Wednesday, 21 January 2015

Why do we need more than one research method?

The following is the gist of a talk I will give on Monday at an internal student conference.

Why do we need more than one research method? In acting as a Research Degree Tutor, I am often struck by the pick and mix attitude to research methods taken by some PhD students. This stems in part from the breadth and variety of research carried out in the School: itself an admirable thing. Many different approaches are taken, ranging from large scale quantitative research to small scale hermeneutic or narrative or descriptive studies. But the attitude that surprises me is a stance to that range for which I blame Michael Crotty’s book The Foundations of Social Research: Meaning and Perspective in the Research Process.

Crotty’s explanation of the difference of research methods

Crotty distinguishes between methods, methodologies, theoretical perspectives and epistemologies commenting:

It is not uncommon to find, say, symbolic interactionism, ethnography and constructionism simply set side by side as ‘methodologies’, ‘approaches’, ‘perspectives’, or something similar. Yet they are not truly comparable. Lumping them together without distinction is a bit like talking about putting tomato sauce, condiments and groceries in one basket. One feels compelled to say, ‘Hang on a moment! Tomato sauce is one of many forms of condiment. And all condiments are groceries. Let’s do some sorting out here’. [Crotty 1998: 3]

The following table is an instance of such sorting: dividing different approaches between different levels.

He then suggests that higher levels inform lower levels. So constructionism informs symbolic interactionism which motivates ethnography which favours participant observation.

Things are not quite as straight forward as they might be, however, as the higher levels under-determine the lower ones. So it is not simply that choice at a lower level is fixed by and hence explained by a choice at a higher level. It is not a complete answer to why there is variation at the level of methodologies and theoretical perspectives.

But my main worry is the idea that one might select a theoretical perspective or methodology because one had selected an epistemology. In the introduction, the three listed epistemological are summarised thus:

Objectivism is the epistemological view that things exist as meaningful entities independently of consciousness and experience, that they have truth and meaning residing in them as objects (‘objective’ truth and meaning, therefore), and that careful (scientific?) research can attain that objective truth and meaning…Another epistemology-constructionism-rejects this view of human knowledge. There is no objective truth waiting for us to discover it. Truth, or meaning, comes into existence in and out of our engagement with the realities in our world…In subjectivism, meaning does not come out of an interplay between subject and object but is imposed on the object by the subject. [Crotty 1998: 8-9]

It is clear that these express fundamentally contrasting views. Further, they seem to be making general claims about the nature of reality and hence they are conflicting. If one is true, the other two must be false. Hence if it were the case that the explanation of the different lower levels were difference at the highest then those lower levels would inherit the falsity of at least two of the higher level claims. Hence the explanation suggested for why there are different research methods seems to turn on a mistake. Although there are different lower levels, there should not be.

An argument for a single research method

Assuming that Crotty’s easy pick and mix is unsatisfactory, there is a further historically influential picture of the world which suggests that there should be only one research method, whatever it is. This is the picture that underpinned the Logical Positivists’ Encyclopedia of Unified Science. It includes the assumption that the human sciences will eventually be reduced to biology, biology to chemistry and chemistry to physics. Paul Oppenheim and Hilary Putnam expressed this view in their 1958 paper ‘Unity of science as working hypothesis’.

It is not absurd to suppose that psychological laws may eventually be explained in terms of the behaviour of individual neurons in the brain; that the behaviour of individual cells – including neurons – may eventually be explained in terms of their biochemical constitution; and that the behaviour of molecules – including the macromolecules that make up living cells – may eventually be explained in terms of atomic physics. If this is achieved, then psychological laws will have, in principle, been reduced to laws of atomic physics… [Oppenhiem and Putnam 1991: 407]

Oppenheim and Putnam argue that the unity of science is served by ‘microreductions’. These are reductions in which:

The objects in the universe of discourse of [the reduced science or theory] are wholes which possess a decomposition into proper parts all of which belong to the universe of discourse of [the reducing science or theory]. [Oppenhiem and Putnam 1991: 407]

Since microreduction is construed as the only serious possibility for the unity of science, and since its success rests on a number of other things being the case, the goal of unification has a number of presuppositions which are then outlined. The list begins:

1. There must be several levels. 
2. The number of levels must be finite. 
3. There must be a unique lowest level… 
4. Any thing of any level except the lowest must possess a decomposition into things belonging to the next lowest level…

This list suggests the following view of nature. The world is made up of basic building blocks or atoms which display regularities that can be described in the law statements of the most basic science. The basic atoms also combine to constitute larger structures which display characteristic regularities of their own. These can in turn be codified in the law statements of higher level sciences. But the higher level regularities do not emerge out of nothing. They can be explained as the consequences of the more basic patterns of behaviour of atoms. So the structure of the world and the structure of science can be seen as two isomorphic hierarchies of levels.

Now having graduated from an History and Philosophy of Science department I should note a couple of obvious and important caveats. First it is not clear that there is any such thing as the scientific method. A sad lesson of sustained work in the middle part of last century is that there are no plausible candidate necessary and sufficient analyses of scientific method. Second, the rise of scientific method was a contingent success driven as much by social as narrowly rational factors. Still, it does seem to me to be plausible that there is a kind of family resemblance. Scientific method has overlapping aspects but with some notions such as Mill's Method of Difference playing a key regulative role across a range of central cases.

If an instance in which the phenomenon under investigation occurs, and an instance in which it does not occur, have every circumstance in common save one, that one occurring only in the former; the circumstances in which alone the two instances differ, is the effect, or the cause, or an indispensable part of the cause, of the phenomenon. [Mill 1872: 452])

Against this background picture, the idea that there are fundamentally different research methods needs some explanation.

Three reasons why we might need different research methods

Despite qualms about Crotty’s pick and mix approach to science, I do think that there are some general arguments for differences, not merely at the level of practical tips, but with respect to accessing truth.

1: The aims of science can be general or particular.

One might study things or people either for their own sake or to generalise to other things or people. Wilhelm Windelband draws this distinction in his rectoral address of 1894.

In their quest for knowledge of reality, the empirical sciences either seek the general in the form of the law of nature or the particular in the form of the historically defined structure. On the one hand, they are concerned with the form which invariably remains constant. On the other hand, they are concerned with the unique, immanently defined content of the real event. The former disciplines are nomological sciences. The latter disciplines are sciences of process or sciences of the event. The nomological sciences are concerned with what is invariably the case. The sciences of process are concerned with what was once the case. If I may be permitted to introduce some new technical terms, scientific thought is nomothetic in the former case and idiographic in the latter case. Should we retain the customary expressions, then it can be said that the dichotomy at stake here concerns the distinction between the natural and the historical disciplines. However we must bear in mind that, in the methodological sense of this dichotomy, psychology falls unambiguously within the domain of the natural sciences. [Windelband 1980: 175-6]

Windelband himself attempts (unsuccessfully, I think) to flesh out the distinction between idiographic and nomothetic as distinct forms of understanding saying for example that idiographic sciences seeks structural forms or delineates particulars. But one might use the vocabulary to mark the distinction between the further aim of generalisation from research into particulars for their own sake. Such a distinction flags the further work that has to be done to avoid errors resulting from non-representative samples, errors from which the idiographic approach is safer. Of course, even research at the idiographic end is not safe from inductive risks since observational concepts carry future directed inferences.

2: Scientific method is itself the subject of science.

The biases worth avoiding are those that carry actual epistemic risk rather than merely possible risks. But since, as Hume teaches us and John Campbell has recently stressed, causal relations are contingent and independent of what seems natural to us. Hence it is a contingent matter what reliably indicates what. And hence we should expect epistemic differences in actual scientific practices depending on the subject matter.

3: The world is not an integrated set of properties.

The argument for a single research method above turned on the idea that nothing of epistemic significance is introduced in moving from the microphysical to the macro scale. But if one holds that mental phenomena are governed by the constitutive ideal of rationality, which ‘finds no echo in physical theory’, then – in accord with one of the competing views in the ‘methodenstreit’ – one should hold that different methods are necessary to chart meaningful from non-meaningful phenomena. This it seems to me is why social scientists are drawn to Crotty’s account of constructionism. They move from the idea that meaning is constructed in an encounter between subject and object to the mistaken conclusion that social scientist’s study of others’ meanings cannot itself aspire to truth.

So I do share with my tutees the view that there are interesting differences between research methods. Where I think I differ is the extent to which I also want some sort of self-conscious justification for articulating what the epistemic – rather than merely practical – differences comprise.