Original paper in Philosophy of Biology

European Journal for Philosophy of Science

, Volume 2, Issue 3, pp 337-353

First online:

Filling in the mechanistic details: two-variable experiments as tests for constitutive relevance

  • Tudor M. BaetuAffiliated withDepartment of Philosophy, University of Maryland Email author 

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This paper provides an account of the experimental conditions required for establishing whether correlating or causally relevant factors are constitutive components of a mechanism connecting input (start) and output (finish) conditions. I argue that two-variable experiments, where both the initial conditions and a component postulated by the mechanism are simultaneously manipulated on an independent basis, are usually required in order to differentiate between correlating or causally relevant factors and constitutively relevant ones. Based on a typical research project molecular biology, a flowchart model detailing typical stages in the formulation and testing of hypotheses about mechanistic components is also developed.


Molecular biology Experimentation Mechanistic explanation Causal relevance