Biology Reference
In-Depth Information
6. EIGHT IMPLICATIONS OF THE TWO EXEMPLARS FOR
SYSTEMS BIOLOGY
I can think of eight implications of the above discussion for philosophical issues
in systems biology; other may see additional implications.
(1) In biology, the roles that general theories have in physics (as explainers,
organizers of domains of inquiry, and experimental fertility) is carried out
by a series of prototypes (think of these as models or as mechanisms) which
are causal-temporal multilevel systems and are analogically related to other
prototypes.
(2) Those prototypes may be formulated in quantitative terms, though typically
they are not, and in their quantitative variants these may even appear in
a mathematical form that is very much like that found in general phys-
ical theories, such as in Maxwell's equations or the axioms of quantum
mechanics. But the equations describing the prototypes are not universal
ones, rather they are tied closely to the specific organisms on which they
are based, though they can be extended. Such equations are also typically
approximations rather than exact equations.
(3) Biological prototypes are applied, in the sense of being used as explain-
ers or as extending the application to another biological organism, more
by analogical reasoning than by determining the mathematically expressed
initial conditions (or boundary conditions) and proceeding deductively, by
inserting those conditions into equations to particularize and thus apply the
general system.
(4) Biological prototypes need not be only gene based. The H and H and the
F and L exemplars are not gene based, but do their work well, though the
H and H model is much more generalizable, for reasons speculated on in the
text above. Genetic information may assist in specifying highly particular
variants of mechanisms, such as receptors, and even in identifying classes
of control mechanisms, but a genetic dimension is not always needed.
(5) Biological prototypes incorporate critical structural information. This struc-
tural information is 'biological' in nature, as opposed to simple physical and
chemical structural information. In an important sense, the explanation for
biological structure requires an implicit appeal to billions of years of evolu-
tion, but working biologists need to assume that structure is an 'emergent'
given in investigating any biological system, and need to characterize the
prototype being studied at the appropriate levels with such structure assumed.
We saw this in the H and H example in terms of accepting a cable model
for the giant squid axon, constructed in part out of a structured membrane
permitting sodium and potassium ion passage. In the F and L
C. elegans
