The Propensity Interpretation of Fitness

  title={The Propensity Interpretation of Fitness},
  author={Susan K. Mills and John H. Beatty},
  journal={Philosophy of Science},
  pages={263 - 286}
The concept of "fitness" is a notion of central importance to evolutionary theory. Yet the interpretation of this concept and its role in explanations of evolutionary phenomena have remained obscure. We provide a propensity interpretation of fitness, which we argue captures the intended reference of this term as it is used by evolutionary theorists. Using the propensity interpretation of fitness, we provide a Hempelian reconstruction of explanations of evolutionary phenomena, and we show why… 

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