This is a great, deep, inspiring, and artfully argued plea for the unity of the sciences and humanities. Many have viewed this book as narrow-minded and reductionist, an extended argument that all humanly relevant phenomena can be "reduced to physics." This, I think, is a...
This is a great, deep, inspiring, and artfully argued plea for the unity of the sciences and humanities. Many have viewed this book as narrow-minded and reductionist, an extended argument that all humanly relevant phenomena can be "reduced to physics." This, I think, is a very narrow misreading of Wilson''s argument. Indeed, I found Consilience itself to be a carefully unified exercise in natural science/social science/artistic creation. Wilson has a shining human vision of the unity of cognition, emotion, and spirit that transcends traditional classificatory boundaries. "Neither science nor the arts can be complete without combining their separate strengths," says Wilson. "Science needs the intuition and the metaphorical power of the arts, and the arts need the fresh blood of science." (p. 230) Moreover, Wilson locates exactly the transmission channel between science and the arts. "Interpretation," he claims, "is the logical channel of consilient explanation between science and the arts." (p. 230)
Wilson''s basic argument is rather metaphysical and must, I believe, be taken on faith. "There is intrinsically only one class of explanation," he holds. "The central idea of consilience world view is that all tangible phenomena, from the birth of stars to the workings of social institutions, are based on material processes that are ultimately reducible, however long and tortuous the sequences, to the laws of physics." (p. 291) Wilson is not horribly dogmatic about this faith---he argues that there is increasing evidence for it, but he is prepared for its falsification if future evidence warrants it. Wilson''s faith is not severely reductionist because he sees the relationship between levels of complexity as a dialectic of reduction of the complex to its parts, and the synthesis of the whole from its parts, in full recognition that the backward movement is much simpler than the forward. Wilson recognizes the concept of complexity, according to which a higher level of organization cannot be predicted or fully understood in terms of the characteristics of its parts, but he does not go the whole complexity distance, which involves maintaining that a complex system has emergent properties that cannot, perhaps even in principle, be inferred from the characteristics of its parts. Indeed, the term "emergence" does not appear in the index to Consilience. Nevertheless, Wilson''s description of a consilient analysis of a complex structure (e.g., a eukaryotic cell) is quite detailed and to my mind accurate. He certainly never says we can capture the complex whole as the sum of its simpler constituents, although he correctly affirms that we should try to do so and may in important cases be successful.
To give a flavor of Wilson''s argument, consider the following. "To dissect a phenomenon into its elements, in this case the cell into organelles and molecules, is consilience by reduction. To reconstitute it, and especially to predict with knowledge gained by reduction how nature assembled it in the first place, is consilience by synthesis. That is the two-step procedure by which natural scientists generally work: top-down across three or four levels of organization at a time by analysis, then bottom up across the same levels by synthesis." (p. 74). Now, this is a grand description, but highly idealized. Certainly knowledge at a lower level is critical for understanding how a higher level works, but when there are emergent properties to the higher level, the synthesis of the lower level information is in itself incapable of reconstructing the whole. For instance, quantum mechanics is useful for analyzing the structure of chemical molecules, but is incapable of generating the higher level molecular models. Similarly, solid state physics helps understand the computer, but computer sciences is light-years away from being a branch of applied solid-state physics.
Wilson wants to see the unification of three spheres of human knowledge: natural science, social science, and the humanities/arts. As I pointed out above, "interpretation" is the key link between science and the arts. Wilson does not elaborate on this link, and I am not sure it has been followed up in the literature in the twelve years since Consilience was published. The link between natural science and social science, by contrast, is quite carefully elaborated. This link is "gene-culture coevolution." Since this phenomenon is part of biology, Wilson obtains the natural-social science link by placing biology among the natural sciences. This is fair enough, although I generally place the part of biology that deals with behavior, especially social behavior, in the "behavioral sciences, which in addition include economics, sociology, psychology, anthropology, and political science.
For Wilson''s purposes, including biology in the natural sciences and seeing gene-culture coevolution as the major linking mechanism is perfectly acceptable. In my own treatment of the unification of the behavioral sciences (The Bounds of Reason, Princeton, 2009), I argue that gene-culture coevolution is the first and most basic of five principles bridging the various social science disciplines. Because gene-culture coevolution is a key element of sociobiology, it is not surprising that Wilson was among the first to discuss the mechanism, positing the "culturgen" parallel to the "gene" as units of evolutionary dynamics (C. J. Lumsden and E. O. Wilson Genes, Mind, and Culture, Harvard University Press, Cambridge, MA, 1981). Other key figures in the development were Luca Cavalli-Sforza and Marcus Feldman Cultural Transmission
and Evolution, Princeton University Press, Princeton, NJ, 1981), and Robert Boyd and Peter J. Richerson, Culture and the Evolutionary Process, University of Chicago Press, Chicago, 1985).
What is gene-culture coevolution? Because of the importance of culture and complex social organization to the evolutionary success of Homo sapiens, individual fitness in humans depends on the structure of social life. Because culture is both constrained and promoted by the human genome, human cognitive, affective, and moral capacities are the product of an evolutionary dynamic involving the interaction of genes and culture. We call this dynamic gene-culture coevolution. This coevolutionary process has endowed humans with preferences that go beyond the self-regarding concerns emphasized in traditional economic and pre-sociobiology biological theory, and with a social epistemology that facilitates the sharing of intentionality across minds. Gene-culture coevolution is responsible for the salience of such other-regarding human values as a taste for cooperation, fairness, and retribution, the capacity to empathize, and the ability to value such character virtues as honesty, hard work, piety, and loyalty.
Gene-culture coevolution is the application of sociobiology, the general theory of the social organization of biological species, to humans--the only species that transmits culture in a manner that leads to quantitative growth across generations. This is a special case of niche construction, which applies to species that transform their natural environment so as to facilitate social interaction and collective behavior.
The genome encodes information that is used both to construct a new organism and to endow it with instructions for transforming sensory inputs into decision outputs. Because learning is costly and time-consuming, efficient information transmission will ensure that the genome encode those aspects of the organism''s environment that are constant, or that change only very slowly through time and space, as compared with an individual lifetime. By contrast, environmental conditions that vary rapidly can be dealt with by providing the organism with phenotypic plasticity in the form of the capacity to learn. For instance, suppose the environment provides an organism with the most nutrients where ambient temperature is highest. An organism may learn this by trial and error over many periods, or it can be hard-wired to seek the highest ambient temperature when feeding. By contrast, suppose the optimal feeding temperature varies over an individual''s lifetime. Then there is no benefit to encoding this information in the individual''s genome, but a flexible learning mechanism will enhance the individual''s fitness. There is an intermediate case, however, that is efficiently handled neither by genetic encoding nor learning. When environmental conditions are positively but imperfectly correlated across generations, each generation acquires valuable information through learning that it cannot transmit genetically to the succeeding generation, because such information is not encoded in the germ line. In the context of such environments, there is a fitness benefit to the transmission of epigenetic information concerning the current state of the environment. Such epigenetic information is quite common, but achieves its highest and most flexible form in cultural transmission in humans and to a considerably lesser extent in other primates.
The parallel between cultural and biological evolution goes back to Julian Huxley , Karl Popper , and William James. The idea of treating culture as a form of epigenetic transmission was pioneered by Richard Dawkins, who coined the term "meme" in The Selfish Gene to represent an integral unit of information that could be transmitted phenotypically. There quickly followed several major contributions to a biological approach to culture, all based on the notion that culture, like genes, evolve through replication (intergenerational transmission), mutation, and selection. Cultural elements reproduce themselves from brain to brain and across time, mutate, and are subject to selection according to their effects on the fitness of their carriers. Moreover, there are strong interactions between genetic and epigenetic elements in human evolution, ranging from basic physiology (e.g., the transformation of the organs of speech with the evolution of language) to sophisticated social emotions, including empathy, shame, guilt, and revenge-seeking.
Wilson''s treatment of ethics and religion are cogent and masterful. He contrasts two modes of thinking about morality, transcendentalist and empiricist. While recognizing the transcendentalist yearnings in the breast of most humans, and while acknowledging that religious sentiments of the transcendental sort are the product of gene-culture coevolution, he argues that the evidence is strongly on the side of empiricists, who recognize the human significance of ethics, but root ethics in material processes that have an existence independent from that of a transcendental God or Reason. On these grounds he faults not only Kant, but Moore and Rawls as well. For instance, he argues that Moore''s `Naturalistic Fallacy'' is itself a fallacy. "If ought is not is, then what is it?" (p. 273) In other words, everything that is, is part of some material process, so the transition between ought and is is not cross-category but rather within-category. This does mean that everything that is, ought to be, but rather, we determine the ethical principles that are valid for humans by studying how humans create and transform the moral lives.
The only drawback of this book is his treatment of the social sciences. Wilson is well-read in the various social sciences and his criticisms of sociology, anthropology, and economics are generally accurate, however harsh. His recommendation for reform is that they recognize gene-culture coevolution and reform their theories accordingly. However, he gives us no idea how to accomplish this. Fortunately, dear reader, I supply the answer in my book, The Bounds of Reason (Princeton 2009) and my forthcoming book with Samuel Bowles, A Cooperative Species (Princeton 2011). For other hints, see my web site [...]