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Emergence, directionality and finality in an evolutionary universe

2011

Biological Evolution: Facts and Theories

A conference held in 2009 at the Pontifical Gregorian University celebrated Charles R. Darwin’s anniversary (1809-1882) and hosted a number of lecturers coming from different scientific and humanistic areas. We present here the paper given by William R. Stoeger (1943-2014), a jesuit cosmologist active at the Vatican Observatory and renowned for his interdisciplinary production. Resuming the physical and biological history of the cosmos, Stoeger focuses on the notion of directionality, which he considers more adequate for a scientific audience that the notion of finalism. Emergence and directionality in the early universe is a scientific result, since the cosmos has slowly evolved from a simple to a complex structure, and life evolved from unicellular organisms to the complex brain of primates, among which human brain and human consciousness offer the most important examples. After examining the different levels of emergence and possible definitions of teleology, the Authors addresses the relevant question about the perception of finalism in the realm of natural reality: "From our discussions so far, is there any definite scientifically accessible way of reaching a conclusion on this issue? What about the anthropic principle, and the apparent fine-tuning of the universe it reveals? I am convinced that on the basis of our scientific findings so far, we have to conclude on strictly scientific grounds that there is no secure evidence of such a global finality. But, at the same time, there is also no scientific evidence ruling it out". Stoeger affirms that although we cannot argue it scientifically, since the Creator as Creator is inaccessible to the natural sciences, our scientific knowledge of physical and biological evolution supports a deep compatibility and consonance with our understandings of God and the Divine.

There is no doubt that, as the universe has evolved from the Big Bang, roughly 13.7 billion years ago, it has undergone continual differentiation and complexification. In the course of that cosmic history — and more recently in the history of our planet, the Earth — an amazing array of intricately related, and interdependent systems and networks of systems has emerged at all levels, and then evolved further into new systems and networks. Living organisms, and among them conscious, rational and freely choosing organisms, are the most notable of these. They exhibit capabilities and behaviors far beyond those of their basic components. This appearance of new objects and systems with qualitatively different and often more advanced capabilities and behaviors from networks of more simple ones is often referred to as “emergence” — for example the emergence of life, the emergence of consciousness, the emergence of intelligence. This does not mean that these emergent phenomena are not explainable in terms of the processes and relationships among lower-level systems and entities — these obviously provide the necessary conditions for life, consciousness and intelligence — but simply that such emergents and their properties and operations are not causally reducible to or determinable by their individual operations. This continually unfolding emergence of new and intricately organized systems and organisms strongly suggests a directionality in the history of the universe, and in the history of the Earth and of life on it — at least in the general movement from the very simple to increasing levels of complexity. And from that suggestion, which seems to reflect similar ideas of various philosophical and theological traditions, many recent interdisciplinary pundits postulate an overarching finality or teleology — a purposefulness — to the unfolding universe, and to nature itself as it evolves on Earth, and possibly elsewhere. This has been spurred by the controversial but very popular so-called “anthropic coincidences,” or “anthropic principle” (see Stoeger 2007, 445, and references therein), the recognition by many cosmologists and physicists, that the universe appears to be fine-tuned for complexity — and therefore for life and consciousness. In other words, if any one of a number of key physical or cosmological parameters — e. g., the strength of the gravity, the strength of the strong nuclear force, of electromagnetism, or the initial rate of expansion of the universe as it emerged from the Planck era (the Big Bang) — were just slightly different, the universe would be completely sterile — without the possibility of complexity and life. Though it seems impossible to either confirm or deny such an overarching cosmic purpose on the basis of the natural sciences alone, it is clear that within systems and organisms themselves, a certain local, focused teleology has emerged — as differentiated functionality. Each component of a complex system or organism has a particular function within it — a function which is often essential to its survival and integrity. We have for instance in the bodies of mammals the life-giving functions of the heart, the kidneys, the lungs, the brain and its key components. And as any system or organism is always a part of some larger system, organism or ecology, it in turn fulfils a certain function, or set of functions — which is often interpreted as having a certain “purpose” within that larger system. And natural selection itself supplies the preference for the organisms which are more fit and functionally adapted relative to a given environment. This itself implies a certain directionality, even finality. It is far from controversial to recognize this pervasive and amazing pattern of the emergence of novelty and incredible variety throughout the history of the cosmos and of the Earth. In this presentation I intend to reflect briefly but carefully on the general conditions and processes underlying this continuing emergence. It is somewhat controversial to go further and maintain that there is a general directionality to the unfolding cosmos — and to the overall evolution of systems within it. Among most biologists there is strong resistance to asserting that. However, there are some, along with a number of biophysicists, cosmologists, astrobiologists, and complex systems specialists, who strongly support this conclusion on scientific grounds. In order to do so, we need to understand what is meant — and what is not meant — by this directionality. I intend to explore this briefly, including a sketch of its scientifically accessible basis. By “directionality” in this sense — as a scientifically accessible or discernible movement — I do not mean one with a sin gle unique, or even definite, goal, but simply one which proceeds towards a definite range of possible outcomes — which become more focused and delimited as evolution continues. It is not necessarily goal determined — though it may be — but is primarily process driven. Specific processes naturally imply a limited range of outcomes. This continual emergence of novelty in nature — which, as I’ve already hinted, is really due to the rich differentiation of lower-level components and their internal and external synchronic and diachronic relationships (combinations and interactions) with one another and with their immediate environments — along with directionalities and functional teleologies they induce, reflects the deep consonance and compatibility of cosmological and biological conclusions about origins with the best that Jewish, Christian, and Muslim theologies of creation have to offer. This is not at all surprising, given that, from a theological perspective, Nature is the ongoing “work” of the Creator. Oftentimes, however, either our concepts of Creator and creation are so inadequate, or our interpretations of scientific conclusions so philosophically distorted or shallow, that an authentic and careful rapproachment between the two becomes nearly impossible. And finally I shall reflect briefly, and I hope carefully, on the scientifically controversial issue of teleology, both the teleological aspects stemming from functional differentiation within systems and organisms and the suggestion of an overarching teleology — or finality — for which some find support in contemporary physics, cosmology, chemistry and biology. Certainly the major theological traditions strongly affirm such a teleology — and major philosophical traditions have argued to that. But, to what extent can strictly scientific conclusions of natural sciences as such validly support a definite purpose to our universe? And whether or not they can, what are the scientifically accessible relationships, processes and regularities which effect the implementation of that overall teleological movement? These are the questions I shall attempt to answer provisionally here. 1. Emergence and directionality in the early universe Under the dominant influence of gravity, proto-galaxies condensed from the expanding cosmic hydrogen and helium (and a little bit of lithium, the lightest metal) — there were no other chemical elements — and then very soon the first stars appeared. As we have already stressed, only with stars were the elements beyond hydrogen, helium and lithium synthesized. Eventually, the stars and their remnants enriched the cosmos with carbon, oxygen, phosphorous, iron, silicon, and all the remaining 92 natural elements. But, in order for stars to form, a num ber of very delicate conditions had to be fulfilled. It is only because the universe has been expanding and cooling since the Big Bang and that gravity of a certain strength continues to operate — along with the precise strengths of the other basic physical interactions — that stars were able to form at all. In fact, if the universe had been expanding a little more quickly than it was at the beginning — or a little more slowly — stars would not have formed. In that case there would have been no chemistry — and the building blocks necessary for the eventual emergence of life would never have been produced. The universe would have remained sterile and boring forever! Thus, the expanding, cooling, complexifying history of the universe since the Big Bang 13.7 billion years ago provides the overarching, all-embracing physical directionality — and conditions — for cosmic, chemical and biological evolution (Stoeger 1998, 163; Davies 1998, 151). Although we cannot say precisely or in detail exactly what had to emerge from that process, it is clear — just from the way gravity operates and local matter condensations heat up on collapse — that the universe had to become lumpy on a number of scales, that those lumps would continue to interact gravitationally, and that within their internal stellar furnaces new — heavier — elements, with completely new properties would be manufactured. This is the basic directionality inherent in the cosmic system itself — given the laws of physics and certain “initial conditions” at any early stage we consider. Given those conditions then gravity and other physical regularities and relationships inevitably lead to a definite rather narrow range of outcomes. Possible future configurations and possibilities are tightly — though only rarely uniquely — restricted. In this early stage of cosmic evolution, there are two examples of lower level emergence worth examining briefly. First, there are the large, intermediate and smaller size gravitationally bound systems — galaxies, clusters of galaxies, stars and their planetary systems, and clusters of stars (e.g. globular clusters). Secondly, on the microscopic level, there is the formation of elements heavier than hydrogen and helium in cores of stars, and in supernova explosions. In the first case — astronomical systems — gravity and angular momentum conspired to act on density fluctuations in the cosmic plasma — once matter decoupled from radiation about 300,000 years after the Big Bang — to form this vast array of hierarchically ordered — diverse — systems of various sizes. And each of those continued — and continue — to interact and evolve in various ways, again because of gravity and angular momentum, among other lesser influences. In the second case, all the heavier elements and chemical compounds are gradually synthesized. Nuclear physics along with electromagnetism, acting within the evolving but specific conditions of temperature, pressure and chemical composition in stellar cores — and in the case of compounds in the cooler atmospheres of some stars or on planets — enable their formation. These elements and compounds have completely different properties and potentialities than the components from which they are formed. Why? Precisely because of the particular relationships between the particles (protons, neutrons and electrons) that make up the atoms, or between the atoms that make up compounds like salt and water. Salt, for instance, has completely different properties than the sodium and chlorine which constitute it. And the amazing substance water is very different from the hydrogen and oxygen from which it is synthesized. These are examples of emergence on the chemical level — and illustrative of the constitutive nuclear and chemical relationships which endow these substances with their novel characteristics and capabilities — their unique and very specific or focused ways of interacting with other substances in particular environments. Again, in systems involving given elements and compounds — under specific conditions — there is always a directionality. There is a directionality from the past to the present situation — dictating that this outcome, or one similar to it, will occur. And there is a directionality towards the future specifying a certain relatively narrow range of types of subsequent outcomes (Stoeger 1998, 163) — unless very different conditions and influences from outside the system under consideration intervene. 2. Pre-biology and the emergence of life and consciousness It is not possible in this very short and sketchy talk to summarize the various stages of evolution and the processes which are involved. I have spent time briefly describing the formation of simple physical systems in our universe, and that of the elements and simple compounds — because they are basic to everything else that follows and because already at those levels, it is clear that there is at least a type of emergence — depending upon networks of relationships and leading to differentiation, complexification and diversity — and, of course, a certain internal directionality. It is worth pointing out, too, that all this depends heavily on the fundamental order with which the universe is endowed — at the level of physics, and the chemical order which emerges from that as the elements are produced. This is connected, once more, to the “anthropic principle.” What is the origin of that order? And what enforces it, in such a way that higher levels of order emerge, as more complex systems and entities arise? I shall now very briefly speak of the processes that lead to and characterize the emergence and directionality at higher levels of complexity leading to life and consciousness, and then describe in outline the three general categories (levels) of emergent phenomena first given by Terrence Deacon (2006, 111; 2007, 88). Once we have diverse localized environments — say on a planet — characterized by very particular stationary conditions — or cycles of conditions — of temperature, pressure, alkalinity or acidity, chemical composition, available free energy, etc., various new chemical species are produced. And not only that but there will be chemical cycles involving a number of different but interrelated chemical species which manifest certain regularities within a given environment or ecology — some species, for instance, catalyzing the production of other species — and being catalyzed in turn by yet a third category. The evolution of such chemical systems, though self-sustaining for a time, will certainly change the environment — leading to other conditions, providing new niches for slightly or very different systems. These constitute new plateaus of organization stability, from which further evolutionary changes can take their departure. Or there may be an intrinsic or extrinsic alteration in the system — on the macroscopic or on the microscopic level — which drives its development in a different direction. In all cases, what is critical are the effective intrinsic and extrinsic relationships which effect the production — the emergence — of new and different systems, and the selective reinforcement of some types over others. This is already a primitive type of natural selection! This general pattern of system-building and networking develops even more potential when differentiated species of molecules (e.g. DNA or RNA) begin to carry detailed information which is implemented by other molecules (RNA or proteins), and reliably reproduce themselves within their chemical systems. This obviously allows for a detailed propagation of successful characteristics for flourishing in a given environment to later generations. With some mechanism of variation (e.g. genetic mutation or symbiotic incorporation) among the information carrying and information implementing molecules, new and more successful characteristics can develop and eventually dominate in the system. This is basically natural selection — considered to be the principal “process” responsible for biological evolution. But it is considered by many researchers in the field to be already important in advanced pre-biotic chemical networks — e. g. Manfred Eigen’s autocatalytic hypercycles (Eigen and Schuster 1978; Küppers 1983, 125). This is, as Bernd Olaf Küppers (1983, 2; 1990, 136) mentions, the crucial stage of instructed synthesis of molecules like nucleic acids and proteins, following the earlier more primitive stage of non-instructed synthesis of pre-biotic molecules, which provides the immediate building blocks for the emergence of reproductive chemical systems. As I have already implied, however, the very existence and effectiveness of natural selection depends strongly on the entire scaffolding of physical, chemical and biological processes which underpin the almost innumerable internested levels of order and dynamic organization represented by living systems and their supporting environments. Natural selection can only work on what has already emerged and prospered — and that presupposes the continuing successful operation of all the interacting networks of systems to which we have been referring. Once such sophisticated non-living systems have developed, a further advance involves their strategic separation from one another — and encapsulation — while at the same time remaining in continual mutually beneficial interaction with one another and with their environment — for energy, material resources, and waste disposal. An essential general feature of these systems is the prevalence of information- controlled feedback loops, which enable them to adjust continually to internal and external conditions, to maintain homeostasis and to assure their successful operation. Thus, even at this level there is what can be called teleonomic or goal-like behavior, which relies on selection and effective transmission of information crucial to the survival of the system. As a result the way these systems behave and evolve is radically context dependent (Küppers 1990, passim; Stoeger 1998, 177, and references therein). Thus, they manifest not only bottom-up and same-level causality, but also top-down causality — particularly because of the effective relationships their subsystems have with one another, and the system itself has with its environment. As these separated but interacting systems evolve, they form higher level systems with one another — manifesting co-operative and symbiotic behavior. This enables modularity and redundancy to develop — both in those systems that are living, and in those which are not. This is clear in eukaryotic cells and in multicellular animals, for instance. Each module of the system — e.g. the heart, the lungs, etc. — has its internal workings shielded from the rest of the organism. The organism itself does not need to monitor all those details, as long as the lungs are functioning properly. However, each module interacts with the organism in very specific ways, receiving nourishment and information from it for its successful operation, but also providing certain essential and very specific products or functions for the overall health and survival of the entire organism — in the case of the lung oxygen for the entire body. Natural selection continues to act on populations of these organisms or systems — enabling those which have emerged that are more fit for a given environment to flourish. We have briefly indicated here some of the key features which are involved in the emergence of more and more complex systems — and eventually living organ isms. What is absolutely necessary for this to occur are: 1. a basic underlying order (that is, physics and all that it presupposes), which as systems develop, leads to higher levels of order (chemistry and biology); 2. differentiation and diversity of systems — and therefore of their properties and capabilities; 3. evolving highly differentiated relationships among these entities and systems; 4. the effective generation, selection, preservation, reproduction, and co-ordinated implementation of information within and among systems and organisms. All these — particularly the internal and external constitutive relationships among lower-level components of systems and organisms — are at the basis of the phenomenon of emergence. They also obviously manifest a certain directionality — both the overall orientation towards certain outcomes, based on the conditions which obtain now and on the processes and relationships which dominate their continued operation and evolution, and the continuing drive to maintain themselves and their specific functioning within the larger systems of which they are a part. Thus, this directionality and functional teleology or teleonomy is deeply based in the laws of nature themselves — the regularities, processes and relationships which characterize our world. This is something I have always insisted upon, and which other specialists in this area have also stressed — for instance Paul Davies (1998, 151, and references therein) in his many writings. It is helpful to spend a few more minutes exploring how this functional teleology within systems can be explained. All the components needed have already been pointed out — and our brief discussion of the different levels of emergence in the next section will shed more light on what I am about to say. As we have already seen, as complexification proceeds — even long before living organisms emerge — there is a differentiation of structures (e.g. stars and planets, and the atoms and molecules of the different chemical elements and compounds) on many different levels. This automatically involves a differentiation of functions or capabilities — of the ways specific systems or structures interact or relate to others. Then these diverse systems — with different functions or specializations — evolve in their relationships and interactions, often forming symbiotic — mutually beneficial — more highly complex systems. This means that the specific function of each component eventually becomes not only beneficial to but also essential to the survival and successful operation of the larger more complex system. Each component thus fulfils a definite “purpose” within the larger system. In fact, each component has been selected because of what it gives the larger system. Natural selection is continually reinforcing and enhancing this choice — modifying it in light of what leads to more successful organisms (Ayala 1970, 1; 1998, 101). Thus, the particular fo cused outcome of each component or subsystem is why that component is present to begin with, and why it continues to play an essential role in the organism (Auletta, Ellis, and Jaeger 2007, 1159). Presupposing chemical, biological and physical compatibility and accessibility, as well as functional appropriateness, the “purpose” of each component emerges within the overall successful operation of the larger system of which it is a part. It fulfills a particular role within that system, which is essential to its life, development, or successful operation in its environment. This is how functional teleology arises — and how it flows from the underlying laws of nature which are operative at different levels in a complex system or an organism. 3. The different levels of emergence Not all types of emergence are equal — or even similar. Looking in more detail at the various general categories of emergence will aid us in appreciating and understanding how it occurs, and the role the important relationships among the components and within their environment play in constituting emergent systems as complex and novel. It will also enable us to understand how the distinctive selection and amplification processes that are often involved function, as well as the origin of the directionalities and functional teleologies which are implicit in them. Terrence Deacon (2006, 111; 2007, 88) has given us three general levels or orders of emergence, which are well worth considering. Deacon (2007, 93) defines emergent phenomena as those “having novel properties not contained in their constituent components and exhibiting regularities that cannot be deduced from laws affecting their constituents.” He goes on to stress, however, that at the same time the behavior and properties of emergent systems do not violate or replace the physical and chemical regularities and relationships governing the components. What is always critically important in emergent phenomena are, according to Deacon, the dynamical configurational regularities of the whole system which strongly affect — select, channel, reinforce and amplify — the constituent interactions. As Deacon (2007, 95) further comments: “What needs explaining is how some systems come to be dominated by higher-order causal properties such that they appear to ‘drag along’ component constituent dynamics, even though these higher-order regularities are constituted by lower-order interactions.” As already mentioned, the nonlinearities, positive and negative feedback loops, and selective amplification of certain lower-level and intermediate-level outcomes all play a central role in emergent systems and organisms. Deacon’s first-order emergence is exemplified by the pressure and temperature of a gas, or the surface tension and turbulent flow of liquids. These properties are not those of the individual molecules making up the gas or the liquid but are statistically based properties of large collections of such molecules. These emergent properties, however, can be understood and explained by the relationships among the molecules making up the gas or liquid — the statistical regularity of the relationships among the molecules leads to these emergent phenomena. The same is true of the emergence of galaxies or planetary systems, and at a higher level to emergence of the different chemical elements from more basic ones via fusion, or the production of chemical compounds like salt and water from their underlying chemical constituents. A helpful representative of second-order emergence is the growth of a snowflake. In this and other similar cases of emergence — leading to very unique and beautiful structures, or intricately organized, but non-living behaviors — the overall macroscopic configuration which begins to develop plays an essential role in constraining and guiding the microscopic processes which underlie the system, so that they are preferentially activated at some positions and not in others. This can be looked upon as selection of a few from a very large number of possibilities, and the amplification of the selected alternatives. In the case of the snowflake, prior growth sets the pattern for later growth. More advanced second-order emergent systems exhibit “autopoiesis” — dynamic self-organizing behavior. Chemical systems for instance can have several — or even many — different kinds of components which therefore interact very differently with one another but at the same time as part of interconnected cooperative network — as in the autocatalytic hypercycles (Eigen and Schuster 1978; Küppers 1983) to which we briefly referred above, or in the much simpler chemical oscillators (see, e.g. Peacocke 1983, 40 ff.) which so many have investigated over the past 50 years. Living systems — organisms — are the primary examples of third-order emergence. In this case, not only are “the higher-ordered states repeatedly re-entered into the lower-order dynamics,” as Deacon (2007, 106) is fond of saying, leading to reinforcement and amplification of those higher-order states, but there is also an ongoing cumulative memory and evolution of the living system across time, as the detailed information concerning the successful microscopic and macroscopic structures of the past are reintroduced in descendants of those systems. There is here very complex selection, reinforcement and in some cases amplification of earlier self-organizing systems and their slow or rapid evolution in slightly or even very different organisms via natural selection, symbiosis, etc. These are the principal levels of emergence Deacon has identified. George Ellis, a well-known physicist and cosmologist, has added others (Ellis 2006, 99) — such as those illustrated by learning in animals, and at even a higher level, by rational behaviour and the use of symbolic language in human beings. Again, all of them rely heavily on the complex, highly differentiated and dynamic relationalities among their constituents at many different levels of organization, and on innumerable deeply nested feedback control loops. These characteristics allow them to manifest the directionalities and functional finalities which we have already emphasized in our discussion. 4. Overarching teleology in nature and in the universe At this point we can briefly explore whether or not the natural sciences themselves provide evidence for an overall teleology — or finality — guiding or directing nature towards certain outcomes — or goals (Stoeger 1998, 182). From our discussions so far, is there any definite scientifically accessible way of reaching a conclusion on this issue? What about the anthropic principle, and the apparent fine-tuning of the universe it reveals? I am convinced that on the basis of our scientific findings so far, we have to conclude on strictly scientific grounds that there is no secure evidence of such a global finality. But, at the same time, there is also no scientific evidence ruling it out. On the one hand, it is clear that the physics and chemistry of our universe are open to the possibility of life and consciousness: We are here! Furthermore, as we have mentioned, slight changes in the underlying physics and chemistry would have rendered the universe completely sterile. So one might be led to suspect some deep cosmic purpose. But on the other hand, we know that there are vast numbers of cosmic venues where these possibilities have not been realized. In fact it may be — we shall probably never know — that we are the only location where intelligent life has emerged. This could lead to assuming that we are a happy accident — one of very few stellar systems, and one a very few universes where life and consciousness have arisen. Furthermore, there is the startling bleakness of the cosmic destiny which is provided by cosmology — it’s either freeze or fry. It now looks very much like it will be “freeze”! Science has no way of exploring the intentionality of agents which fall outside its investigative capabilities. Thus, we really cannot say one way or the other about an overarching teleology. On some philosophical grounds, and on theological grounds, of course, we can affirm such a teleology, or finality. The underlying order of the universe — not to mention its existence — requires an ultimate ground or basis, and almost certainly a radically relational basis. That ground or basis — the Creator — can be argued to have a definite purpose for ordering the universe is this way, rather than some other way. From Christian, Jewish and Islamic revelations intentional creation is central, and is motivated by the Creator’s love and desire to share the Creator’s existence and goodness with others, inviting them to share in full, free and loving communion with the Creator. We can compellingly argue this theologically. Though we cannot argue it scientifically — the Creator as Creator is inaccessible to the natural sciences — we can certainly say that all that we have found in the sciences supports a deep compatibility and consonance with our less inadequate understandings of the Divine. And, certainly, relationality-based emergence, along with the directionalities and focuses of local functional finalities at every level and the relative autonomy of nature, is at the core of this profound consonance.

  


W.R. Stoeger, “Emergence, directionality and finality in an evolutionary universe”, in G. Auletta, M. Leclerc, R.A. Martínez, Biological Evolution: Facts and Theories. A Critical Appraisal 150 Years after “The Origin of Species” (Rome: G&B Press, 2011), pp. 479-492.