closure, identity, and the emergence of formal causation

112

Closure, Identity, and the Emergence of Formal Causation

ALVARO MORENO

a

Department of Logic and Philosophy of Science, University of the Basque Country, San Sebastián, Spain

A

BSTRACT

: The aim of this paper is to characterize a type of causality relevantto study the closure of complex systems that we call

formal causation

. By thisterm we understand the existence of a new (not materially inherent) causalrelation among constituents, generated through an autonomous process ofclosure. Once a certain level of organization is reached, material systems cangenerate internal constraints that, through recursive processes, construct theirown identity. We study two different forms of closure: closure in dissipativesystems and closure in template self-replication. Finally, these two formsmerge and bring forth a new one: informational closure, We show how com-plex forms of organization are based on informational closure, which is anexplicit, recorded type of formal causation allowing a functional articulationbetween individual organizations and larger, collective and historical(meta)organizations.

INTRODUCTION

The physical world has an intrinsic structure that reflects an inherent causal order.This inherent and universal causal order is the expression of what we call here

phys-ical or material causation

. However, this does not mean that all events are causal—chance exists—nor does it mean that all causal events are manifestations of thatbasic structure of matter.

In fact, these last two statements are related. For, if such a basic structure doesnot determine all regular, causal, relations that have progressively and locallyappeared in highly evolved natural systems (like biological and cognitive systems),then chance must play a fundamental role in their origin.

Of course, these new forms of organization cannot modify the basic, intrinsic,level of the causal relations in the world (i.e., universal material causation). What isparticular about these new forms of causal action is their functionality and autono-my. The first point is demonstrated by the fact that they are manifested as processesthat generate components and relations, whose effects contribute, recursively, to thegeneration of the actual

initial

processes (contributing in this way to the maintenanceof the forms of organization that generate them). The second point is shown by thefact that they self-generate through different forms of closure.

a

Address for correspondence: Department of Logic and Philosophy of Science, University ofthe Basque Country, Post Box 1249, 20080 San Sebastián, Spain. Voice: 34-943-018249; fax:34-943-311056.

[email protected]

113MORENO: EMERGENCE OF FORMAL CAUSATION

In other words, certain sets of material aggregates, under particular conditions,get self-restructured, that is, they over-determine themselves according to a circularcausal relation. Such causal actions become manifest in the creation of new forms ofcohesion and, thus, in the appearance of new forms of organization.

This type of causal action is

formal

in the sense that it infuses forms, that is, it

materially restructures matter according to a form.

It acts materially, in the sensethat formal causation requires complex and specific aggregates of matter and specificand controlled flows of energy. Furthermore, this restructuring of matter (which inits most basic expression is a given pattern) brings forth and stabilizes a possible—but improbable—material organization. (This structuring causal action or form doesnot have the power to alter the relations determined by intrinsic and universal mate-rial causation, but to select among different possible alternatives.

1

Therefore, its roleis to constitute second-order entities, i.e., entities created through structuring unitsthat are intrinsically constituted by material causation.)

Accordingly, formal causation is quite different from physical or material causa-tion. Whereas physical causation lies on the intrinsic activity of matter, whose pro-cesses do not require underlying levels of organization, formal causation needsunderlying levels of material organization and produces local rearrangements ofmatter.

2

LEVELS OF FORMAL CAUSATION

As a result of the intrinsic material causal action, the universe has evolved pro-ducing in some places forms of order (like rocks or galaxies), whereas, in others,matter shows no cohesion at all (such is the case of gases, for instance, except for theactual structure of the molecules that constitute it). This ordered matter, in turn, takestwo different forms: in some cases, basic components appear lumped together con-stituting fixed structures; and in others, they constitute dynamic structures. The firsttype refers to spatially ordered forms of assemblage of material subunits, where thisorder is temporally instantaneous, as in rocks or crystals. On the other hand, dynamicstructures are forms of order temporally unfolded, intrinsically dynamic, like atomsor planetary systems. Both types of ordering are, however, energetically stable.Thus, in both types of system the form exhibited is just an expression of the intrinsicnature of a set of components that interact under certain conditions, something thatwill stay indefinitely once created: that is, energetically all these systems are conser-vative.

Nevertheless, under special conditions, the generation of coherent assemblages ofmatter formed by elements whose cohesion would be impossible under thermody-namic equilibrium conditions, is also possible. Thus, their maintenance requires acontinuous input of energy. These are thermodynamic dissipative systems. Examplesof this type of system are whirls, hurricanes, oscillatory chemical reactions or livingbeings.

All these different systems have in common the fact that their internal organiza-tion (their dynamic cohesion) is not only a consequence of the material features oftheir components, but also of the achievement and maintenance (remote from equi-librium conditions) of some type of internal closure. Hence, through some sort of

114 ANNALS NEW YORK ACADEMY OF SCIENCES

dynamic circularity, these systems are able to generate and maintain a new type ofcorrelation among elements that, in the absence of such circular organization, wouldremain disconnected.

We distinguish here four fundamental classes within this general type of systems:basic dissipative system, self-replicating template systems, basic autonomous sys-tems, and living beings.

Basic Dissipative Systems

The fundamental idea behind this kind of system concerns the phenomenon of“spontaneous pattern generation”. Typical examples are the different varieties of

dis-sipative structures.

3

These are systems far away from thermodynamic equilibrium inwhich instabilities can give rise to a coherent global behavior—provided that certainparameters are kept within critical limits. Nowadays, the list of cases that are studiedand classified under this label is very long: Belusov-Zhabotinsky reactions, chemicalclocks, Benard’s convection cells, hurricanes, solar spots, and a wide variety of otherexamples.

The origin of this basic self-maintained cohesion is as follows: Under certain cir-cumstances, systems of very many independent components tend to stabilize, creat-ing macroscopic patterns of spatial and/or temporal order. Fluctuations in anunstable thermodynamic regime bring about a long-range pattern that is subsequent-ly stabilized—against other fluctuations—by means of a constant energy flowthrough the system. Hence, this type of coherent behavior can only occur in opensystems far removed from equilibrium and where nonlinear processes take place.Furthermore, some of the parameters that define the system must be held within aparticular range of values; in particular the necessary flow of energy must be assured.If the limits are crossed, the phenomenon of pattern generation typically disappears.Therefore, the generated cohesion is nothing but a macroscopic correlation recur-sively maintained. The macroscopic pattern that organizes itself is made of partswhose configuration and mutual interaction determine dynamically the whole thatthey constitute (and which appears as a stable spatial–temporal entity). This is themost simple and fundamental type of closure. Thus, the appearance of this type ofclosure requires an organization where nonlinear micro–macro relations are held.

This type of minimum closure, linked to the phenomenon of pattern formationin self-organizing physical or chemical systems, is trivial in the sense that the self-generated pattern has no other function than that of contributing to its own recursivemaintenance in a fixed or rigid way. The recursiveness of this type of closure is self-maintained by means of a special set of external conditions that cannot be influencedor modified by the actual system. The form that is generated is a fixed point in a caus-al loop, bare of functional adaptability. It is a unique and strictly self-functionalform.

Hence, this type of system constitutes the most basic expression of formal causa-tion, since the causal action of this self-generated form maintains itself. The onlyrole that these emergent macroscopic structures play is their own exclusive mainte-nance. The

identity

of these systems is precisely such a macroscopic pattern thatrepresents the stabilization of particular relations among many microscopic compo-nents. Thus, this identity can be regarded as the spontaneous emergence of a globalconstraint recursively self-maintained.


Self-Replicating Template Systems

The basic principle of template copying lies on a type of assemblage governed byphysicochemical forces, where a certain target structure acts as a blueprint and theresult is the production of a copy of that structure. Accordingly, as long as a set ofbasic components is available in the environment (and provided that the process isthermodynamically spontaneous), the replicating process will continue indefinitely.(We use the term

replication

when we deal with a process of copying a certain struc-ture, and the term

reproduction

when it is an organization that gets copied.) Weshould distinguish between two different types of self-replication by template: sim-ple template self-replication, when the self-replicative function is a direct result ofthe target structure; and complex self-replication, when it is mediated.

Simple Template Self-Replication

The mechanism that rules this process of direct copy is produced (in a suitableenvironment) by the specificity of the target structure. The reordering of the compo-nents that are found in the environment and that will assemble to constitute the copyis caused by the material specificity and the spatial shape of the target structure.(In contrast to the form generated in dissipative systems that is only maintained bysome type of recursiveness or closure, the actual form of a template is a conservativestructure. The process of replication of that structure is not necessarily dissipativeeither case.) A simple example of this type of process would be the growth of a crys-tal, where, once a basic target unit has formed, this structure will act as a constraintfor some of the components that land on one of its surfaces. For instance, when somedislocation appears in the crystal growth (e.g., a screw dislocation), this new struc-ture can speed up the process of growth, at the same time preserving the actualdislocation.

Complex Self-Replication

This is a more interesting type of self-replication by template. It occurs in com-plex autocatalytic systems, where the process of self-replication of certain structures(polymers with template activity) takes place through the catalytic mediation of oth-er components. In this case a dissipative organization is required to achieve the rep-lication of the template structures. A typical example of this is found in polymer self-replication through autocatalytic networks, like the hypercycles.

4

The type of closure is rather different from that of dissipative systems. In the lat-ter, the organization is self-maintained on the basis of the dynamic properties of thesystem, which is necessarily far from equilibrium. In the case of closure by templatethe organization constitutes the energetic-material implementation of the spatial rep-lication of certain structures, whose spatial shape and specific materiality play anactive role in that replication. Therefore, in the case of complex self-replication, therecursive self-maintenance of the autocatalytic network is linked to the process ofreplication of the template components, as a result of a fixed-point property.

Although effecting out the actual self-replication of the (population of) templatecomponents involves a dissipative process, the propagation of the linear (1D)structure of these components is not dissipative, since this structure can be main-tained indefinitely without any energetic input. In this sense, the

identity

of the


replicating system is, in principle, alien to that of the dynamic system necessary forits implementation.

Furthermore, we have to mention here two other fundamental aspects of this com-plex type of self-replication. The first is that the population of self-replicating struc-tures can develop flexible forms of functionality through a process of evolution byvariation and selection. (In this type of system, the only way of expressing function-ality lies in the possibility that certain sequences have to change and improve, direct-ly or indirectly, the capacity for self-replication of the system.) These forms offunctionality are connected to the appearance of two different levels in the morphol-ogy of polymers—the sequential and the spatial structures—because certain varia-tions in the sequence may bring about more efficient processes of self-replication.(The principles of variation and selection in systems made of populations of self-replicating polymers can produce functional adaptation, for certain complex struc-tures may appear and be selected according to their greater capability to self-repli-cate, directly or indirectly.) The second aspect of relevance is that, even though theprocess of template self-replication depends on a particular morphology, in principlethis may be compatible with an open variability at the level of the sequence structureor, more accurately, of part of this structure. Although there is always some

transla-tion

of the one-dimensional structure to the three-dimensional structure, the way thisis expressed depends on diverse material factors. There are self-replicating polymersin which the three-dimensional structure is highly independent of its one-dimension-al structure (as in the case of DNA), and in others it is the opposite (as in proteins).Given the importance of a three-dimensional morphological stability to carry out thetemplate function, polymers with great capacity to express their one-dimensionalvariety in the three-dimensional structure cannot be good self-replicating structures.The second aspects makes possible the potential use of statistically generated (butthermodynamically stable) aperiodic structures as genetic records.

Minimal Autonomous Systems

The step immediately before the appearance of a full-fledged living system is theorigin of chemical networks able to maintain their own

organization

adaptively, car-rying out functional actions in a variable environment. We refer to these systems as(minimally) autonomous because, unlike basic dissipative structures (whose organi-zation depends on external boundary conditions), autonomous systems actively con-trol their external boundary conditions. In this way, they exhibit a diversity offunctional processes that allow the maintenance of their identity in a wide range ofconditions, even in temporary absence of an external input of energy. Therefore, asystem is really autonomous when it is capable to carry out actions that modify theenvironmental conditions in such a way that they contribute to the maintenance ofthe

subject

of those actions. (Due to the fact that autonomous systems take part inthe construction of their own boundary conditions, the type of closure is not triviallyfunctional, but adaptive.) Thus, an autonomous system is an

agent

, that is, an orga-nization that acts on its own behalf and that is source and recipient of its actions. Anautonomous system defines its own identity through its functional actions—literally,it constructs and reconstructs itself continuously. What are the minimal require-ments, in material and organizational terms, necessary to give rise to an autonomoussystem? According to our present knowledge of prebiotic evolution,

5–7

we should


imagine these hypothetical autonomous systems to be autocatalytic networks thatare able to build themselves recursively, creating a membrane that separates themfrom their environment, and able to

manage

the flows of energy necessary for oper-ating in that environment.

10

The relevance of the membrane in the origin of life wasalready emphasized by Oparin back in the twenties. More recently, and linked to atheory on biological autonomy, the autopoietic school has made this claim.

8,9

The appearance of such networks may be achieved only if some components (orcomponent aggregates) act as constraints on other components and on the physico-chemical transformation processes they go through. The result of that multiple con-straining action constitutes an autonomous system when a new set of componentsand aggregates is produced in a recursive way and becomes differentiated from itsenvironment.

Therefore, the key to basic autonomy lies on the generation of the suitable set ofconstraints: those that actually define the new rules of behavior of the system, itsboundaries, and the functional terms in which it is going to maintain the relationshipwith its environment. Such a set must include global and local constraints whose dif-ferent actions are well coordinated, ensuring the conditions under which the systemis physically viable.

10

This involves, on the one hand, developing mechanisms tosolve possible physicochemical problems (like the osmotic problem); and on the oth-er hand, articulating the main coupling mechanisms on which the energetic mainte-nance of the system is necessarily based: couplings with the external resources(transduction and transport mechanisms) and couplings among exergonic and ender-gonic processes within the system (by means of various energetic currencies). Thefundamental constraint that allows all this to be achieved is a

selective membrane.

a

Even if it is generated by the actual organization of the internal chemical network,the membrane itself plays a fundamental role in the control of the energy flowsrequired for the implementation/realization of that network.

The organization of an autonomous system is based on a specific form of closurethat involves some active, functional relation with the environment, that is, with whatis

outside

the system. Of course, there is some kind of

internal

closure in an auton-omous system; but at the same time, the viability of the system requires a functionalrelation of this with its environment (active and directed interchange of matter andenergy), which in turn implies another form of closure necessarily coupled to theprevious one, in such a way that they cannot exist without each other. (There is acomplementary relation analogous to that claimed by the theory of autopoiesis be-tween membrane and metabolism).

In causal terms, an autonomous system carries out an activity that functionallyrestructures its environment (formal causation), whereas the environment only inter-acts in a physicochemical sense with the system. Hence its identity as an

agent

, thatis, as a system that interacts with its environment in a different fashion than the en-vironment acts on the system. It acts functionally on that environment and thanks tothis, the system acquires autonomy with respect to external conditions.

a

The fundamental error of the theory of autopoiesis is to consider the membrane only from thepoint of view of its internal action, ignoring the crucial role played by its external functionalactivity. Hence the central relevance of the membrane (but an active and selectively permeablemembrane): it makes manifest the double dimension (relational-constructive and thermody-namic) of the functional closure that sustains the most basic form of autonomy.


This dimension is made manifest when the thermodynamic perspective is takeninto account, since this perspective puts in explicit terms the necessity to generatesome recursive mechanism able to compensate for the spontaneous tendency ofenergy to be transformed into less and less ordered forms. It is nothing but the logicof these mechanisms that forces us to regard the system as an agent that controls itslocal environment, and it is also from this type of reasoning that we understand whythese systems must show a capability to restructure not only matter and energy, in-tegrating them, but also that of their immediate environment.

Living Systems

The development of those autonomous systems that we examined in the previoussection is limited by a fundamental factor: the complete

immanence

of the mecha-nisms that organize the system. Since the mechanisms that constrain the system areexclusively generated inside the network of component production that these mech-anisms rearrange, such individual systems lack the temporal and spatial conditionsnecessary for developing more complex forms of organization.

This problem can only be solved with the creation of a mechanism that allows theevolution of the constraining components to

go beyond

the limits of the existence ofthe individual systems in which they operate. This way, the specification of theirorganization will not entirely depend on internally generated processes of self-organization. An important part of the organizing mechanism was generated in amuch wider temporal and spatial organization. In consequence, this specification ofthe individual organizations depended on

heritable

polymers (whose sequence isshaped through a historical and collective process of variation and selection) and thatare transmitted through the reproduction of these individual organizations. Thesepolymers must have been aperiodic crystalline structures

11

with template capacities,whose unlimitedly complex sequence could become a system of records able tospecify or in-form the organization of the individual organizations.

Subsequently, the specification of the individual organizations depended on sta-ble patterns, whose changes were relatively independent of the dynamics of the sys-tem that they shape or in-form. Accordingly, the sequential domain of thesecomponents could only be contingently linked to the dynamic domain of the organi-zation that they specify. This way, the construction of the sequence patterns of theserecord-components becomes an open process, and its causal action, through directedreproduction, contributes to the robustness of self-maintaining processes that aremuch more complex than in the previous case. Moreover, this fact makes possiblethe appearance of compositional relations in the domain of genetic–component se-quences, and, consequently, an unlimited expansion of the self-structuring capacitiesof material systems.

This process is the key to the origin of living systems. The fact that the organiza-tion of all living beings crucially depends on a hereditary system of records gener-ated in the context of a historical-collective

metanetwork

is quite reasonable after all:without component-records it would not have been possible to ensure either a reli-able reproduction of possible previous autonomous systems, or their evolutiontoward more complex forms.

Therefore, living beings are based on a combination of dynamic-dissipative clo-sure and template closure. Although at first sight the latter might seem to reduce the


adaptive flexibility of the system, it happens all the way round, since this is the basicmechanism that allows the complex expansion or unfolding of dissipative closure.This is due to the fact that the combination of the two types of closure creates twodifferent levels of adaptability (phylogenetic and ontogenetic).

This complementary type of closure, on the basis of the organization of all livingsystems, constitutes the most elemental form of information. Information appears inthe form of a set of

instructive

records that specify the construction of complex func-tional constraints of the basic organization of the living beings. However, in order totranslate the meaning of the information to the dynamic domain, part of these func-tional components need to interpret the informational instructions (i.e., establish thecoupling between the informational primitives and their functional

referents

—a taskthat is performed in the cell by the tRNA aminacylsynthetase enzymes. Hence, indi-vidual living beings are based on a new form of closure that H. Pattee

12

has called

semantic closure.

In causal terms, semantic or informational closure makes it possible for the sys-tem to develop a new capacity for restructuring its internal organization according to

forms

or patterns explicitly materialized, and which go beyond the actual system inwhich they are interpreted and operate. This causal action is much more effectivethan the implicit formal causation that takes place in basic autonomous systems, be-cause it allows fixing and transmitting functional causal links to be created throughnatural selection, out of the domain of the individual systems.

COMPARISON BETWEEN DIFFERENT TYPES OF CLOSURE

Dissipative-dynamic closure and template closure stand on the basis of two dif-ferent kinds of evolution. In the first case, evolution is toward flexible, dynamicallyadaptive-functional, forms of

organization

that depend on the synchrony of thedynamic times of environment and system to achieve higher levels of complexity.The idea of organization is linked to that of open construction and, hence, to the pos-sibility for open functionality since new components may contribute to the creationof new viable forms of self-maintaining organizations.

However, in the second case, we find that the idea of self-replication is not direct-ly linked to the concept of open functionality, because the organization that is nec-essary to carry out self-replication is not its actual target. The identity of a self-replicating system is a nondynamic shape or pattern in a space of possible configu-rations or structures. The different forms of identity of a self-replicating system arenot wholly involved in the self-replication process (they are not forced to participatecausally in its maintenance) and, thus, they do not necessarily imply functional vari-ations. It is true that the shape of the system plays a certain functional role in the self-replication process (particular changes in the replicated configuration have influenceon the organization that controls that process); even so, this does not necessarilyaffect the replicated configuration as a whole (otherwise, the potentiality to replicatean open variety of configurations would be lost).

Only when we speak about self-reproduction (i.e., the copying of an organization byitself) can we say that the situation is really different. This is because self-reproduction


is a particular case or type of autopoietic self-maintenance: that in which the recursiveself-production of the organization involves its spatial reproduction.

In living beings the evolution processes of systems based on template closure andon dissipative-dynamic closure converge. The sequences of template componentsspecify, by means of a codifying mechanism, those functional components necessaryfor the recursive maintenance of system organization; and this organization, in turn,interprets and carries out the replication of the template components. Yet, this com-plementary convergence does not erase the fundamental differences between the twotypes of closure: template processes (associated with the concept of genetic informa-tion) occurring in metaindividual times and spaces; and organizational, dissipativeprocesses (associated to the concept of phenotype) that are linked to the dynamics oftheir environment (see T

ABLE

).

FINAL REMARKS: CLOSURE IN A COLLECTIVE CONTEXT

Once an evolving organization based on the hereditary transmission of instructivestructures—genetic information—for the organization of individual autonomoussystems (that is, once template self-replication and functional-adaptive organiza-tions merge), the idea of

global autonomous system

becomes relevant. The main fea-tures of this type of (meta) system are as follows:

1. To be made of units that constitute themselves, autonomous systems infor-mationally instructed are able to interpret those instructions and are self-enclosed by a physical border.

2. To constitute food-webs, that is, collective metabolic organizations.3. To constitute globally a system of production of hereditary instructions

(i.e., of information) through natural selection of the phenotypes (i.e., ofthe individual dynamic expressions of the transmitted instructions).

TABLE. Comparison between systems in which different types of closure occur

System Dissipative structure

Autonomous Living being Complex replicator

Simple replicator

Main feature/property

pattern of

spatial/

temporal order

adaptive self-

maintenance

open-ended

evolution

adaptive self-

replication

direct self-

replication

Type of closure

dynamic functional informational mediated

template

direct

template

Type of formal causation

implicit

+

fixed

implicit

+

variable

explicit

+

linked to an

open-ended

construction

explicit none

Type of identity

organization agential

organization

duality

organization-

structure

adaptive

structure

structure


Is this metaorganization based in turn on some sort of closure? Considering the sys-tem in its most global sense, its continuous evolution is nothing but a (“red queen”)way of self-maintenance as an ecosystem; that is, as a set of units hierarchically andhistorically organized in terms of autonomy; ultimately, as a mega-system that con-tinuously creates and maintains functional relations—both internal and with the en-vironment—similar to the organization of basic autonomous systems, but withoutthe spatial requirement of generating a selective physical border for self-enclosure.

Paradoxically, complex organizations based on informational forms of closure(Pattee´s Semantic Closure), though autonomously constructed, are founded on awider, collective form of organization. The fundamental structure (still operationallyclosed) of this collective form of organization seems to be unchanged despite the factthat some of its parts have undergone deep changes, entailing an extraordinary in-crease in its complexity.

ACKNOWLEDGMENTS

The author acknowledges funding from Research Project Number PB95-0502 ofthe DGICYT-MEC, from BIO96-0895 of the CICYT, and from EX-1998-146 andHU-1998-142 of the Basque Government.

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closure, identity, and the emergence of formal causation

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