duminică, 3 ianuarie 2010

A Much Needed Approach

It has become fashionable to dismiss evolutionary thinking as "biological reductionism". [...] The underlying premise is that cultural anthropology and sociology deal with complex levels of organization that exhibit emergent properties, and the concepts appropriate for description and analysis at lower levels are inadequate when applied to the social sciences. Attributing behavior to genes is therefore seen as an inappropriate effort at reductionism. This view contains a kernel of truth but is frequently incorrect in its application. We have considered at some length the mischief that flows from a naive understanding of the interplay of genetic and epigenetic events in determining behavior. I will not belabor that point further. I suggest, however, that there is still another area of misunderstanding that needs the spotlight directed on it. In general, the interfaces between academic disciplines in science are defined by emergent properties, and in this respect the line that has been drawn between the social and natural sciences is not unique. The field of chemistry exists to understand the stuff of which the world of our senses is made. This stuff, of course, consists of electrons and the elementary particles of atomic nuclei, but one can know a lot about elementary particles and not be adequately prepared to understand why CO2 is a gas and SiO2 is a rock. Similarly, the self-replicating chemical systems of cells represent another level of molecular organization with their own distinct properties.

Nevertheless, it is equally true that an understanding of chemical bonding in terms of atomic structure brings order to chemistry, and the enormous advances in this century in biochemistry and molecular biology would not have been possible without an appreciation of the various kinds of chemical bonds that exist in cells. The study of the chemistry of life was destined to flounder about in a hopeless fashion when our anchoring concepts were limited to chemically undefined colloids, coacervates, and soups. To be able to write on paper the primary structure (the sequence of amino acids) of a protein molecule is an organizing principle of the greatest importance, but it will not, in itself, show us the shape of the molecule in aqueous solution or how the molecule interacts with a substrate in enzymatically catalyzing a critical metabolic reaction. The latter are properties that follow from a more complex level of organization, but that, in their turn, can only be understood in a context that is consistent with, and incorporates the concepts of, the rest of physics and chemistry.

A similar relationship exists between the social sciences and biology. During the last thirty years, knowledge of the nervous system has increased at an ever-accelerating pace, and it is possible to identify a couple of its organizing principles. First, the dynamic properties of the nervous system are based on the propagation of impulses along nerve fibers and the interactions between cells that occur at structures called synapses. In a sense, synapses are analogous to chemical bonds, and not so many years ago many of us thought we understood the rules by which synapses work. Today it is clear that we understood only some of the rules; the discovery of neuro-active peptides and slowly acting synaptic transmitters and modulators makes it clear we still have a distance to travel. A second organizing principle of the nervous system is that in general particular functions are handled by specific populations of cells. This fact was obscured for a number of years because of the existence of parallel processing and other anatomical complexities, but today most neurobiologists enter the laboratory in the morning believing that the complex functions of higher neural circuits that generate behavior, including the mental activities of the human brain, will ultimately be understood in terms of (at the very least!) these two general principles.

All of this has to do with proximate cause. There have been some very interesting and parallel theoretical advances in evolutionary biology during the past twenty years that address matters of ultimate cause and that are of equally potential importance for the social sciences. By this I do not mean that anthropology, human psychology, and sociology will "reduce to biology" any more than biology has reduced to chemistry. Each level of organization is presented with properties that derive from the fact of organization and that have to be studied on their own terms. But those terms must relate to the rest of science or the exercise will be of no lasting value. The evolutionary concepts deal not primarily with physiology and chemistry but with biology's historical dimension: evolution. Evolution enters science with biology, but it is an exercise in self-deception to suppose that it leaves the cast when the social sciences come onto the stage. Cognitive psychologists certainly understand that their explanatory models must not only have heuristic value at their own descriptive levels, but, in some final sense, must also relate to the functions of neurons. Similarly, a larger problem facing the social sciences is to generate a theoretical architecture that neither clashes with biology nor consists of such exclusive structures that it is ultimately rendered irrelevant. "Biological reductionism" can be used to trivialize evolutionary biology in an effort to keep it at arm's length, but this is an unworthy goal. The social sciences will have matured only when they are firmly grounded in, and consistent with, the rest of our understanding of nature. In this enterprise, biology and the social sciences should work together, for the discovery of principles that can unite hierarchies and cut across species will enrich our knowledge and our lives. To date, only evolutionary biology offers that framework.

The Biological Roots of Human Nature. Forging Links between Evolution and Behavior
Epilogue: Concerning "Biological Reductionism"
Timothy H. Goldsmith, Oxford University Press, 1991

PS: Cartea o gasiti aici.

3 comentarii:

Tapirul spunea...

outstanding. nothing truer

sintetic spunea...

Coincidenta. Tocmai citeam Why Sex Matters: A Darwinian Look at Human Behavior de Bobbi S. Low.

Vorbind despre intelegerea comportamentului uman el spune acelasi lucru: e aberant sa nu folosim aceleasi instrumente care ne-au ajutat sa intelegem ecologia comportamentala a celorlalte specii. Aroganta cu care ne consideram "superiori" nu face decat sa franeze cunoasterea.

Turambar spunea...

Yup. Antroponcentrismul arogant dauneaza grav limpezimii de intzelegere a creerului stiintzific :)