Where does new theory come from?

Short abstract

Establishing a theory of population health will depend on researchers giving up their disciplinary narrowness.

It is certainly a good ambition to clarify through a glossary how we use words like theory, model, hypothesis, and research question. The authors should be commended for trying. However, I found their views on the building of new theory not convincing.

(1) The whole approach to theory seems somewhat unrealistic. One crucial aspect is missing, in my view. Does theory come from an orderly process, like when we build a house, starting with the foundation, then the load bearing walls, etc? Here, “theory building” is depicted as starting with a framework (where does the framework come from?), then moving to theory that is later tested in a model. It seems to me that the birth of new theory is a much more chaotic process, the characteristics of which we should learn to recognise.

A 100 years ago last year Einstein's theories about light and relativity were formulated. A visit to the Einstein exhibition in Berlin last summer convinced me that his theories were the result of the fierce conflict between old and new schools of thought, and the inability of both these schools to accommodate empirical (experimental) results in a consistent way. For instance, there was no consensus whatsoever about any framework (“a set of variables and the relations among them”, according to the glossary), from which one could have built his theory that light exists in the form of discrete units, quanta (today known as photons). Consequently the theory was immediately rejected; it was only reluctantly accepted as it solved the problem of explaining the photoelectric effect.¹

Surely, this is a much more typical situation, in which a new theory is likely to emerge. The sceptical response from large parts of the scientific community is not unusual either. A new theory is more similar to a sudden leap out of a persistent and controversial research problem, than to the building of a house brick by brick. More like a frog leaping out of the pond.

Applying this to population health we should expect that theoretical development is more likely to come from research areas where we have controversy about specific issues of substance, rather than from controversy between theoretical schools of thought in general. For instance, does sharp income inequality in a country contribute to increased levels of circulatory mortality in that country? Around this issue, economists, epidemiologists, historians, psychologists, and sociologists continue to argue. By throwing oneself into the argument with empirical data, or with wild ideas, or with systematic reviews, one is likely to promote theory about social inequality and health. It seems less likely that all good researchers will first unite around a framework and then build a theory together. Yet one crucial empirical study (or more likely several crucial studies) could shift the whole discussion towards consensus. Observation (a term not found in the glossary) and theory develop together.

I agree that the slow process of repeating studies, correcting previous mistakes, designing new studies, collecting evidence, adding detail, changing minor aspects, and refining concepts is a bit more like the building of a house; and certainly those processes are equally important in the long run. Thus there is a place for orderly brick by brick work to advance theoretical problems. But here also, one is most likely to advance if one focuses on anomalies, inconsistencies, and inherent conflicts in what is believed to be the known, and how this is conceptualised.

(2) For many years now, the social sciences have been plagued by a large amount of quasi‐philosophical jargon of doubtful value. The most embarrassing example for us who have a social science background was revealed by Sokal² who managed to publish a faked nonsense‐theoretical paper. Obscure language from social science sources played a key part in his successful attempt. Sometimes the approach to theory in the social sciences (and not only there) has resembled the building of churches, or empires, focusing on advancing the teaching and language of certain leading lights, rather than on the testing of their ideas against empirical evidence.

The formation of schools of thought is perhaps inevitable; but they often form around a mixture of ideological and scientific arguments. Labelling of one's own school of thought with a fancy name and that of the opponents with a less fancy name (the most popular one for your opponent is “positivist”) is therefore a bad tradition, which we should try to avoid. It does not add to any substantial argument, rather the opposite in my view. It is far from clear from this guide and glossary why we should be interested in “postpositivist theory building” rather than any other view on theory. Terms like observation, evidence, and causality are all missing from the glossary, perhaps this is significant?

My own view is that a theory of population health will depend on researchers giving up their disciplinary narrowness. In the words of Mervyn and Ezra Susser we should try to integrate “causal pathways at the societal level….with pathogenesis and causality at the molecular level.³ Not an easy task, but a very necessary one.