Annals of the History and Philosophy of Biology

Holism, Coherence and the Dispositional Concept of Functions
glucose consumption? Can't we just choose as the overall systems capacity whatever we
find interesting, thus making functions interest-relative? Can functions be seen as natural
properties on such an account?
For Cummins himself, these are simply not desiderata of functional analysis. He fully
accepts the consequence that, on his account, the overall systems capacity is ours to
choose, and it does not appear to be among his goals to naturalize functions (see
McLaughlin 2001, pp. 119-124). However, it seems to be a goal of biological science to
identify the natural functions of some organ and structure. A biologist who says "I happen
to be interested in blood circulation, therefore I see the heart's function in pumping
blood" would appear rather unusual. Biologists want to discover what the function of
some biological structure is, and they want their functional explanations to be made true
by natural facts. Thus, Cummins' desiderata for functional analysis and those of a modern
biologist appear to be different. 1
This raises the question of whether there is an analysis that renders functions natural
properties of some part of a system. One possibility, of course, is to endorse an etiological
account of functions (also known as "proper" functions; see Millikan 1984). The usual
versions of this account tie functions to natural selection. The function of a thing or
structure is the activity for which it was selected in the organism's evolutionary history.
However, there are some well-known difficulties with this account. First, it will not admit
anything as a function that has just arisen anew (for example, by spontaneous mutation)
without having experienced the influence of natural selection yet. Second, biologists
sometimes attribute functions without knowing the evolutionary past of some part or
structure. Of course, one could argue that this is so much the worse for the standard
usage of the term in biology (if there is a single standard usage, which is questionable).
But to make sense of scientific practice it is necessary to give an account (or several accounts,
should there be different concepts of functions used in biology) that picks out
those things as functions that biologists ascribe functions to. There is an alternative version
of the etiological account that has recently been developed by Peter McLaughlin
(2001) that might be adequate to this task. I shall briefly discuss this account in Section 5.
Now, I will discuss an additional constraint to the dispositional account that could also
make functions natural properties.
3. Introducing a Coherence Constraint
As we have seen, it is an intended consequence of Cummins's account that the overall
systems capacity in relation to which some capacities emerge as functions can be chosen
freely by the investigator. Let us consider the example of the heart again in order to examine
the options. Cummins requires that, in order to ascribe a function to the heart, we
need to pick a systems capacity and show how some capacity of a part contributes to the
exercise of this capacity of the whole. For all we know, the heart has the capacity to
pump blood, which contributes to the circulatory system's capacity to deliver oxygen and
1 Cummins' main interest is not in biology, but in psychology and the philosophy of mind (see Cummins
1983). It is beyond the scope of this paper to assess the adequacy of his account in these areas.
Annals of the History and Philosophy of Biology, Vol. 10 (2005)
191