The Blackwell Guide to the Philosophy of Science - The Department ...

Reduction, Emergence and Explanation
1 Property/kind cross-theoretic (ontological) identities are to be determined
solely by formal criteria such as successful intertheoretic reduction, e.g.,
smooth intertheoretic reduction is both necessary and sufficient for crosstheoretic
identity.
2 Realism, scientific theories are more than mere “computational devices.”
and/or one or more epistemological assumptions:
1 Philosophy of science is prescriptive rather than descriptive, e.g., philosophy
of science should seek a grand, universal account of intertheoretic
reduction.
2 Scientific theories are axiomatic systems.
3 Reduction = logical deduction, or at least deduction of a structure specified
within the vocabulary and framework of the reduced theory or some corrected
version of it.
4 Necessity of bridge laws or some other equally strong cross-theoretic connecting
principles to establish synthetic identities.
5 Symbolic logic is the appropriate formalism for constructing scientific theories.
6 Scientific theories are linguistic entities.
7 Hardcore explanatory unification. Reduction is proof of displacement (in principle)
showing that the more comprehensive reducing theory contains explanatory
and predictive resources equaling or exceeding those of the reduced
theory.
8 Intertheoretic reductions are an all or nothing synchronic affair as in the case
of “microreductions” (Oppenheim and Putnam, 1958; Causey, 1977): the
lower-level theory and its ontology reduce the higher-level theory and its
ontology. Ontological levels are mapped one-to-one onto levels of theory
which are mapped one-to-one onto fields of science.
9 The architecture of science is a layered edifice of analytical levels (Wimsatt,
1976).
Alternatives to the Nagel (1961) model are deemed more or less radical (by
comparison) depending on which of the preceding tenets are abandoned. On the
more conservative side, many alternative accounts of intertheoretic reduction
merely modify (3) by moving to logico-mathematical deduction, but reject (4).
For example, the requirement of bridge laws gets replaced by notions such as:
“analog relation” – an ordered pair of terms from each theory (Hooker, 1981;
Bickle, 1998), “complex mimicry” (Paul Churchland, 1989) or “equipotent
image” (Patricia Churchland, 1986), to name a few. Many of these comparatively
conservative accounts also reject (8), preferring to talk about a range of reductions,
from replacement on one end of the continuum to identity on the other.
More radical alternatives to the Nagel models are as follows.
87