The concept of mechanism is analyzed in terms of entities and activities, organized such that they are productive of regular changes. Examples show how mechanisms work in neurobiology and molecular biology. Thinking in terms of mechanisms provides a new framework for addressing many traditional philosophical issues: causality, laws, explanation, reduction, and scientific change.

This article focuses on the assessment of mechanistic relations with specific attention to medicine, where mechanistic models are widely employed. I first survey recent contributions in the philosophical literature on mechanistic causation, and then take issue with Federica Russo and Jon Williamson’s thesis that two types of evidence, probabilistic and mechanistic, are at stake in the health sciences. I argue instead that a distinction should be drawn between previously acquired knowledge of mechanisms and yet-to-be-discovered knowledge of mechanisms and that both (...) probabilistic evidence and manipulation are essential with respect to newly discovered mechanisms. (shrink)

It has increasingly been recognised that units of biological classification cannot be identified with the units of evolution. After briefly defending the necessity of this distinction I argue, contrary to the prevailing orthodoxy, that species should be treated as the fundamental units of classification and not, therefore, as units of evolution. This perspective fits well with the increasing tendency to reject the search for a monistic basis of classification and embrace a pluralistic and pragmatic account of the species category. It (...) also provides a diagnosis of the paradoxical but popular idea that species are individuals: Species are not individuals, but the units of evolution are. (shrink)