Robert Rosen

From Wikipedia, the free encyclopedia

Robert Rosen (June 27, 1934, Brooklyn, New York - December 28, 1998, Rochester, New York) was an American theoretical biologist and, later in life, a Professor of Biophysics at Dalhousie University until he retired. His main interest was developing a specific definition of complexity and an ensuing theoretical framework, now called "Rosennean Complexity". His main focus was the question: "what is life?" ("why are organisms alive?")

Another major theme in the work of Robert Rosen was the clarification of the notion of the scientific model. In fact, he maintained that modelling be the essence of science. His book Anticipatory Systems is mainly concerned with what he termed the modelling relationship.

In biology he is known by some for a class of relational cell models called (M,R)-systems that he devised. In these systems he tried to capture the minimal organization a material system would have to manifest to justify calling it a cell. However, Rosen's work proposes a methodology he terms "relational biology" (a term he borrows from Nicolas Rashevsky). Rosen’s "relational biology" maintains that organisms have a distinct quality called "organization" not captured by the language of differential equations but using category theory (a mathematical theory that deals with abstract structures, although his use of this theory is extremely elementary, employing little more than the definition of category and a few very simple properties of categories). This study, Rosen says, must be independent from which constitutes a living system.

He goes very far in this direction claiming that "when studying an organized material system, throw away the matter and keep the underlying organization". He makes this claim based on his view that up until he came into the picture, biologists were simply examining the material a biological system was made of, and simply ignoring the way it was organized. Relational biology concludes that: (a) "organization" is "that attribute of a natural system which codes into the form of an abstract block diagram” where "abstract block diagram" means a set of arrows and points, (b) physics is unable to capture life essence due the use of a mathematical formalism which is unable to express functions (a teleological notion introduced by Rosen as the behavioral difference between an organism with a "heterogonous state" and one without it).

Rosen also rejects some aspects of mainstream interpretations of biochemistry and biology. He objects the idea that the functional role of a protein can be investigated purely using the sequence of amino acids, due to intrinsic syntactic limitations of the habitual language of chemistry (graphs of atoms and molecules). Based on this thesis, Rosen says that is impossible to find either an algorithm that can calculate the three-dimensional conformation of a protein directly or the active site of it, although he made absolutely no attempt to formalize the problem in such a manner that would be required to prove such a claim. "If phenotype is chemistry, as mandated by the sequence hypotheses", he says, "that chemistry is not the familiar contemporary chemistry we find in books". In the case of biology, Rosen maintains that "Darwinian evolution" doesn’t provide any kind of causality or entailment, and without them, "turn evolution, and hence biology, into a collection of pure historical chronicles, like tables of random numbers, or stock exchange quotations". He maintains that the denial of "evolutionary entailments" represents an “excuse itself from science through its absolute denial”. The proposed solution for this problem is embracing entailment in evolution, citing the works of Ernst Haeckel and his idea of “ontogeny recapitulates phylogeny”, René Thom’s Catastrophe Theory and D’Arcy Thompson’s On Growth and Form.

Questions about Rosen's arguments were raised in a paper authored by Christopher Landauer and Kirstie L. Bellman which claims that some of the mathematical formulations used by Rosen are problematic. They also claim that the idea that it is possible to establish a correspondence relation between languages and ideal or abstract entities different but related to physical objects has been repudiated in a broad sense from disciplines like linguistics and philosophy of language.

All quotes are from Life Itself: A Comprehensive Inquiry into the Nature, Origin, and Fabrication of Life.

See also: autopoiesis

[edit] Bibliography

Selected bibliography
- Dynamical Systems Theory in Biology (1970) Wiley Interscience, New York
- Optimality Principles (out of print) (Being republished, Rosen Enterprises)
- Fundamentals of Measurement and Representation of Natural Systems (1978) Elsevier Science Ltd, ISBN 0-444-00261-8 (out of print) (republished 2003, Rosen Enterprises)
- Anticipatory Systems: Philosophical, Mathematical and Methodological Foundations (1985) Pergamon Press, ISBN 0-08-031158-X (out of print) (republished 2003, Rosen Enterprises)
- Life Itself: A Comprehensive Inquiry into the Nature, Origin, and Fabrication of Life (1991) Columbia University Press, ISBN 0-231-07564-2
Published posthumously
- Essays on Life Itself (2000) Columbia University Press, ISBN 0-231-10511-8
- Rosennean Complexity (2003) Rosen Enterprises
- The Limits of the Limits Of Science (2003) Rosen Enterprises