑effect—that structure much of contemporary ethical theory.

Its persistent use in textbooks, articles, and classroom discussions reflects its perceived power to crystallize fundamental normative tensions.

Role in Bioethics Education

In bioethics and medical ethics, Transplant serves as a teaching tool:

• It appears in curricula for medical students, nursing programs, and ethics committees as a way to introduce complex issues about patient rights, professional obligations, and resource allocation.
• It has helped shape a shared vocabulary around the idea that certain acts—like intentionally killing one patient for another’s benefit—mark moral “red lines” for healthcare professionals.

Placement Within the Trolley Tradition

Within the broader trolley problem tradition, Transplant has functioned as a key “anchor point,” against which new variations are measured. Its enduring presence has spurred an extensive literature seeking principles that can account for the contrasting intuitions it elicits compared to other cases.

Continuing Relevance

The scenario continues to be cited in discussions of:

• emergency triage and pandemic responses;
• public trust in institutions;
• the design of ethical AI and autonomous systems.

Although no real‑world policy endorses transplant‑style killing, the thought experiment endures as a reference point in evaluating proposals that push toward more aggressive forms of consequentialist reasoning.

Historically, the Transplant Problem exemplifies the power of carefully constructed thought experiments in late 20th‑ and early 21st‑century analytic philosophy: by focusing attention on a stark hypothetical, it has shaped the trajectory of debates about the moral significance of individuals, the permissibility of sacrifice, and the limits of outcome‑based ethics.