Beyond Digital Naturalism

The success of Artificial Life depends on whether it will help solving the conceptual problems of biology. Biology may be viewed as the science of the transformation of organizations. And, yet, biology lacks a theory of organization. We use this as an example of the challenge that Artificial Life must meet. "If as I believe physics and chemistry are conceptually inadequate as a theoretical framework for biology, it is because they lack the concept of function, and hence that of organization. [...] [P]erhaps, therefore, we should give the [...] computer scientists more of a say in the formulation of Theoretical Biology." Christopher Longuet-Higgins, 1969 [28] 1 Life and the organization problem in biology There are two readings of "life": "life" as an embodied phenomenon and "life" as a concept. Foucault [20] points out that up to the end of the eighteenth century life does not exist: only living beings. Living beings are but a class in the series of all things in the world. To speak of life is to speak only in the taxonomic sense of the word. Natural history dominated the Classical age and is foremost a naming exercise. "The naturalist is the man concerned with the structure of the visible world and its denomination according to characters. Not with life." (p.161). There is a concurrent interest in how things work, but it is an interest that remains disconnected and in tension with the naturalist tradition. In the early nineteenth century natural history makes a decisive step towards a biology when the notion of character becomes subordinate to the notion of function, when classification becomes comparative anatomy. Life is conceptualized as something functionally organized, and organization is foreign to the domain of the visible. A character is weighted according to the importance of the function(s) it is linked to. In contrast to the Classical age, characters are seen as signs of an invisible deep structure. Causal argumentation is reversed: a character is not important because it occurs frequently, but rather it occurs frequently because it is functionally important. Life as a concept becomes manifest as organization, organic structure, that is: organism. In the Classical period living beings were perceived largely as points in a coordinate system of names. Now they require an additional "space of organizational structure". This sets the stage for considering the problem of the modification and transformation of organization. Darwin posited evolution as an effect of what basically amounts to be a force [39]: natural selection. Natural selection is a statement about kinetics: in a population, those variants of organisms will accumulate which are better able to survive and reproduce than others. If there is on-going variation and if variation is (at least partially) heritable, then the continuous operation of selection kinetics will lead to the modification of living organizations. One would like, however, to understand how organization arises in the first place. Darwin's theory is not intended to answer this. Indeed, this is apparent upon inspection of the formal