Dr Francesca Perlman

This paper introduces the field of social epidemiology and some of its leading theories, identifies the philosophies that underpin them, describes the advantages of making these philosophies explicit, and considers the definition of a theistic worldview in relation to this field. Finally, it gives conclusions and practical steps for research.

Social epidemiology and its theories

Social epidemiology is "the branch of epidemiology that studies the social distribution and social determinants of health”. A familiar example is the study of socioeconomic health inequalities, whereby socially disadvantaged individuals experience lower life expectancy and higher rates of many diseases.

Several theories have been proposed for the effects of social and economic conditions on health, three of which are considered here:

  • Psychosocial - psychological reactions to adverse social conditions ultimately result in the abnormally regulated production of stress hormones, which in turn harms physical health.
  • Materialist - worse material conditions amongst the disadvantaged (e.g. the physical effects of deprivation, higher rates of alcohol consumption and smoking) lead to higher rates of disease.
  • Neomaterialist - the presence or lack of social structures and supports in a society, such as the welfare state, influence its citizens’ health.

(Two other leading theories not discussed further here are: life course, where socially determined exposures of any kind at different stages of life affect subsequent wellbeing; and selection, where ill health leads to a decline in socioeconomic status.)

Although there is some empirical evidence to support each of the theories above, the evidence to date appears insufficient to support a single one. Two examples of current debate are:

(1) The causes of higher mortality rates in countries in which income inequalities are greater. The two principal explanations proposed are either that where inequalities are greater, there is more hostility and shame felt by the disadvantaged, and greater social breakdown (psychosocial) [Wilkinson]or that social infrastructures are worse in more unequal societies (neomaterial) [Lynch].

(2) The causes of the sharp increase in mortality after the fall of communism in Russia and Eastern Europe. The two principal explanations are either excess alcohol consumption (material) [Leon]or stress due to rapid social change (psychosocial) [Bobak, Marmot 1996].

Philosophical influences, and the role of materialism

Whilst it is well-recognised that material factors (such as alcohol or smoking) are harmful to health, or that harmful hormone release is provoked by a stressful situation, there appear to be philosophical assumptions that go beyond the empirical evidence. Not all researchers may be aware of these assumptions, however.

The key philosophy here is materialism (sometimes also known as naturalism or physicalism), which states that only material, or physical, things exist. Particularly relevant to the theories above are a materialist view of the mind and of history:

  • Evolutionary psychology The proposed psychological mechanisms in psychosocial theories of social epidemiology are frequently derived from evolutionary psychology, in which human behaviour is believed to arise from adaptations to the environments of our early human ancestors. Evolutionary psychology is based on a view of the mind that is modular, with modules that consist of evolved cognitive mechanisms, each based on complex neural structures and interactions. Furthermore ideas may spread through populations as “memes”, ideas or cultural patterns, the mind equivalent of a physical gene [Dawkins]. Evolved mind processes can affect physical health, and in the field of health inequalities, poor health is believed to result from the poor adaptation of humans to unequal societies. Specific mechanisms proposed include the stressful experience of feeling shame at one’s low social position. Parallels with worse health in low status baboons in primate communities are cited [Sapolsky].
  • Reductive/”strict” materialism A reductionist materialist view would state that since only physical factors exist, only physical factors (such as smoking or alcohol) can influence health. In a “reductionist materialist” mind, consciousness and mental states result purely from chemical and electrical processes in the brain [Dennett], mental processes cannot influence physical functioning, and memes do not exist. Non-material influences on health (such as psychosocial factors) are therefore excluded a priori.
  • Historical materialism Neomaterial theories, whereby social structures influence health, appear to be influenced by Marx’s notion of historical materialism [Marx]. Marx defined history as “matter in motion”, and believed that social structure and conditions influenced people’s thinking and behaviour. Economic determinism is a related concept, where a society’s economic system influences behaviour. Whilst the mechanism for an effect on the mind (or on health) is not clear, it is relevant that Marx believed that human action occurred in direct response to social stimulus, acting through a mind that was simple and mechanistic in function.

Advantages of acknowledging the philosophical influences

The lively and passionate debates in social epidemiology appear initially to focus on interpretation of scientific findings, with the underlying differences in metaphysical belief either unrecognised or unacknowledged.

This is perhaps not surprising. Passionately held metaphysical beliefs may influence one’s worldview to the extent that other viewpoints may be automatically discounted. In the words of geneticist and materialist Richard Lewontin, “We are forced by our a priori adherence to material causes to create an apparatus of investigation and a set of concepts that produce material explanations, no matter how counter-intuitive, no matter how mystifying to the uninitiated...”[Lewontin].

Thus, worldview (whether materialist or any other) may dictate how research questions are framed, and empirical findings inconsistent with that view may be rejected. Genuine incomprehension between researchers of different metaphysical viewpoints may exist, and may progress to serious misunderstandings and strained relationships.

Acknowledging and discussing the metaphysical influences openly would allow open discussion of their controversial nature. Materialism is only one of many philosophies, and academics who are non-materialists do not necessarily have religious beliefs. Its controversial nature, even within social epidemiology, is further emphasised by the disagreements between the proponents of psychosocial and “strict” materialist theories.

General criticisms of materialist philosophy are that the vastly complex subatomic nature of matter makes it hard to understand what “material” means any more, and that a materialist view of the mind finds difficulty in accounting for phenomena such as consciousness and subjectivity [Ward, Lennox]. Furthermore, materialism does not allow for personal explanations, which are necessitated by the existence of conscious minds [Ward]. At the individual level, this would include choice of behaviour or action (e.g. why do people choose to smoke), and at the societal level (e.g. national differences in countries’ historical paths, such as how the welfare state developed historically, or how the transition from communism proceeded).

Specific criticisms of evolutionary psychology and meme theory are that they offer “just-so” explanations for a wide variety of human behaviours, and that memes are poorly defined, and without empirical evidence for their existence.[Stove, Rose]

Further advantages of more open discussion of philosophical assumptions would enable greater awareness of the influence they have on research methods, and allow clearer differentiation from and interpretation of empirical findings, and also to promote better understanding between academics.

Applying a “theistic” worldview to social epidemiology

Since philosophy is an important influence on research, and no-one is metaphysically “neutral”, it is important for a Christian academic to have a clear and explicit philosophical viewpoint in relation to social epidemiology. This must include the key aspects, as seen above, of the nature of the human mind, society and history. Here I describe my own “theistic” worldview relevant to social epidemiology, based on a Judaeo-Christian understanding of God and man, in God’s image, derived from the Bible. (It is important to note that each Christian academic should reach their own considered view, however):

  • The nature of the human mind allows for the possibility of free will, subjective opinion, and choice as to our response to circumstances.
  • Behaviour is the product of personal choice, and is not dictated by physical brain processes. Human choices can be harmful or beneficial to ourselves, others and to society.
  • Societal structures are influenced by past actions and choices of their citizens. Societies are inevitably imperfect, even though improvement is possible.
  • The existence of a spiritual realm means that the world is not limited to physical and material things.

As stated previously, clarifying philosophical influences, helps open up our own viewpoint to critical outside discussion. It also helps us see how it differs from other perspectives. For example, aspects of this view are clearly at odds with materialists, some of whom may be explicitly atheistic. For example Richard Lewontin continues his statement above “...Moreover, that materialism is absolute, for we cannot allow a Divine Foot in the door”[Lewontin] . Finally, it must be emphasised again that empirical findings and metaphysical assumptions are clearly separated, whether theistic, materialist or any other.

Practical conclusions and suggestions for research

In this paper I have demonstrated the important role of philosophical belief in social epidemiology. I believe therefore, that the approach of a Christian working in this field should focus on:

  • Awareness of current scientific theories and their underpinning philosophies (notably materialism)
  • Differentiating empirical scientific research findings from metaphysical assumptions.
  • Being aware of the criticisms and controversy surrounding materialism
  • Developing a clear worldview as a Christian, and understanding how it relates to established theories and other philosophies, and where the differences lie.

Following on from these conclusions, I make these practical suggestions for research:

  • Identifying, developing and testing theories that are compatible with our considered worldview (e.g. models that allow the effects of material and non-material factors, or psychosocial models where the psychological mechanisms are based on a view of the mind that allows for choice and free will).
  • Explicitly testing our own and others’ theories, actively seeking to disprove them, following Karl Popper’s definition that a scientific theory must be falsifiable. (the temptation is to research theories that support one’s worldview)
  • Researching the empirical effect of individual factors on health without assuming a particular philosophy (e.g. testing the effect of a material variable such as alcohol, but also allowing for the effect of non-material factors)
  • Promoting metaphysical discussion in a context of relationship building: getting to know our colleagues, their work and beliefs and worldview. In a context of a long history of heated debate, it is important to find opportunities to challenge and discuss colleagues’ beliefs and metaphysical assumptions sensitively.
  • At the same time, seeking allies, colleagues whose viewpoint is compatible, even if not identical, to ours, and seek opportunities for collaboration.

Further reading
This reading list is not comprehensive, but is intended to provide broad direction for further study.

  • Bobak M, Marmot M. East-west mortality divide and its potential explanations: proposed research agenda. BMJ 1996;312:421-5.
  • Dawkins, R. The Selfish Gene. New York: Oxford University Press , 1976
  • Dennett, D. Consciousness Explained. New York: Penguin, 1992
  • Leon DA, Chenet L, Shkolnikov V, Zakharov S, Shapiro J, Rakhmanova G et al. Huge variation in Russian mortality rates 1984-94: artefact, alcohol, or what? Lancet 1997;350:383-8.
  • Lynch JW, Davey Smith G, Kaplan GA, House JS. Income inequality and mortality: importance to health of individual income, psychosocial environment or material conditions. BMJ 2000; 320: 1200–4
  • Wilkinson RG. Income distribution and life expectancy. BMJ 1992;304:1658.
  • Lennox, J. God’s Undertaker: has science buried God. Oxford: Lion Hudson 2007
  • Lewontin, R Billions and Billions of Demons Review of Carl Sagan’s book “The Demon-Haunted World: Science as a Candle in the Dark” . New York Review of Books, 1997 (Jan 9)
  • K. Marx, A Contribution to the Critique of Political Economy, Progress Publishers, Moscow, 1977
  • Rose, H, Rose, S (Eds). Alas Poor Darwin: Arguments against evolutionary psychology. New York: Harmony Books, 2001
  • Sapolsky, R.M. The Influence of Social Hierarchy on Primate Health Science 2005;308:648
  • Stove, D. Darwinian Fairytales: Selfish genes, errors of heredity and other fables of evolution. Aldershot, Avebury Press 1995, repr. New York: Encounter Books, 2006
  • Ward, K. Why there is almost certainly a God: Doubting Dawkins. Oxford: Lion, 2008