Formal biological social science
Formal biological social science, like formal biology, develops abstract formal models (see endnote i) to provide explanations of the evolution of human society and culture. The basic structure of this framework was developed by Hamilton, Wilson, and Dawkins during the 1960s and 1970s. For example, Hamilton's inclusive fitness theory has been used extensively by, for example, Wilson to explain putatively problematic phenomena such as social altruism and group cohesion (Wilson 1975). It is worth pointing out that Hamilton eventually abandoned his own inclusive fitness framework for a formal hierarchical selection approach (Hamilton 1975). This occurred especially as a consequence of Hamilton's interactions with George Price (see, e.g., Price 1970; 1995; the latter paper appeared posthumously and was edited by Steve Frank). However, many of Hamilton's followers, including sociobiologists such as Wilson, continued to use his earlier approach of explaining human evolution as a result of maximizing gene-levelcentered inclusive fitness. I will not here concern myself further with sociobiology as it has been explored in detail elsewhere (e.g., Segerstrale 2001). The genetic determinism and adaptationism of sociobiology is a well-known attempt at synthesizing biology and social science using the formal and conceptual tools of neo-Darwinian evolutionary genetics.
Here, I want to focus on both Dawkins' framing attempts as presented in his famous best-seller The Selfish Gene, and two recent attempts to address – employing formal methods - the relationship between biology and culture. I will not examine in detail either Cavalli-Sforza and Feldman's or Boyd and Richerson's mathematical attempts to analyze the biology-culture relation, but will, instead present their remarkable ways of framing these issues.
Dawkins analyzed culture in terms of units that can be transmitted and which have differential fitness: 'Cultural transmission is analogous to genetic transmission in that, although basically conservative, it can give rise to a form of evolution' (1976, 203). He called these replicator units 'memes': 'Examples of memes are tunes, ideas, catch-phrases, clothes fashions, ways of making pots or of building arches' (1976, 206). He speaks of meme pools, survival value of memes, meme mutations and copy-fidelity, and meme inheritance from 'brain to brain via a process which, in the broad sense, can be called imitation' (1976, 206). This is a particularly clear case of framing an analysis in a new domain (i.e., culture) based on previously developed theoretical tools and concepts (i.e., the formal style of evolutionary biology). While it is true, as the philosopher of biology, Kim Sterelny, has pointed out to me, that in his The Selfish Gene, Dawkins neither presents a single mathematical model nor (practically ever) discusses mathematics directly, this book was, in effect, a condition for the possibility of, or at the very least, helped set the stage for, formal work on cultural transmission.
Cavalli-Sforza and Feldman (1981) developed a mathematically-rich theory of cultural transmission and evolution. They 'accept as culture those aspects of "thought, speech, action [meaning 'behavior' (CS&F)], and artifacts" [a definition of culture that they take from Webster's Dictionary] which can be learned and transmitted' (1981, 10). They then differentiate two levels of selection, natural and cultural, pertinent to two orders of organisms, first-order organisms (e.g., humans) and second-order organisms (e.g., cars and violins) (1981, 14-19). They note that classic Darwinian fitness and natural selection pertains to first-order organisms, whereas cultural selection, involving both learning and acceptance, is relevant to the cultural trait, that is, the second-order organism. They define cultural selection as 'the rate or probability that a given innovation, skill, type, trait, or specific cultural activity or object - all of which we shall call, for brevity, traits - will be accepted in a given time unit by an individual representative of the population' (1981, 15). The objects of cultural selection are conceptually consistent with Dawkins' memes. Both second-order organisms and memes are theoretical constructs of cultural 'traits' that meet the requirements of evolution by natural selection (i.e., heritable variance in fitness). A formal theory of transmission and selection can therefore be developed for them.
In this context, it is of interest to cite, at length, a key methodological passage from Cavalli-Sforza and Feldman:
'We have chosen to develop a mathematical theory, and we are well aware of the serious disadvantages that result from this decision. The necessary oversimplification is usually so great, especially in the applications to human behavior, that there is often a danger of distortion. Our position however, is that a mathematical theory is always more precise than a verbal one, in that it must spell out precisely the variables and parameters involved, and the relations between them. Theories couched in nonmathematical language may confound interactions and gloss over subtle differences in meaning. They avoid the charge of oversimplification at the expense of ambiguity. Another reason for favoring a mathematical treatment is our belief that the theory of biological evolution owes much of its present strength to its mathematical background, primarily in population genetics. Quantitative predictions can provide the potential to test the validity of the quantitative theory' (Cavalli-Sforza & Feldman 1981, v-vi).
Cavalli-Sforza and Feldman have faith in the importance of mathematical theory, particularly that stemming from population genetics. And although they differentiate Darwinian/biological selection from cultural selection, their models and modeling methodology vis-à-vis cultural selection very much follow in the vein of the formal theory of population genetics.
Boyd and Richerson (1985) published their book a few years later and make explicit and repeated reference to Cavalli-Sforza and Feldman's text. In their work they provide two introductory and conceptually rich chapters, entitled 'Overview' and 'Some Methodological Preliminaries', from which I will highlight some ideas. First, they take issue with critics of any form of biological social science who claim that 'because humans acquire so much of their behavior culturally rather than genetically, the human evolutionary process is fundamentally different from that of other animals'. In contrast, they note, 'since the neo-Darwinian theory of evolution does not explicitly account for the cultural transmission of behavior from one generation to the next, there has been no way of knowing whether this argument is cogent' (1985, 1-2, emphasis mine). And, although they are rather humble in their presentation of results, they do claim that:
'There are important differences between the genetic and cultural inheritance systems, and the theory will by no means neglect them. However, the parallels are profound enough that there is no need to invent a completely new conceptual and mathematical apparatus to deal with culture' (1985, 4, emphasis mine).
The 'not-completely-new' apparatus that they develop is what they call 'dual inheritance theory' in which 'the determinants of behavior are assumed to be transmitted via two structurally different inheritance systems' (1985, 2). In effect, they claim, there are two channels of transmission. In discussing the function, in the sense of the origin, of the two systems, they note that: '[W]e will argue that the structural differences between the two systems may well have arisen because the two systems are functionally analogous, that is, both systems serve to enhance ordinary Darwinian fitness' (1985, 31). Given that they do not make a distinction between two levels of selection or two orders of organisms, this theoretical structure does, admittedly, exhibit important differences with the theories proposed by Cavalli-Sforza and Feldman, as well as by Dawkins. Darwinian fitness is a sufficient and ubiquitous measure of selection for Boyd and Richerson, but not for Cavalli-Sforza and Feldman or Dawkins. Despite this, the similarities vis-à-vis presenting a formal theory in the spirit of Neo-Darwinian evolutionary genetics are far more important than the differences.
Thus far, I have briefly described some of the arguments that ground two formal frameworks that serve as key examples of formal biological social science. One last point, pertinent to this issue of GJSS, needs to be made with respect to these modeling attempts. Both books espouse a unificationist view of mathematical theory and, thus, implicitly, accept what one can call an epistemic or theoretical monism: that there is one correct way to develop and understand our theories. Given space constraints, two quotes will have to suffice to justify my claim. In the first paragraph to their preface, Cavalli-Sforza and Feldman note that:
'What emerges from the theoretical analysis [of cultural transmission] is the idea that the same frame of thought can be used for generating explanations of such diverse phenomena as linguistics, epidemics, social values and customs, and the diffusion of innovations' (1981, v, emphasis mine).
The desire and reality for unification, especially in the context of producing explanations, is here clearly manifested.
In a discussion of 'the utility of general theory', Boyd and Richerson state that:
'The most important function of general theory is to link the many disciplines contributing to the understanding of a complex problem like the evolution of human behavior. The general theory suggests what properties of sample theories [simple models that also have some generality – these desiderata are "competing", pp. 24-25 ] are essential in order to make the theory complete. It makes it possible to deduce the consequences of alternative sample theories in one discipline for the phenomena studied by another' (1985, 27, emphasis mine).
Clearly, there is also a general desire here for theoretical unification. While neither of these sets of authors explicitly claim that their models and modeling methodology is the only way to understand the relation between the biological and social, I think that given their defense of mathematical modeling (see also Boyd & Richerson 1985, 30-31) in the context of neo-Darwinian theory, as well as their explicit defense of unification, they do, in fact, adopt a theoretical monism. This seems to be an implicit assumption, in significant respects, in the formal style; it is a less prevalent commitment in the compositional style.