Explanation, emergence and causality. A comment on Crane

Tim Crane’s paper “Cosmic Hermeneutics vs. Emergence: the Challenge of the Explanatory Gap”, is a valuable contribution to our understanding of the relation between physicalism, explanation, and emergentism, and offers a new reading of the significance of the ‘explanatory gap’ (Levine 1983)—a reading which amounts to a strong attack on non-reductive physicalism. In my paper I argue that if we look at the relation between physicalism and reductionism from the vantage point of reduction Crane’s analysis is rather persuasive. However, if we switch from reduction to causality, its conclusions appear to be more doubtful. I shall proceed in the following way: first I focus on a few points in Crane’s overall strategy, and in particular on (1) the thesis that the supervenience of the mental cannot be accepted as a ‘brute fact’ by a physicalist; (2) his reading of the idea that emergent properties are ‘not added from outside’. Then I explore the possibility of the existence of an interesting form of non-reductive physicalism. To do this, I shift from ‘novelty and explanation’ to ‘novelty and causality’ as key features of emergent properties.