Foundations of Biophilosophy

  • Martin Mahner &
  • Mario Bunge
Springer: 1997. Pp. 423 $54, £36.50

The logical empiricist consensus that existed in the philosophy of science until the 1960s held that the ideal statement of a scientific theory would be a formal axiom system of the kind found in mathematics. The biologist J. H. Woodger is remembered for his attempts to make biology live up to this ideal. For reasons too complex and varied to explore here, few philosophers of science now try to make scientific theories axiomatic.

It is therefore surprising to find the biologist Martin Mahner and the philosopher Mario Bunge formulating their general account of biology using the logical apparatus of predicate calculus and set theory, complete with axioms, definitions and corollaries. Their aim appears twofold: to ensure consistency between their views on diverse topics and to ensure that their biological views are as tightly constrained as possible by the metaphysics that occupies the first third of their book. This introductory section takes a stand on most of the basic questions of metaphysics and epistemology. Topics covered include basic ontology (the nature of events, properties and things), the interpretation of the probability calculus and the nature of truth and evidence. Philosophers will be frustrated at the speed with which Mahner and Bunge dismiss alternative positions, and biologists should beware of taking their often strongly stated views to represent a philosophical consensus. However, it is hard to see how these problems could be avoided without turning this into a book on metaphysics and epistemology, rather than biology. Bunge has argued at length for his views in many other works.

Perhaps the biggest surprise is that there is no discussion of the reduction of Mendelian to molecular genetics. This is the topic in the philosophy of biology most influenced by the axiomatic method. The original idea of ‘theory reduction’ was that the axioms of one, formalized theory should be derived logically from those of another, thus showing that nothing is lost when the former is replaced by the latter. This omission is more surprising because the coverage of the book is otherwise excellent.

There are two further surprises in Mahner and Bunge's biophilosophy. First, they reject ‘population thinking’: evolution is not about ensembles of individuals but about types of organism. They argue that these types, which include species, are in some sense ‘natural kinds’. They strongly reject the consensus view, deriving from David L. Hull and Michael Ghiselin, that taxa are ontologically akin to individual objects such as nations rather than to natural kinds such as gold. The second surprise is the authors' radical approach to developmental biology: development is not guided by a genetic program. Instead, Mahner and Bunge call for a synthesis between the ‘structuralist’ approach to development, which seeks emergent laws of complex biological systems, and the ‘constructionist’ view that the control of development cannot be localized in one material cause.

Having adopted this radical perspective, Mahner and Bunge attack existing structuralists and constructionists in a manner worthy of Trotskyite splinter politics. The structuralism of Brian Goodwin must be rescued from “holism, (crypto)idealism and subjectivism” by the adoption of Mahner and Bunge's metaphysical scheme. My own advocacy of constructionism with the biologist Russell Gray “must be judged as an utter failure” because of a “severely flawed ontology” which I share with A. N. Whitehead and Hull.

Mahner and Bunge convict most existing biological theorists of basic metaphysical errors, something they hope to avoid through their formal, axiomatic method. For example, Theodosius Dobzhansky characterized evolution as change in the genetic composition of populations owing to “altered interactions with their environment”. The authors may be right that it is strictly organisms rather than populations that interact with the environment, but I remain unconvinced that Dobzhansky's slip shows “how easily habits of speech may obfuscate clarity and proper theorising”.

This tendency to over-diagnose fundamental metaphysical confusions and to deduce absurd apparent consequences reduces the usefulness of this book as a text for students, despite its admirably wide coverage of the subject. The axiomatic framework and use of logical symbolism will also be unattractive to students, especially those in biology.