The following basic question is studied here: In the relatively stable molecular environment of a vertebrate body, can a dynamic idiotypic immune network develop a natural tolerance to endogenous components? The approach is based on stability analyses and computer simulation using a model that takes into account the dynamics of two agents of the immune system, namely B-lymphocytes and antibodies. The study investigates the behavior of simple immune networks in interaction with an antigen whose concentration is held constant as a function of the symmetry properties of the connectivity matrix of the network. Current idiotypic network models typically become unstable in the presence of this type of antigen. It is shown that idiotypic networks of a particular connectivity show tolerance towards auto-antigen without the need for ad hoc mechanisms that prevent an immune response. These tolerant network structures are characterized by aperiodic behavior in the absence of auto-antigen. When coupled to an auto-antigen, the chaotic attractor degenerates into one of several periodic ones, and at least one of them is stable. The connectivity structure needed for this behavior allows the system to adopt particular dynamic concentration patterns which do not lead to an unbounded immune response. Possible implications for the understanding of autoimmune disease and its treatment are discussed.

It is generally agreed that organisms are Complex Adaptive Systems. Since the rise of Cybernetics in the middle of the last century ideas from information theory and control theory have been applied to the adaptations of biological organisms in order to explain how they work. This does not, however, explain functionality, which is widely but not universally attributed to biological systems. There are two approaches to functionality, one based on etiology (what a trait was selected for), and the other based in autonomy. I argue that the etiological approach, as understood in terms of control theory, suffers from a problem of symmetry, by which function can equally well be placed in the environment as in the organism. Focusing on the autonomy view, I note that it can be understood to some degree in terms of control theory in its version called second order cybernetics. I present an approach to second order cybernetics that seems plausible for organisms with limited computational power, due to Hooker, Penfold and Evans. They hold that this approach gives something like concepts, certainly abstractions from specific situations, a trait required for functionality in its system adaptive form (i.e., control of the system by itself). Using this cue, I argue that biosemiotics provides the methodology to incorporate these quasi concepts into an account of functionality.

Covalent bonding within chemical molecules and the internal electronic structure of atoms involve closure of phase relations in electronic wave functions, as suggested de Broglie by many years ago. The structures of crystals involving positive and negative ions can be understood in terms of replication of unit cells that may be classified in terms of symmetry. The main principle involved in crystal symmetry can be understood by examining possible patterns in decorative borders. A more widely applicable type of chemical closure occurs in oscillating reactions (dissipative structures), in which an autocatalytic process is balanced by some exit reaction. As is the case for the other types of chemical coherence, the number of distinct types of oscillating reactions is rather small. Otherwise puzzling aspects of human social and organizational behavior may be clarified by analogy with chemical oscillating reactions.

In sociology, there has been a controversy about whether there is any essential difference between a human being and a tool, or if the tool–user relationship can be defined by co-actor symmetry. This issue becomes more complex when we consider examples of AI and robots, and even more so following progress in the development of various bio-machine hybrid technologies, such as robots that include organic parts, human brain implants, and adaptive prosthetics. It is argued that a concept of autonomous agency based on organismic embodiment helps to clarify the situation. On this view, agency consists of an asymmetrical relationship between an organism and its environment, because the continuous metabolic and regulatory activity of the organism gives rise to its own existence, and hence its specific behavioral domain. Accordingly, most (if not all) of current technologies are excluded from the class of autonomous agents. Instead, they are better conceptualized as interfaces that mediate our interactions with the world. This has important implications for design: Rather than trying to help humans to achieve their goals by duplicating their agency in artificial systems, it would be better to empower humans directly by enhancing their existing agency and lived experience with technological interfaces that can be incorporated into their embodiment. This incorporation might be especially facilitated by bio-machine hybrid technology that is designed according the principles of biological autonomy and multi-agent coordination dynamics.

Key words: Embodiment, consciousness, human–computer interface, agency

Upshot: Gibsonian and enactivist thinkers appear to diverge primarily with respect to the emphasis placed on the contributions of the organism to perception-action. Enactivists claim that a fundamental asymmetry in the organism-environment relationship should be credited for the existence of meaning in the world. Gibsonians counter that theory must reckon with both the asymmetry and symmetry between organism and environment as well as with the role of specificational information in underwriting their coordination.

Open peer commentary on the article “Eigenform and Reflexivity” by Louis H. Kauffman. Upshot: The intimate connection between eigenform and symmetry is illustrated, providing insight into the relevance of eigenform to physical science. Eigenform is also explored in the context of the first distinction.

We propose a conceptual and formal characterisation of biological organisation as a closure of constraints. We first establish a distinction between two causal regimes at work in biological systems: processes, which refer to the whole set of changes occurring in non-equilibrium open thermodynamic conditions, and constraints, those entities which, while acting upon the processes, exhibit some form of conservation (symmetry) at the relevant time scales. We then argue that, in biological systems, constraints realise closure, i.e. mutual dependence such that they both depend on and contribute to maintaining each other. With this characterisation in hand, we discuss how organisational closure can provide an operational tool for marking the boundaries between interacting biological systems. We conclude by focusing on the original conception of the relationship between stability and variation which emerges from this framework. – Highlights:Biological systems realise both organisational closure and thermodynamic openness, Organisational closure is a closure of constraints, Constraints exhibit conservation (symmetry) at the relevant time scales, Closure draws the boundaries between interacting biological systems, Closure is a principle of biological stabilisation.

Key words: Biological organisation, Closure, Constraints, Symmetries, Time scales

This paper gives a critical evaluation of the philosophical presuppositions and implications of two current schools in the sociology of knowledge: the Strong Programme of Bloor and Barnes; and the Constructivism of Latour and Knorr-Cetina. Bloor’s arguments for his externalist symmetry thesis (i.e., scientific beliefs must always be explained by social factors) are found to be incoherent or inconclusive. At best, they suggest a Weak Programme of the sociology of science: when theoretical preferences in a scientific community, SC, are first internally explained by appealing to the evidence, e, and the standards or values, V, accepted in SC, then a sociologist may sometimes step in to explain why e and V were accepted in SC. Latour’s story about the ‘social construction’ of facts in scientific laboratories is found to be misleading or incredible. The idea that scientific reality is an artifact turns out to have some interesting affinities with classical pragmatism, instrumentalism, phenomenology, and internal realism. However, the constructivist account of theoretical entities in terms of negotiation and social consensus is less plausible than the alternative realist story which explains consensus by the preexistence of mind-independent real entities. The author concludes that critical scientific realism, developed with the concept of truthlikeness, is compatible with the thesis that scientific beliefs or knowledge claims may be relative to various types of cognitive and practical interests. However, the realist denies, with good reasons, the stronger type of relativism which takes reality and truth to be relative to persons, groups, or social interests.

The structure of David’s Bloor argument for the Strong Programme (SP) in Science Studies is criticized from the philosophical perspective of anti-skeptical, scientific realism. The paper transforms the common criticism of SP – that the symmetry principle of SP implies an untenable form of cognitive relativism – into the␣clear philosophical issue of naturalism versus Platonism. It is also argued that the concrete patterns of SP’s interest-explanations and its sociological definition of knowledge involve philosophical skepticism. It is claimed, then, that the most problematic elements of SP reside primarily in philosophical skepticism. It is also claimed that this sort of criticism can be directed against other more radical, versions of constructivism in science and science education studies.

Purpose: This article investigates the emergence of subsystems in societies as a solution to the double contingency problem. Context: There are two underlying paradigms: one is radical constructivism in the sense that perturbations are at the centre of the self-organising processes; the other is Luhmann’s double contingency problem, where agents learn anticipations from each other. Approach: Central to our investigation is a computer simulation where we place agents into an arena. These agents can learn to (a) collect food and/or (b) steal food from other agents. In order to analyse subsystem formation, we investigate whether agents use both behaviours or just one of these, which is equivalent to determining the number of self-referential loops. This is detected with a novel measure that we call “prediction utilisation.” Results: During the simulation, symmetry breaking is observed. The system of agents divides itself up into two subsystems: one where agents just collect food and another one where agents just steal food from other agents. The ratio between these two populations is determined by the amount of food available.

Key words: Social systems, constructivist paradigm, cybernetics, double contingency, symmetry breaking, emergence