Biology Reference
In-Depth Information
toward the multitude of enzymes which break down the sugars and their prod-
ucts; in other words, we look at the metabolic pathways within the cell. However,
we look at these in toto. These are pathways for the processing of sugars within
a certain sort of cell with characteristic capacities. We might want to explain,
to take a very different behavior, a pain withdrawal reflex. To explain it, we
characterize the lower level components and their characteristic properties. One
set of nerves transmits a signal to the spinal chord from the periphery, which
in turn initiates a signal that causes muscular contraction. We can continue the
process, with an interest in, say signal transmission. At that point, we shift our
focus to the structure of nerves, the molecular mechanisms responsible for the
pulses down the axon, and the release of neurotransmitters. At each stage, we
focus on a characteristic set of components, and their characteristic behaviors,
with the goal of explaining the behavior of entities at a higher level.
We intend to explore the adequacy of these sorts of models of mechanistic
explanation, in light of the undeniably mechanistic accounts of the behavior of
unicellular organisms. There are a number of questions we will address, though
not in sequence. First, we ask whether the current models of mechanistic expla-
nation within philosophy are adequate for the broader range of scientific cases
they are intended to cover. This issue has already been raised in an evolutionary
context (Skipper & Millstein, 2005); we want to assess the question within the
context of molecular cell biology and systems biology. The specific models
offered by Glennan and by Machamer, Darden and Craver are not designed
for these sorts of cases but should cover them if they are adequate. So, one
concern is how generally these philosophical models apply. Second, and more
fundamentally, we ask whether mechanistic explanation actually fits a reductive
mode of explanation, or whether some properly mechanistic models are not
reductionist. We have argued (see Boogerd et al., 2005) that there are emer-
gent phenomena in cell biology that are also mechanistically explainable. The
key thought is that cell biology exhibits manifestly mechanistic explanations
of systemic behaviors; and these are properly emergent phenomena. We have
shown there is at least one scientifically and philosophically interesting sense
in which this is so. Here, we propose to further explore the thought that cell
biology exhibits emergent phenomena that are mechanistically explicable. If
this is so, then the context in which models of mechanistic explanation have
been developed may not exhibit the richness they deserve. The goal would be
to develop a more enhanced understanding of both mechanism and emergen-
tism, one which moves beyond the more standard mechanism/reductionism and
mechanism/eliminativism dichotomies.
Some theories appear to cross levels of organization or involve multiple levels
of explanation. These are the sorts of explanatory theories that are most inviting
to analysis in terms of mechanisms. Morton Beckner (1959) once called these
'interlevel' theories. In more recent discussions, the point has been repeated by,
