In this talk Professor Williamson will provide an introduction to Evidential Pluralism, a new approach to causal inference that has emerged from recent philosophical research on mechanisms in science. According to Evidential Pluralism, in order to establish that A is a cause of B one needs to establish both that A is correlated with B (conditional on potential confounders) and that there is a mechanism from A to B that can account for that correlation; so, in order to assess whether A is a cause of B one needs to scrutinise mechanistic studies alongside studies that measure the extent to which A and B are correlated. Evidential Pluralism motivates a new approach to evidence-based medicine, called EBM+, and a new approach to evidence-based policy assessment, EBP+. It also provides a general framework for integrating quantitative and qualitative evidence, and for integrating social and biomedical mechanisms in the health sciences. Dr. Williamson will discuss some of these developments and show how Evidential Pluralism can explain the role and limits of specific methods for causal enquiry such as randomised controlled trials, graphical causal modelling and theory-based evaluation.

NIH Videocast: https://videocast.nih.gov/watch=52416