Online research in philosophy

Explanatory pluralism is the view that the best form and level of explanation depends on the kind of question one seeks to answer by the explanation, and that in order to answer all questions in the best way possible, we need more than one form and level of explanation. In the first part of this article, we argue that explanatory pluralism holds for the medical sciences, at least in theory. However, in the second part of the article we show that medical research and practice is actually not fully and truly explanatory pluralist yet. Although the literature demonstrates a slowly growing interest in non-reductive explanations in medicine, the dominant approach in medicine is still methodologically reductionist. This implies that non-reductive explanations often do not get the attention they deserve. We argue that the field of medicine could benefit greatly by reconsidering its reductive tendencies and becoming fully and truly explanatory pluralist. Nonetheless, trying to achieve the right balance in the search for and application of reductive and non-reductive explanations will in any case be a difficult exercise.

Explanatory problems in the philosophy of neuroscience are not well captured by the division between the radical and the trivial neuron doctrines. The actual problem is, instead, whether mechanistic biological explanations across different levels of description can be extended to account for psychological phenomena. According to cognitive neuroscience, some neural levels of description at least are essential for the explanation of psychological phenomena, whereas, in traditional cognitive science, psychological explanations are completely independent of the neural levels of description. The challenge for cognitive neuroscience is to discover the levels of description appropriate for the neural explanation of psychological phenomena.

Some social scientists and philosophers (e.g., James Coleman and Jon Elster) claim that all social facts are best explained by means of a micro-explanation. They defend a micro-reductionism in the social sciences: to explain is to provide a mechanism on the individual level. The first aim of this paper is to challenge this view and defend the view that it has to be substituted for an explanatory pluralism with two components: (1) structural explanations of P-, O- and T-contrasts between social facts are more efficient than the competing micro-explanations; and (2) whether a plain social fact (as opposed to a contrast) is best explained in a micro-explanation or a structural explanation depends on the explanatory interest. The second aim of the paper is to show how this explanatory pluralism is compatible with ontological individualism. This paper is motivated by our conviction that explanatory pluralism as defended by Frank Jackson and Philip Pettit is on the right track, but must be further elaborated. We want to supplement their contribution, by (1) introducing the difference between explanations of facts and explanations of contrasts; (2) giving examples from the social sciences, instead of mainly from the natural sciences or common sense knowledge; and (3) emphasizing the pragmatic relevance of explanations on different levels –social, psychological, biological, etc. – which is insufficiently done by Jackson and Pettit.

The connection between idealizations, competence and multi-level explanations in cognitive psychology is discussed, in response to Patterson's ([1998]) reply to Franks ([1995]). I argue that idealizations are inherent in competence explanations and as a result, such explanations cannot be formulated in the multi-level terms widely used in the cognitive sciences. Patterson's argument was that neither competence nor performance involve idealizations, and, since they are separate 'systems', it is inappropriate to apply a single multi-level explanation to them. I suggest that there is evidence that, although competence and performance are very often explicated in terms of levels of description, both none the less involve idealizations. However, I also suggest that Patterson's argument rests on confounding the demarcation of cognitive explanations with the demarcation of cognitive systems. Hence, even if competence and performance are different levels of a single system, questions concerning idealizations still arise when they are combined in an explanation.

The preference for `reductive explanations', i.e., explanations of the behaviour of a system at one `basic' level of sub-systems, seems to be related, at least in the physical sciences, to the success of a formal technique –- perturbation theory –- for extracting insight into the workings of a system from a supposedly exact but intractable mathematical description of the system. This preference for a style of explanation, however, can be justified only in the case of `regular' perturbation problems in which the zeroth-order term in the perturbation expansion (characterizing the `basic' level) is the uniform limit of the exact solution as the perturbation parameter goes to zero. For the much more frequent case of `singular' perturbation problems, various techniques have been developed which all introduce a hierarchy of levels or scales into the solutions. These levels describe processes or sub-systems operating simultaneously at different time or spatial scales. No single level, no reductive explanation in the above sense will provide an adequate explanation of the system behaviour. Explanations involving multiple levels should be recognized as far more common even in supposedly reductionist disciplines like physics.

This paper explores the explanatory adequacy of lower-level theories when their higher-level counterparts are irreducible. If some state or entity described by a high-level theory supervenes upon and is realized in events, entities, etc. described by the relevant lower-level theory, does the latter fully explain the higher-level event even if the higher-level theory is irreducible? While the autonomy of the special sciences and the success of various eliminativist programs depends in large part on how we answer this question, neither the affirmative or negative answer has been defended in detail. I argue, contra Putnam and others, that certain facts about causation and explanation show that such lower-level theories do explain. I also argue, however, that there may be important questions about counterfactuals and laws that such explanations cannot answer, thereby showing their partial inadequacy. I defend the latter claim against criticisms based on eliminativism about higher-level explanations and sketch a number of empirical conditions that lower-level explanations would have to meet to fully explain higher-level events.

I discuss arguments about the relationship between different “levels” of explanation in the light of examples involving multi-scale analysis. I focus on arguments about causal competition between properties at different levels, such as Jaegwon Kim’s “supervenience argument.” A central feature of Kim’s argument is that higher-level properties can in general be identified with “micro-based” properties. I argue that explanations from multi-scale analysis give examples of explanations that are problematic for accounts such as Kim’s. I argue that these difficulties suggest that some standard assumptions about causal competition need to be revised.

Until recently, the notions of function and multiple realization were supposed to save the autonomy of psychological explanations. Furthermore, the concept of supervenience presumably allows both dependence of mind on brain and non-reducibility of mind to brain, reconciling materialism with an independent explanatory role for mental and functional concepts and explanations. Eliminativism is often seen as the main or only alternative to such autonomy. It gladly accepts abandoning or thoroughly reconstructing the psychological level, and considers reduction if successful as equivalent with elimination. In comparison with the philosophy of mind, the philosophy of biology has developed more subtle and complex ideas about functions, laws, and reductive explanation than the stark dichotomy of autonomy or elimination. It has been argued that biology is a patchwork of local laws, each with different explanatory interests and more or less limited scope. This points to a pluralistic, domain-specific and multi-level view of explanations in biology. Explanatory pluralism has been proposed as an alternative to eliminativism on the one hand and methodological dualism on the other hand. It holds that theories at different levels of description, like psychology and neuroscience, can co-evolve, and mutually influence each other, without the higher-level theory being replaced by, or reduced to, the lower-level one. Such ideas seem to tally with the pluralistic character of biological explanation. In biological psychology, explanatory pluralism would lead us to expect many local and non-reductive interactions between biological, neurophysiological, psychological and evolutionary explanations of mind and behavior. This idea is illustrated by an example from behavioral genetics, where genetics, physiology and psychology constitute distinct but interrelated levels of explanation. Accounting for such a complex patchwork of related explanations seems to require a more sophisticated and precise way of looking at levels than the existing ideas on (reductive and non-reductive) explanation in the philosophy of mind.

I compare two competing positions regarding relations between sciences: reductionism and explanatory pluralism. I argue that reductionism is not warranted by evidence from scientific practice, but on the other hand, it is important to emphasize certain fundamental differences between generalizations and explanations of different levels. To show this, I take up Woodward’s notion of invariance, arguing that lower-level generalizations generally have a higher degree of invariance under interventions than higher-level generalizations. Since degree of invariance tracks degree of explanatory depth, lower-level explanations are in this sense better than higher-level ones.

Instances of explanatory reduction are often advocated on metaphysical grounds; given that the only real things in the world are subatomic particles and their interaction, we have to try to explain everything in terms of the laws of physics. In this paper, we show that explanatory reduction cannot be defended on metaphysical grounds. Nevertheless, indispensability arguments for reductive explanations can be developed, taking into account actual scientific practice and the role of epistemic interests. Reductive explanations might be indispensable to address some epistemic interest answering a specific explanation-seeking question in the most accurate, adequate and efficient way. Just like explanatory pluralists often advocate the indispensability of higher levels of explanation pointing at the pragmatic value of the explanatory information obtained on these higher levels, we argue that explanatory reduction—traditionally understood as the contender of pluralism—can be defended in a similar way. The pragmatic value reductionist, lower level explanations might have in the biomedical sciences and the social sciences is illustrated by some case studies.