1. What is Philosophy of Medicine?
Philosophy of Medicine is a specialisation of philosophy of science — it investigates the concepts and methodologies of specific sciences from a normative point of view (i.e. how science should ideally work).
- Born in the 1940s (Vienna Circle, Logical Positivism)
- Philosophy of Medicine as a distinct field: born in the 1970s, increasingly important today
- It has its own specialised journals, courses, and professorships
Classic questions in philosophy of science:
- What is a scientific theory?
- Are scientific theories representations of the world, or merely tools for modifying it?
- Can science be value-free?
- What is causality? What is a scientific law?
Philosophy of Medicine vs. Bioethics
| Discipline | Core Question | Domain |
|---|---|---|
| Bioethics | What is the right thing to do? | Research, clinical practice |
| Philosophy of Medicine | What are the fundamental concepts and methods of medicine? | Epistemology, ontology of medicine |
Key connection
These are not independent: every conceptual/methodological choice in medicine has ethical consequences.
2. Philosophical Problems
Definition
A philosophical problem is one for which there exist multiple compelling and competing views, and which cannot be answered straightforwardly by empirical means.
Examples across domains:
- Ethics: the Trolley Problem
- Metaphysics: do abstract objects exist?
- Mind: what is pain? what is consciousness?
- Medicine: what are health and disease?
David Foster Wallace — This is Water (2005)
“What the hell is water?” — The most obvious and important realities are often the ones hardest to see and define.
Philosophy is an activity: a way of thinking that uses logical arguments, critiques existing arguments, and analyses and clarifies concepts.
3. What Can Philosophy of Medicine Do for Medical Doctors?
Practical value
- Help understand basic concepts from outside one’s own paradigm
- Answer questions that cannot be settled by evidence alone
- Recognise that some fundamental scientific concepts are value-laden — their definition and extension depend on ethical or practical reasons
4. What is a Disease? — The Central Question
Candidate definitions (intuitive):
- Whatever doctors take care of?
- Whatever is included in medical nosologies?
- What makes people suffer?
- A physical condition with a negative impact on survival?
- A physical condition with a negative impact on functionality?
- A physiologically abnormal condition?
- An undesirable and disadvantageous physical condition?
Why does this question matter? Whether a condition is classified as a disease has consequences for:
- Research funding and priorities
- Health policies
- How people perceive their own experience (validation vs. stigma)
- How society regards the condition
Concepts are rules for thinking and acting — different concepts of disease → different goals for medicine → different actions.
5. Disease, Illness, and Sickness (Twaddle, 1979)
5.1 Disease
- The malady from the doctor’s point of view
- Basic phenomena: physiological, biochemical, genetic, and mental entities/events
- Objective: can be observed, examined, mediated, measured
- Goal: classify, detect, control, treat, and cure
5.2 Illness
- The malady from the patient’s point of view
- Basic phenomena: subjective experience — anxiety, fear, pain, suffering
- Access through: introspection, phenomenology, verbal reports
- Subjective, but accessible via narrative
- Goal: comfort, care, relief of suffering
5.3 Sickness
- The malady from the social/institutional point of view
- Basic phenomena: expectations, conventions, norms, social roles
- Intersubjective: knowledge shared by a social group
- Determines: entitlement to treatment, sick leave, legal accountability
- Can carry covert norms → stigma and discrimination
Sickness and covert norms
- Myocardial infarction carries higher prestige than fibromyalgia among doctors
- Homosexuality was classified as a disease for decades → experienced as stigmatising
- Obesity can lead to discrimination in healthcare and society
Summary Table
| Disease | Illness | Sickness | |
|---|---|---|---|
| Field | Medical profession | Personal/experiential | Society, institutions |
| Phenomena | Physiological, genetic, mental | Subjective suffering, pain | Social conventions, norms, roles |
| Access | Observation, measurement | Introspection, phenomenology | Social studies, participation |
| Knowledge | Objective | Subjective | Intersubjective |
| Goal | Cure | Care | Resource allocation, justice |
| Entitles to | Examination, treatment | Attention, support | Economic support, sick leave (but also: discrimination) |
6. Facts and Values
6.1 The Fact/Value Distinction
Descriptive vs. Normative Concepts
- Descriptive concepts (e.g. gold, prime number, araucaria, sister): based on facts
- Normative concepts (e.g. good, bad, cruel, murder, sexy, mature): based (also) on values, norms, preferences, interests
David Hume Values cannot be derived or read off from facts alone. We need principles to connect facts and values.
6.2 Faultless Disagreement
In contemporary philosophical debate, disagreements based on values are called “faultless disagreements”:
- Both parties may be fully aware of the relevant facts
- Yet they still disagree — because the disagreement is about values, not facts
- Providing more facts will not settle the issue
Practical example
- Factual disagreement: “Dental services are free for ISEE < €20,000” vs. “No, it’s €8,000” → resolvable by checking the Ministry website
- Value disagreement: “It is right to limit free dental care to the poorest” vs. “Basic dental care should be universal” → requires ethical reasoning, not just fact-checking
7. Two Main Philosophical Positions on Disease
The Two Poles
Naturalism Normativism Core claim Disease = dysfunction of physiological systems Disease = disvalued state causing harm/suffering Concept type Purely descriptive, non-evaluative Constitutively evaluative Primary focus Disease (objective entity) Illness (individual experience) Epistemic priority Disease over illness Illness over disease
Two Intermediate Positions
- Hybridism: diseases are dysfunctioning physiological systems that bring harm to those with the dysfunction
- Value-conscious naturalism: diseases are dysfunctions of systems, but values may be needed to apply the concept to particular cases (e.g. setting thresholds)
8. Naturalism: Boorse’s Biostatistical Theory (BST)
BST Definition (Boorse, 1977)
Disease is “an internal state in which normal functional capacity is impaired — that is, in which one or more organic functions operate at a level below typical efficiency — or in which functional capacity is reduced due to environmental agents.”
Key Concepts
Function:
The causal contribution that entities and processes in a system make to the organisation and capabilities of that system.
Example: The normal function of pancreatic -cells is to produce insulin, which controls blood glucose levels and contributes to glucose homeostasis. In Type 1 DM, -cells are destroyed → insulin production → disease.
Typical Efficiency / Normality:
Determined by comparing the subject’s functional values to those of other subjects in the same reference class (same sex, same age group).
Example: To assess kidney function, measure eGFR and compare it to the average for women of the same age:
Example — Phenylketonuria (PKU):
- Genetic disorder → deficiency/absence of phenylalanine hydroxylase (PAH)
- PAH normally metabolises phenylalanine (Phe) from food
- In PKU: Phe accumulates → toxic → cognitive impairment, seizures
- In the vast majority of people, PAH functions normally
- → PKU = biological function operating well below typical efficiency → pathological condition ✓
Pros of BST
| Measurable | Scientific | Objective | Cross-species | Limits over-medicalisation |
|---|---|---|---|---|
| ✓ | ✓ | ✓ | ✓ (animals, plants) | ✓ |
9. Objections to Naturalism
9.1 The Reference Class Problem
The Reference Class Objection (Kingma, 2007, 2014)
Nature itself does not divide people into reference classes. We choose reference classes based on pragmatic/valuative considerations.
Example: Why is (woman, age 50+) a valid reference class for estrogen, but (woman, with Down syndrome) is not? → Because Down syndrome is already assumed to be a pathology — so BST is circular: it smuggles in value judgements to define the very reference classes it uses to define disease.
Additional issue: race in nephrology
- The eGFR equation historically included a race correction factor for Black patients
- Race is a socio-political construct, not a fixed biological variable
- Using it perpetuates structural racism and health inequities
- → Many centres now use race-free eGFR equations
9.2 The Threshold Problem (Canguilhem)
Georges Canguilhem — Le normal et le pathologique (1966)
The frontier between normal and pathological is imprecise across different individuals simultaneously, but extremely precise for one individual considered over time.
Key claims:
- Anomaly ≠ Pathology: diversity is not disease. Pathological implies pathos — a direct feeling of suffering and impotence, a sense of impeded life.
- A living being is normal in a given environment insofar as it is “good enough” relative to that environment
- What is normal under given conditions can become pathological in another situation
The Haemophiliac Case
All functions of the haemophiliac operate similarly to those of healthy individuals — except that bleeding is unstoppable. This is only pathological because animal life normally involves environmental risks (injury). Haemophilia is not an anomaly per se; it becomes disease in the context of a risky environment.
The Threshold Problem — Lumbar Vertebra
Should sacralization of the 5th lumbar vertebra be considered pathological? It only becomes painful late, and in some cases never. Where exactly does anomaly end and disease begin?
Canguilhem’s conclusion: suffering and pain are the key elements of disease — pointing toward normativism.
9.3 The Homosexuality Objection
- Homosexuality was classified as a disease in the DSM for decades
- It was removed — but not because of new empirical discoveries about homosexuality
- What changed were society’s moral views about sexuality
- → BST fails to track historical disease attributions; value changes drive nosological changes
10. Normativism About Disease
Normativist Definition
A physical or mental condition is a disease if and only if it is undesirable: it causes damage, disability, or obstacle to the primary goals of the person.
Analogy: “weed” is an evaluative concept — a plant is a weed only relative to our crops and goals.
- A tumour is a disease (for normativism) because it tends to cause disability and suffering in its bearer
- For naturalism, a tumour is a disease because the affected organ/tissue can no longer contribute its functions at a statistically normal level
Problems for Normativism
Objections
- Many undesirable conditions we would NOT call diseases: being below average height, having a deviated nasal septum without functional impairment, limited tolerance to specific situations
- Who judges what is harmful? Whose values count?
- Relativism: dependence on values of a specific society, which can change
Extreme case: Drapetomania (Cartwright, 1851)
Dr. Cartwright classified the desire of enslaved people to escape as a mental disease — “Drapetomania, or the disease causing Negroes to run away.” This is the reductio ad absurdum of uncritical normativism: it shows that if any disvalued behaviour can be pathologised, the concept of disease loses all constraint.
11. Intermediate Positions
Value-Conscious Naturalism
- Freckles are statistically abnormal but not harmful → not diseases
- Some very small tumours cause no harm → their disease status is debated
- The reference class for infertility as pathological has changed with changes in people’s well-being goals
- The continuum between normal and disease in blood pressure or BMI is broken by considerations of what matters to people
Threshold-setting involves:
- Role of scientific societies, consensus conferences, peer review
- Considerations of risk assessment and ethical-practical consequences
- These intervene not in the definition of disease, but in delimiting its extension in particular cases
12. Controversial Diseases — Examples
12.1 Obesity
- 2013: AMA recognised obesity as a complex, chronic disease requiring medical attention
- Arguments for disease label: more research, more access to care, less blame, better insurance coverage
- Arguments against: BMI is a weak diagnostic criterion (no direct measure of fat mass or functional impairment); disease label may increase stigma; in European welfare states, may not improve access
- Key tension: weight stigma is harmful to health independent of BMI — and ironically may cause weight gain
12.2 Long COVID
- Significant proportion of COVID-19 survivors experience persistent symptoms (fatigue, breathlessness, joint pain, chest pain, cognitive issues)
- At least 4 distinct clinical entities: post-ICU syndrome, post-viral fatigue syndrome, permanent organ damage, long-term COVID-19 syndrome
- Patients themselves made Long COVID visible — knowledge travelled from patient communities through media to formal health channels
- Diagnostic criteria proposed: confirmed, probable, possible, doubtful Long COVID
12.3 Other Controversial Conditions
- Fibromyalgia — contested biological basis, historically low prestige among doctors
- Hypoactive Sexual Desire Disorder (HSDD) — debate on medicalisation of normal variation
- Gaming Disorder — newly included in ICD-11; debate on whether it meets disease criteria
13. Conclusions
Conclusions
- The question of what makes a condition a disease is ontologically and epistemically complex — it involves both facts and values
- This makes it a genuinely philosophical question: reasons for and against come not only from empirical data, but also from principles, interests, and values
- This does not mean medicine is unscientific or corrupt
- We can move beyond the ideal of science without values toward a conception of science that is aware of the non-epistemic reasons that drive it
Topics Covered in This Class
- Philosophical problem — Philosophy of medicine
- Facts and values — Descriptive and normative concepts
- Normativism and Naturalism about disease
- Biostatistical Theory (Boorse): normal function and efficiency
- The threshold problem — The reference class problem
- Normativist criticisms: Canguilhem
- Problems of normativist theories
- Intermediate positions
- Controversial diseases: obesity, Long COVID, fibromyalgia, HSDD, gaming disorder
TLDR
What is Philosophy of Medicine?
A branch of philosophy of science that examines the foundational concepts and methods of medicine from a normative standpoint. Born in the 1970s as a formal academic field, it is closely connected to bioethics: every conceptual choice in medicine carries ethical consequences.
The Core Problem: What is a Disease?
This is a genuine philosophical problem — multiple competing answers exist, and it cannot be settled purely by empirical data. It matters enormously because disease classification shapes research funding, health policy, patient experience (stigma vs. validation), and social entitlements.
Disease / Illness / Sickness (Twaddle)
Three analytically distinct concepts: disease is the doctor’s objective category (biological dysfunction); illness is the patient’s subjective experience of suffering; sickness is the social/institutional role assigned to the unwell person (rights, exemptions, stigma). These three can come apart: someone may have a disease without feeling ill; someone may be ill without a diagnosable disease; and sickness is shaped by cultural norms that can be unjust.
Facts vs. Values
A crucial philosophical distinction: descriptive concepts are grounded in facts; normative concepts are grounded in values. Many seemingly factual claims in medicine are covertly normative. Faultless disagreement — where two parties have all the same facts but still disagree — arises when the disagreement is really about values, which cannot be resolved by adding more data.
Naturalism (Boorse’s BST)
Disease = a biological function operating below typical efficiency for a given reference class (sex, age). Strengths: measurable, objective, scientifically rigorous, limits over-medicalisation. Critical weaknesses: (1) Reference class problem — who we include in a reference class is itself a value choice (Kingma); we cannot choose reference classes neutrally, because we must already exclude pathologies to define normality, making the definition circular. (2) Threshold problem (Canguilhem) — there is no sharp natural boundary between the normal and the pathological; a mere statistical anomaly is not yet disease. (3) Homosexuality case — removal from the DSM was not driven by new biology, but by changing moral values, showing BST does not accurately track how disease attributions are actually made.
Canguilhem’s Normativist Critique
Anomaly ≠ pathology. A living being is normal insofar as it is good enough for its environment. Disease is not simply statistical deviance — it requires pathos: the individual’s subjective experience of suffering and impeded life. The boundary between normal and pathological is imprecise across individuals but precise for a given individual over time. Pain and suffering are the key elements of disease.
Normativism
Disease = a condition that causes harm, disability, or suffering — an inherently evaluative, not purely factual, category. Analogy: “weed” is evaluative (relative to our garden goals). Strengths: explains why values and suffering matter in medicine. Weaknesses: (1) Many undesirable states are not diseases (being short, having a deviated septum); (2) Relativism risk — different societies could pathologise almost anything; (3) Extreme case: Drapetomania (1851) — the desire to escape slavery pathologised as a mental disease — shows how unconstrained normativism can be weaponised.
Intermediate Position (Value-Conscious Naturalism)
The most defensible current position: disease has a biological core (dysfunction) but values inevitably enter when setting thresholds and defining reference classes. This is not a flaw in medicine — it is an honest acknowledgement of how science actually works. Scientific societies, consensus conferences, and ethical reasoning all play legitimate roles in nosology.
Controversial Diseases
- Obesity: The AMA’s 2013 disease designation was driven by utilitarian arguments (more resources, less blame, more research). But BMI is a weak criterion, and the disease label may increase stigma in European welfare contexts. Weight stigma itself is independently harmful to health.
- Long COVID: Patients themselves made this condition visible before formal medicine recognised it, demonstrating that disease categories can emerge bottom-up from patient communities.
- Others: Fibromyalgia, HSDD, Gaming Disorder — all contested, all involving the interplay of facts, values, and social interests.
Bottom Line
The concept of disease is irreducibly both factual and evaluative. Accepting this does not undermine medicine’s scientific rigour — it demands a more sophisticated, self-aware science that explicitly accounts for the values shaping its fundamental categories.