1. Conceptions of Health & Disease ISD I – E/H/HL Session 1 April 14, 2003

2. Overview Since you’re in the early days of the ISD course, it’s a good time to consider the concepts of disease & health How should we conceive of them? The main question for this part of the session: Are these descriptive or normative notions? i.e., is a value judgment made whenever judgments about health and disease are made or are these simply objective, value-free descriptions of a patient?

3. Some Examples Which of the following are examples of disease or ill health? Which are neither? AIDS Senility Extremely short stature SARS Colour blindness Starvation

4. Why Does Defining Health & Disease, Matter? 1. The basic concepts we work with often shape our thinking in ways we might not expect This idea will be explored at several points in the term 2. Significance for the scope of medicine Medicine is generally thought to be in the business of promoting health, curing disease, etc. Thus the limits of disease, health, etc. set the limits of medicine Consider, e.g., the debate about whether alcoholism is a disease

5. Two Examples Contrast “Health is a state of complete physical, mental and social well-being and not merely the absence of disease or infirmity.” (Preamble to the WHO Constitution) “Health is a state of physical well-being” (Daniel Callahan) Notice the huge difference in the scope of health care implied by the two definitions

6. The Relationship between Disease & Health Are disease and health logical opposites? I.e., is health just the absence of disease? This doesn’t allow for degrees of healthiness Does being healthy really require the complete absence of disease? If so, we’ll either need a fairly restrictive definition of disease or else no one will ever be healthy

7. Three Approaches to Defining Disease & Health 1. In terms of statistical normalcy/ abnormality 2. In terms of proper biological functioning 3. In normative terms

8. Normative vs. Non-normative Conceptions of Disease & Health What’s at stake in the argument about whether disease and health are normative concepts? Some claim that medicine cannot be objective unless its basic concepts are value-judgment free However, recall that some think value judgments can be objectively true or false If you accept that (at least some) value judgments are objectively correct, this usually limits your discomfort with the idea that health & disease are normative concepts

9. Statistical Normalcy/Abnormality Healthy conditions are statistically normal conditions Diseases are statistically abnormal conditions Is this plausible? This idea is often appealed to, but clearly flawed Abnormal tallness is a disease? Unusual hair or eye colour constitutes a disease?

10. Proper Function “health consists in our functioning in conformity with our natural design as determined by natural selection” (66) If an organ “loses the capacity to perform the function for which it was designed by evolution…, the condition is indicative of disease” (66) Is this plausible?

11. Problems with Proper Function The very idea seems to anthropomorphize evolution. Does it make sense to talk about function where there’s no conscious designer? Notice: this problem goes away if you accept the existence of God as active creator Even if we speak loosely about function, couldn’t there be normal diseases? E.g., Consider that aging might be very useful from an evolutionary point of view Would this mean no diseases as a result of ‘ordinary’ aging?

12. Normative Conceptions of Health & Disease A normative conception claims “it is impossible to decide whether a particular state of affairs represents health or disease without some reference to values” (68) Culver & Gert: “it is not dysfunction but the perceived evil associated with dysfunction that is at the heart of the meaning of disease.” (69) Such a conception may also draw on ideas of function or abnormality, but it is value judgments that are claimed to be at the heart of judgments about disease or health Is this plausible?

13. So What? Most of the time, the fact that health & disease are value-laden terms is not problematic since most of the time we agree about how to evaluate a particular condition E.g., heart problems = bad Problems do arise, however, in some cases in which there are disagreements about how we should evaluate a particular condition E.g., deafness homosexuality p.m.s.

14. The Point None of this suggests that there is anything fundamentally wrong with the concepts of disease & health It does suggest that it is a mistake to think the concepts are purely descriptive They have a normative element we should be aware of

15. A Further Question Even if we accept that the concept of disease has normative elements, it still remains for us to come up with a precise definition of disease Two Competing Conceptions of Disease Disease entity Focuses on the existence of a discrete, physical disease entity Clinical ‘entity’ Conceives of disease in functional terms