Observational Equivalence of Deterministic and Indeterministic Descriptions and the Role of Different Observations
Recently some results have been presented which show that certain kinds of deterministic descriptions and indeterministic descriptions are observationally equivalent (Werndl 2009a, 2011). These results prompt interesting philosophical questions, such as what exactly they show or whether the deterministic or indeterministic description is preferable. There is hardly any philosophical discussion about these questions, and this paper contributes to filling this gap. More specifically, first, I discuss the philosophical comments made by mathematicians about observational equivalence, in particular Ornstein and Weiss (1991). Their comments are vague, and I argue that, according to a reasonable interpretation, they are misguided. Second, the results on observational equivalence raise the question of whether the deterministic or indeterministic description is preferable relative to evidence. If the deterministic and indeterministic description are equally well supported by evidence, there is underdetermination. I criticise Winnie’s (1998) argument that, by appealing to different observations, one finds that the deterministic description is preferable. In particular, I clarify a confusion in this argument. Furthermore, I show that the argument delivers the desired conclusion relative to in principle possible observations, but that the argument fails relative to currently possible observations.
KeywordsRoulette Wheel Observation Level Outcome Space Philosophical Comment Fine Observation
I am indebted to Jeremy Butterfield for valuable suggestions. I am grateful for comments to Franz Huber, James Ladyman, Miklos Redei, Jos Uffink, two anonymous referees, and the audiences at the Oxford Philosophy of Physics Research Seminar, the Bristol Philosophy of Science Research Seminar, and the EPSA conference 2009. This research has been supported by a Junior Research Fellowship from the Queen’s College, Oxford University.
- Chernov, Nikolai, and Roberto Markarian. 2006. Chaotic billiards. Providence: American Mathematical Society.Google Scholar
- Werndl, Charlotte. 2011b. On choosing between deterministic and indeterministic models: Underdetermination and Indirect Evidence. Synthese. doi: 10.1007/S1122901199669.Google Scholar
- Winnie, J. 1998. Deterministic chaos and the nature of chance. In The cosmos of science – essays of exploration, eds. John Earman and John Norton, 299–324. Pittsburgh, PA: Pittsburgh University Press.Google Scholar