Defining ‘health’ and ‘disease’

Abstract

How should we define ‘health’ and ‘disease’? There are three main positions in the literature. Naturalists desire value-free definitions based on scientific theories. Normativists believe that our uses of ‘health’ and ‘disease’ reflect value judgments. Hybrid theorists offer definitions containing both normativist and naturalist elements. This paper discusses the problems with these views and offers an alternative approach to the debate over ‘health’ and ‘disease’. Instead of trying to find the correct definitions of ‘health’ and ‘disease’ we should explicitly talk about the considerations that are central in medical discussions, namely state descriptions (descriptions of physiological or psychological states) and normative claims (claims about what states we value or disvalue). This distinction avoids the problems facing the major approaches to defining ‘health’ and ‘disease’, and it more clearly captures what matters in medical discussions.

Introduction

How should we define the terms ‘health’ and ‘disease’? This is a central problem in the philosophy of medicine and an important issue in bioethics. There are three main philosophical approaches to defining ‘health’ and ‘disease’. Naturalists (Kendell, 1975, Boorse, 1976, Boorse, 1977, Boorse, 1997, Scadding, 1990) desire definitions based on scientific theory. Their definitions attempt to highlight what is biologically natural and normal for humans. Normativists (Margolis, 1976, Goosens, 1980, Sedgewick, 1982, Engelhardt, 1986) believe that our uses of ‘health’ and ‘disease’ reflect value judgments. Healthy states are those states we desire, and diseased states are those states we want to avoid. Hybrid theorists (Reznek, 1987, Caplan, 1992, Wakefield, 1992) define ‘health’ and ‘disease’ by combining aspects of naturalism and normativism. Their aim is to provide an account of health and disease that captures the virtues but not the vices of naturalism and normativism.

As we shall see, all three approaches to defining ‘health’ and ‘disease’ are problematic. Naturalism does not satisfy its own desideratum of providing naturalistic definitions of ‘health’ and ‘disease’. Normativism attempts but fails to capture how the terms ‘health’ and ‘disease’ are used by lay people and medical practitioners. The hybrid approach, like naturalism, incorrectly assumes that we can give a scientific account of the natural states of organisms. There is also a more systematic problem underlying the debate over defining ‘health’ and ‘disease’. When discussing controversial medical cases, two factors are salient: the physiological or psychological states of patients, and the values we attach to those states. Naturalists focus on physiological and psychological states—whether an organ or system is normal or properly functioning. Normativists focus on whether a psychological or physiological state is valued or disvalued. The debate is regrettably polarized: naturalism and normativism each focus on only one of the two factors that are important when discussing medical cases. Hybrid theorists do consider both components, but they do so in an overly restrictive way. For the hybrid theorist, disease only occurs when a state is both dysfunctional and disvalued. As a result, the hybrid approach to ‘health’ and ‘disease’ too quickly shuts down the discussion of controversial cases.

We could keep looking for the correct definitions of ‘health’ and ‘disease’, but this paper advocates a different approach. Instead of trying to find the correct definitions of ‘health’ and ‘disease’ we should explicitly talk about the considerations that are central in medical discussions, namely state descriptions (descriptions of physiological or psychological states) and normative claims (claims about what states we value or disvalue). Using this distinction avoids the problems facing the major approaches to defining ‘health’ and ‘disease’. Furthermore, this distinction more clearly captures what matters in medical discussions.