This
book shows that there are at least two ways in which the philosophy of biology
contributes to the philosophy of science. One is the philosophical reflection
on special questions posed in biology (those undertaken here all arise from an
evolutionary perspective). The other is the discussion of general issues of the
philosophy of science from the point of view of biology, so that its specific
characteristics may define and configure the topics to be considered. This
second line allows one to take into account problems arising beyond the scope
of those found in physics, the "model science" of the classical
approach. The book at hand presents developments in both of these lines, by
considering the notion of complexity and defending pluralism on its behalf.

The
main thesis of the book is that the complexity of biological systems shapes the
form of the scientific explanations adequate for them and justifies pluralism
("Pluralism can simply reflect complexity" p. 3). This is a defense
of pluralism that does not celebrate diversity just for the sake of it (in fact
the author does her best to separate her position from other
"anything-goes" appeals of pluralism), but argues from metaphysical
(nature of complex systems and their processes) and epistemological (limitation
of our explanations) grounds. In Part I various very specific aspects of this
complexity are presented, whereas Part II explores the nature of scientific
(more specifically biological) laws in the light of that complexity and finds a
need for a different way (not normative but pragmatic) of characterizing them
which leads to a plea for pluralism.

How
do the essays in the book show or contribute to this thesis? In the first part
three forms of complexity are distinguished: constitutive complexity, dynamic
complexity and evolved diversity. Compositionally, complex living systems are
constituted by non-randomly structured parts; examples are the multicellular organism, an ecosystem or an insect colony.
Dynamically, they are the location for multiple, interacting causes.
Evolutionarily, they display a variety of historically contingent, adaptive
responses to environmental challenges. Nevertheless, Part I is
not a purposefully written exposition of these three aspects of complexity, but
a collection of (already and separately published) essays assembled under a new
general overview based on the mentioned guidelines.

Constitutive
complexity, emerging from how parts are arranged to form complex structures, is
illustrated with an essay on a specific point (chapter 2): how does the
organization of insect societies resemble that of a multicellular
organism? The essay looks at the notion of superorganism,
used by different authors throughout the XXth century
and recently rescued to argue in favor pluralistic conceptions of the level at
which selection acts. Although the author accords with the need for pluralism,
she finds the superorganism metaphor misleading,
because it is based on a parallel with a narrow definition of an organism (weismanian model) that obscures the fact that there exist
very different forms of insect colony organization (as there are different
forms of multicellular organizations), and because
there are better forms to argue for a plurality of levels in terms of
hierarchical complex systems.

Dynamic
complexity is pictured through work on self-organizing models of Kaufmann´s NK type to explain different dynamical
properties of insect organizations (chapter 3). The aim is to explore
self-organizing properties of complex systems instead of adaptationist
views in which all the constituents evolve atomistically
through natural selection. The example of social insects is recurrent in
several of the essays, some of them coauthored with Robert Page.

Chapter
4 is nominally devoted to evolved diversity, but is formed by some essays on
central and debated topics on evolutionary biology such as the units of
selection (this part contains a very useful analysis of how the solution to the
problem requires to conceive evolution by natural selection as a two step
process, and the consequences of reducing it to either a problem of replicators or of interactors),
sociobiology (on whether behavioral traits can evolve by natural selection) and
biological function (with a defense of an etiological notion in contrast with
dispositional accounts). The three essays include insightful views of previous
positions and well documented examples.

All
in all, the three chapters of Part I present a certain bias towards
evolutionary accounts of the nature of the biological and this has consequences
on the notion of complexity considered by the author. More encompassing views
are possible and necessary.

Part
II of the book addresses the questions of biological laws and pluralism. In
what respects the first problem the author first provides a good review of the
issue of biological laws as discussed in the middle 90´s (chapter 5). According
to the ECT (evolutionary contingency thesis), the laws that apply to living
systems are either physical, chemical and mathematical or distinctively
biological in that they describe a contingent outcome of evolution. Although
the author accepts this contingency, its consequences must be tempered with a
careful attention of the necessity shown by other kinds of laws that are not
biological. The standard approach to the notion of scientific law admits that
natural laws are contingent (their necessity is not logical), but they are
understood according to a notion of necessity that mirrors logical necessity
too closely. The author’s analysis of the different conditions of the universe
that account for the different levels of necessity that support different kinds
of laws is very interesting. Her conclusion is that most studies of the notion
of law in the philosophy of science have been developed under a "normative"
conception related to the reductionist perspective favored by the ideal of the
unity of science. In contrast, she defends a pragmatic approach to laws that
provides a more adequate representational framework because the question of
contingency may be related to that of how generalizations of various types
function in different inferences to satisfy the pragmatic goals of science.

In
the last chapter the author defends her version of pluralism, one whose
challenge is to explain "how can a diverse, well confirmed, but
irreducible set of theories be used collectively to achieve a more complete
understanding than any of the theories taken in isolation?" (p. 115). The
author considers the reasons for reductionism and defends an alternative based
on the integration of compatible, not competitive, explanations.

Because
the book is based on a collection of independently published articles, its
appeal is in the local and detailed arguments and thoughts (which are fresh,
well written and suggestive), whereas the global thread seems to be
superimposed to them and sometimes underdeveloped. Readers interested in
general philosophy of science and/or specific topics of the philosophy of
biology will enjoy the book, including students, whereas those expecting an elaborate
exposition of complexity may feel disappointed.

© 2004 Arantza Etxeberria

Arantza Etxeberria, Ph.D., Dept. of Logic and Philosophy
of Science, University of the Basque Country, Spain

Categories: Philosophical