Philosophical Studies

, Volume 143, Issue 1, pp 127–136 | Cite as

Evidence-based policy: what’s to be done about relevance?

For the 2008 Oberlin Philosophy Colloquium
  • Nancy Cartwright


How can philosophy of science be of more practical use? One thing we can do is provide practicable advice about how to determine when one empirical claim is relevant to the truth of another; i.e., about evidential relevance. This matters especially for evidence-based policy, where advice is thin—and misleading—about how to tell what counts as evidence for policy effectiveness. This paper argues that good efficacy results (as in randomized controlled trials), which are all the rage now, are only a very small part of the story. To tell what facts are relevant for judging policy effectiveness, we need to construct causal scenarios about will happen when the policy is implemented.


Evidence Evidence-based policy Evidential relevance Randomized controlled trials Efficacy Effectiveness 


  1. Achinstein, P. (1983). The nature of explanation. Oxford: Oxford University Press.Google Scholar
  2. Borhnstedt, G. W., & Stecher, B. M. (Eds.). (2002). What we have learned about class size reduction in California. CA, USA: California Department of Education.Google Scholar
  3. Cartwright, N. (1989). Nature’s capacities and their measurement. Oxford: Oxford University Press.Google Scholar
  4. Cartwright, N. (2007). Hunting causes and using them: Approaches in philosophy and economics. Cambridge: Cambridge University Press.Google Scholar
  5. Cartwright, N. (2009) What is this thing called efficacy. In C. Mantzavinos (Ed.), Philosophy of the social sciences. Philosophical theory and scientific practice. Cambridge: Cambridge University Press (to appear).Google Scholar
  6. Reiss, J. (2005). Causal instrumental variables and interventions. Philosophy of Science, 72(5), 964–976.CrossRefGoogle Scholar
  7. Roush, S. (2005). Tracking truth: Knowledge, evidence, and science. Oxford: Oxford University Press.CrossRefGoogle Scholar
  8. U.S. Department of Education Institute of Education Sciences National Center for Education Evaluation and Regional Assistance (2003). Identifying and implementing educational practices supported by rigorous evidence: A user friendly guide.

Copyright information

© Springer Science+Business Media B.V. 2008

Authors and Affiliations

  1. 1.CPNSS, LSELondonUK

Personalised recommendations