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

Michael Silberstein
Humphreys suggests (1997) if there were widespread mereological emergence
or nonseparability then lower-level property instances would often “merge” in the
formation of higher-level properties such that they no longer exist as separate subvenient
entities. Widespread mereological emergence calls into question the very
picture of reality as divided into a “discrete hierarchy of levels”; rather it is
more likely that even if the ordering on the complexity of structures ranging from
those of elementary physics to those of astrophysics and neurophysiology is discrete,
the interactions between such structures will be so entangled that any separation into
levels will be quite arbitrary (Humphreys, 1997, p. 15).
Given widespread mereological emergence, the standard divisions and hierarchies
between phenomena that are considered fundamental and emergent, simple and
aggregate, kinematic and dynamic, and perhaps even what is considered physical,
biological and mental are redrawn and redefined. Such divisions will be dependent
on what question is being put to nature and what scale of phenomena is being
probed.
But on the face of it, one can embrace these alternative models of intertheoretic
reduction while maintaining that all apparent emergence is just a function
of ignorance. For example, Schaffner strongly suggests that nothing about such
tangled causal processes warrants any claims for either mereological emergence or
nomological emergence (such as vital or configurational forces). Rather, at worst,
such systems provide us with cases of predictive/explanatory emergence or representational/cognitive
emergence (Schaffner, 1998, pp. 242–5).
At present, both the emergentist and reductionist feel that, so far, things are
going their way. The emergentist points to failures of ontological and methodological
reductionism, and the reductionist points to successes. Regarding the
problematic cases of intertheoretic reduction, the perennial reductionist reply is
to claim that the future will bring success, just as in the past; emergentists likewise
feel that they will be redeemed by the future just as they are by the present.
This much is true I think, given the examples of both epistemological and ontological
emergence canvassed, there is no reason why the burden of proof should
continue to lie exclusively with emergentism. At this juncture, neither view is irrational
in light of the evidence and neither view is conclusive. Ultimately, emergentists
and reductionists are divided by a deeply held philosophical or aesthetic
preference that neither will relinquish easily. For example, many philosophers
persist in assuming that nomological and mereological reductionism are true in
spite of the actual state of unification within science and in spite of the fact that
fundamental physics itself might prove a counter-example to mereological supervenience.
Do the past successes of reductionism warrant those assumptions on
their part or is the assumption based largely on faith?
We know what questions need to be answered to resolve the debate between
emergentism and reductionism, but is it possible to ever answer them? How will we
know when we have answered them? It is no doubt prudent to remain agnostic
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