Understanding Mechanisms in the Health Sciences

As largely recognised, mechanical models are widely employed in the biomedical sciences. The notion of mechanism is ubiquitously used to refer to mechanisms of diseases, for instance mechanisms of heart failure, of cardiovascular diseases, of migraine, of obesity, of diabetes’ complications, of post-traumatic stress disorders; to refer to drugs and treatments, for instance deep brain stimulation and percutaneous coronaric intervention; to indicate mechanisms by which socio-economic status influences health. Mechanical terms are even used to indicate pathologies whose functioning is still rather mysterious: “mechanism” can be a label put on what is still largely unknown, and yet believed to be decomposable into a number of causal relations. In many medical cases the “mechanism” is the final target of the research, something which is still largely to be investigated, such as the functioning of peripartum cardiomyopathy (Sliwa et al. 2006), of Paget’s disease (Whyte 2006), mechanisms linking infertility and congenital malformation (Zhue et al. 2006). At the same time, mechanicism has been finding increasing consent as an approach to causation in the contemporary philosophical debate, with a number of different mechanical views being developed since the middle Eighties. This contribution focuses on a few problematic points in the current debate on mechanisms and mechanical causation, with a specific attention to medicine. Referring to both some recent philosophical literature on causation in the health sciences and to a specific medical case-study, it is argued that how one gets from detecting correlations to hypothesizing that a causal, productive mechanism is in place asks for a deeper enquiry. Though crucial for the causation debate in general, such an issue is tackled here with respect to medicine due to the large interest this field is showing for mechanical views.