Autopoiesis and a Biology of Intentionality∗

Essay 1 Autopoiesis and a Biology of Intentionality∗ Francisco J. Varela CREA, CNRS—Ecole Polytechnique, Paris, France. ∗Parts of this text have been published in (Varela 1991). 4 Biology of Intentionality Francisco J. Varela 1.1 Introduction enumeration of properties. But what is this basic process? Its description must be situated at a very As everybody here knows, autopoiesis is a neolo- specific level: it must be sufficiently universal to al- gism, introduced in 1971 by H. Maturana and my- low us to recognize living systems as a class, without self to designate the organization of a minimal living essential reference to the material components. Yet system. The term became emblematic of a view of at the same time it must not be too abstract, that the relation between an organism and its medium, is, it must be explicit enough to allow us to see such where its self constituting and autonomous aspects dynamical patterns in action in the actual living sys- are put at the center of the stage. From 1971, until tem we know on earth, those potentially to be found now much has happened to reinforce this perspec- in other solar systems, and eventually those created tive. Some of the developments have to do with the artificially by man. As stated by the organizer of a notion of autopoiesis itself in relation to the cellular meeting on artificial life: “Only when we are able to organization and the origin of life. Much more has view life-as-we-know-it in the larger context of life- to do with the autonomy and self-organizing qual- as-it-could-be will we really understand the nature ities of the organism in relation with its cognitive of the beast” (Langton 1989b, p. 2). activity. Thus in contrast to the dominant cogni- Contemporary cell biology has made it possible tivist, symbol-processing views of the 70’s today we for some years now to put forth the characteriza- witness in cognitive science a renaissance of the con- tion of this basic living organization—a bio-logic— cern for the embeddedness of the cognitive agent, as that of an autopoietic system (from Greek: self- natural or artificial. This comes up in various labels producing—Maturana & Varela 1980; Varela et al. as nouvelle-AI (Brooks 1991c), the symbol ground- 1974). An autopoietic system—the minimal living ing problem (Harnad 1991), autonomous agents in organization—is one that continuously produces the artificial life (Varela & Bourgine 1992), or situated components that specify it, while at the same time functionality (Agree 1988), to cite just a few self- realizing it (the system) as a concrete unity in space explanatory labels used recently. and time, which makes the network of production Any of these developments could merit a full talk; of components possible. More precisely defined: An obviously I cannot do that here. My intention autopoietic system is organized (defined as unity) as rather, profiting from the position of opening this a network of processes of production (synthesis and gathering, is to try to indicate some fundamental destruction) of components such that these compo- or foundational issues of the relation between au- nents: topoiesis and perception. Whence the title of my talk: a biology of intentionality. Since the crisis of (i) continuously regenerate and realize the network classical cognitive science has thrown open the issue that produces them, and of intentionality, in my eyes autopoiesis provides a natural entry into a view of intentionalty that is (ii) constitute the system as a distinguishable unity seminal in answering the major obstacles that have in the domain in which they exist. been addressed recently. I’ll came back to that at Thus, autopoiesis attempts to capture the mech- the end. Let me begin at the beginning. anism or process that generates the identity of the living, and thus to serve as a categorical distinc- 1.2 Cognition and tion of living from non-living. This identity amounts to self-produced coherence: the autopoietic mecha- Minimal Living Systems nism will maintain itself as a distinct unity as long as its basic concatenation of processes is kept in- 1.2.1 Autopoiesis as the tact in the face of perturbations, and will disappear skeletal bio-logic when confronted with perturbations that go beyond a certain viable range which depends on the specific The bacterial cell is the simplest of living sys- system considered. Obviously, all of the biochemi- tems because it possesses the capacity to produce, cal pathways and membrane formation in cells, can through a network of chemical processes, all the be immediately mapped onto this definition of au- chemical components which lead to the constitution topoiesis. of a distinct, bounded unit. To avoid being triv- A different exercise—which I do not pursue here ial, the attribute ‘living’ in the foregoing description at all—is to see how this basic autopoietic orga- must address the process that allows such consti- nization, present at the origin of terrestrial life tution, not the materialities that go into it, or an (Fleischaker 1988), becomes progressively complexi- 5 Biology of Intentionality Francisco J. Varela fied though reproductive mechanisms, compartmen- 1.2.2 Identity of the living talization, sexual dimorphism, modes of nutrition, and its world symbiosis, and so on, giving rise to the variety of pro- and eukaryotic life on Earth today (Margulis Autopoiesis addresses the issue of organism as a 1981; Fleischaker 1988). In particular, I take here minimal living system by characterizing its basic the view that reproduction is not intrinsic to the mode of identity. This is, properly speaking, to minimal logic of the living. Reproduction must be address the issue at an ontological level: the ac- considered as an added complexification superim- cent is on the manner in which a living system be- posed on a more basic identity, that of an autopoi- comes a distinguishable entity, and not on its spe- etic unity, a complexification which is necessary due cific molecular composition and contingent histori- to the constraints of the early conditions on a turbu- cal configurations. For as long as it exists, the au- lent planet. Reproduction is essential for the viabil- topoietic organization remains invariant. In other ity of the living, but only when there is an identity words, one way to spotlight the specificity of au- can a unit reproduce. In this sense, identity has topoiesis is to think of it self-referentially as that logical and ontological priority over reproduction, organization which maintains the very organization although not historical precedence. itself as an invariant. The entire physico-chemical We do not pursue here these historical complexi- constitution is in constant flux; the pattern remains, fications, neither do I pursue another equally perti- and only through its invariance can the flux of real- nent empirical question: Can a molecular structure izing components be ascertained. simpler than the already intricate bacterial cell, sat- I have addressed here only the minimal organiza- isfy the criteria of autopoietic organization? This tion that gives rise to such living autonomy. As I question can be answered by two complementary ap- have said, my purpose is to highlight the basic bio- proaches: (1) simulation and (2) synthesis of mini- logic which serves as the foundation from which the mal autopoetic systems. There are advances in both diversity visible in current organisms can be consid- fronts. As to the first, there some new results in ered: only when there is an identity can elaborations the burst of work in artificial life, partly extend- be seen as family variations of a common class of living our early simulations in tesselation automata ing unities. Every class of entities has an identity of (Varela et al. 1974). The second front, takes which is peculiar to them; the uniqueness of the liv- the form of a new ‘cell-centered’ approach to the ing resides in the kind of organization it has. origin of life which seeks chemical embodiments of Now, the history of biology is, of course, minimal autopoietic systems. In fact, the encapsu- marred by the traditional opposition between lation of macromolecules by lipid vesicles has been the mechanist/reductionists on the one hand and actively investigated as a promising candidate for holist/vitalists on the other, a heritage from the bi- an early cell (Deamer & Barchfeld 1982; Lazcano ological problem-space of the XIXth century. One 1986; Baeza et al. 1987; see Deamer 1986). Luisi of the specific contributions of the study of self- & Varela (1989) make the case that a reverse micel- organizing mechanisms—of which autopoiesis is a lar system can come close to the mark for being a specific instance—is that the traditional opposition minimal autopoietic system. In particular, they dis- between the component elements and the global cuss the case of a reverse micellar system hosting in properties disappears. In the simple example of the its aqueous core a reaction which leads to the pro- cellular automaton illustrated above, it is precisely duction of a surfactant, which is a boundary for the the reciprocal causality between the local rules of in- reverse micellar reaction. The interest of this case teractions (i.e. the components’ rules, which are akin is that much is known about these chemical systems to chemical interactions) and the global properties making it possible to actually put into operation a of the entity (its topological demarcation affecting minimal autopoietic system. But I must leave these diffusion and creating local conditions for reaction) fascinating issues to return to my chosen topic here. which is in evidence. It appears to me that this reciprocal causality does much to evacuate the mechanist/vitalist opposition, and allows us to move into a more productive phase of identifying various modes of self-organization where the local and the global are braided together explicitly through this reciprocal causality.

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