1. A Pragmatic Theory of Scientific Explanation Raoul Gervais

2. Basic Idea Construct a theory of scientific explanation ‘bottom up’; i.e. by starting from an analysis of scientific practice Consider examples from a wide range of disciplines

3. Basic Idea Explanations as answers to why-questions – Why-questions originate in different epistemic interests – Epistemic interests influence the structure of explanations – Epistemic interests provide a context in which to analyze explanatory power

4. Specific questions Which epistemic interests can lead to explanation requests and how do they relate to each other? What does this tell us about the possible structures of scientific explanations? What does this tell us about the criteria for assessing explanatory power?

5. Goals To answer these questions systematically for a wide range of disciplines See what these answers have in common Arrive at a scientifically informed theory of explanation

6. My contribution To answer these questions for: – Psychology – Biology Relating these answers back to the overall project Example of current research

7. Explaining depression What kind of epistemic interests might one have concerning depression? – Basic understanding – Description – Prediction – Prevention – Therapeutic interest

8. Explaining depression Look at neuroticism: like depression, a psychologically defined state: irritability, anger, anxiety etc. Is statistically identified as cause of depression: depression explained as an effect of neuroticism, which is fine if our epistemic interest is prediction or description

9. Explaining depression Preventive/therapeutic – Psychotherapy – Neurology

10. The problem of interlevel explanation Within this particular account, interlevel explanation poses a particular problem: – So then, if neuroscientific explanations are going to compete with psychological ones with respect to a set of questions, the contrast class for the two domains questions [sic] would have to correspond. But because psychology and neuroscience operate in such different academic environments, prima facie it is doubtful that the contrast classes do correspond. At least, we would need an argument that the contrast classes are importantly similar (Hardcastle 1998, p. 16-17).

11. The erotetic account Obvious solution: translating vocabularies – However, the example of classical reductionism acts as a deterrent – Proposal: Pragmatic factors suggest on what level to look First, hypothetical interlevel identities are assumed Next, the identity is confirmed by experiments/manipulation So, the second and third requirments are met: pluralism regarding levels, but what level is chosen is determined by pragmatic factors

12. The depression/neuroticism example The pragmatic factors suggest where to look: in the case of neuroticism, over six decades of experimentation has established link to serotonin levels At first, this was a mere hypothesis (Wooley and Shaw) But has since been confirmed by experimentation and a successful track record (pharmacology)

13. The depression/neuroticism example A quote from Woolley & Shaw says it in a nutshell: – …these pharmacological findings indicate that serotonin has an important role to play in mental processes and that the suppression of its action results in a mental disorder. If now a deficiency of serotonin in the central nervous system were to result from metabolic rather than from pharmacologically induced disturbances, these same mental aberrations would be expected to become manifest. […] If the hypothesis about serotonin deficiency is accepted, then the obvious thing to do is to treat patients having appropriate mental disorders with serotonin (Woolley & Shaw 1954 p. 230).