by Gerald Schueler, Ph.D. © 1997
This paper addresses the thermodynamic concept of irreversibility in terms of living systems. The latest scientific findings on irreversibility are presented together with the concepts of time's arrows and time's cycles. The human psyche and ego, as defined by C.G. Jung, are considered to be complex living systems as described in modern chaos theory. Reasons are provided for viewing the psyche and ego as both autopoietic and dissipative structures. Entropy is discussed in terms of Clausius (classical entropy for closed systems), Prigogine (entropy for open systems), and Boltzmann (statistical entropy). The psyche's libido, defined by Jung as equivalent to the energy of classical physics, is shown to allow for reversible conditions for the ego. Two general types of reversibility are discussed: (1) regression as a pathological condition that expresses time's arrow, and (2) regression by means of introspection as a healthy technique that expresses time's cycle. The former usually results in a victim of mental illness, while the latter, when successful, is the primary task undertaken by the archetypal hero resulting in increased conscious control over forces in the unconscious.
Systems that change over time and whose processes cannot be traced backwards without leaving some sort of evidence, are said to be irreversible systems (Çambel, 1993). Reversible processes are those which can take place forward or backward over time; mathematically, changing time t in their equations to -t will have no effect. Most processes that real-life systems undergo are irreversible just as most complex systems (systems with numerous interrelated parts) are irreversible. According to the second law of thermodynamics, the entropy (a measure of disorder or chaos) of an isolated system (one that does not exchange matter, energy, or information with its environment) will remain unchanged for reversible processes but will increase for irreversible processes. Thus irreversible systems, including all living systems, tend to become chaotic as their entropy increases. Nicolis and Prigogine (1989) speak of a "universal role of irreversibility in nature" (p. 214) and point out that irreversibility of complex systems is not the result of "the complexity of the collective behavior of intrinsically simply objects" (p. 214) but rather is "due to the very structure of the dynamical systems" (p. 215).
Irreversibility of natural systems, including our universe, does not result from certainty, but rather from probability. Perceived events correspond to the evolution of the universe through successive states of increasing probability (Atkins, 1984). Two American chemists, Gilbert N. Lewis and M. Randall, summarized their findings by stating, "Every system which is left to itself will, on the average, change toward a condition of maximum probability" which can be paraphrased as "if you think things are mixed up now, just wait" (Angrist & Hepler, 1967, p. 159). According to Prigogine (1980) ""Irreversibility is the manifestation on a macroscopic scale of "randomness" on a microscopic scale" (p. 176).
Chaos theory views the future as a succession of probable events, and complex systems are attracted towards those possible states of maximum probability. Because complex systems, including living systems as well as our Earth itself, undergo irreversible processes over time, the temporal direction from past to the future is called time's arrow. "The essence of time's arrow lies in the irreversibility of history" (Gould, 1987, p. 194). The metaphor of time's cycles reflects nature's timeless laws rather than the contiguous moments of complex historical pathways. "Organisms follow time's arrow of contingent history; minerals, time's cycle of immanent geometrical logic." (Gould, 1987, p. 196). According to Gould (1987), Time's arrow and time's cycle join forces when we try to unravel nature's complexity.
Not only is our body a complex living system, but our ego as well. The Swiss psychologist, C.G. Jung, designated the ego as an ego-complex because of the numerous components and processes with which it is comprised. He taught that the components of the ego-complex are held together by the gravitational force of their relation to consciousness (Pascal, 1992).
The ego, the subject of consciousness, comes into existence as a complex quantity which is constituted partly by the inherited disposition (character constituents) and partly by unconsciously acquired impressions and their attendant phenomena ... Analytical psychology differs from experimental psychology in that ... it is far more concerned with the total manifestation of the psyche as a natural phenomenon - a highly complex structure. (Jung, 1954/1991, pp. 91- 92)
For Jung, the structure of the psyche, of which the ego is but one component, is not static but dynamic (Jacobi, 1973). It seems reasonable, then, to assume that the principles of chaos theory which relate to complex systems should be applicable to the ego and psyche as described by Jung.
A Brief Look at Entropy
Arthur Eddington called entropy, "time's arrow" (Angrist, p. 160). Entropy is an important concept in thermodynamics. The second law of thermodynamics defines entropy as a measure of needed energy. Entropy is a measure of a system's disorder. Entropy is also a measure of molecular randomness. Thus a solid has less entropy than a liquid, which has less than a gas (Angrist, 1967).
The inequality of Clausius, a corollary of the second law, states that any change in energy with respect to temperature must be less than, or equal to, zero. In other words, the energy of any system naturally tends to decrease. Mathematically we can say that,
ŠdQ / T # 0
where entropy, S, is defined for a reversible process as,
dS = dQ / T
Here S is called the Clausius's entropy after Rudolph Clausius, who first conceived the idea of entropy. For open systems (such as our bodies and the earth) the value of dQ will always be negative because energy always tends to leave such a system. The temperature of a planet, star, or galaxy tends to transfer toward the open spaces that surround it thereby producing a negative dQ. For such systems,
dSsystem $ -dQ / T
from which it can be demonstrated that
dSsystem + dSsurroundings $ 0
This equation expresses the principle of the increase of entropy. All processes in closed or isolated systems have increasing entropy. This is another way of saying that only those processes can naturally take place where entropy will increase. This is a law of closed-system thermodynamics. This law applies to all physical engines including our bodies and to all systems including our world when they are considered closed or isolated from their environments.
The general equation for an open system is,
dS $ dQ/T + dmisi - dmoso
As the mass dmi enters into the system, the entropy is increased by the amount dmisi. As the mass dmo leaves the system, the entropy is decreased by the amount dmoso. The existence of black holes, for example, could allow the entropy of a galaxy to decrease for a time, but only at the cost of decreasing the mass.
There are several other entropies in addition to that of Clausius. Prigogine's entropy, for example, addresses what is called far-from equilibrium thermodynamics which looks at nonlinear dynamic processes and self-organizing systems such as the cells of our body. The equation for Prigogine's entropy is:
where dST is the total entropy, dSI is the internal or Clausius' entropy, and dSE is the entropy exchanged with the surroundings (this term is zero for closed and isolated systems where Prigogine's entropy is identical to Clausius' entropy). While dSI tends to increase, the term dSE can increase or decrease or remain zero (it is positive if entropy enters the system and negative if entropy leaves the system). The important effect of Prigogine's entropy is that the total system entropy of an open system, dST, can be positive, negative, or zero. Systems for which dST < 0 (i.e., where entropy is decreasing) are said to be self-organizing (Çambel, 1993).
The second law of thermodynamics suggests that our entire universe is slowing down, because its entropy, its need for sustaining energy, is increasing. One of the results of this law is the prediction there that can be no perpetual motion machine. All systems wear down; energy is lost and cannot be totally recovered by a system. We can also consider entropy to be a measure of internal randomness, or molecular chaos. As entropy increases, chaos increases.
Prigogine's entropy implies that as systems become more complex, a threshold of complexity will be reached such that the system will begin functioning in unpredictable directions; such a system will lose its initial conditions and these can never be reversed or recovered (Briggs and Peat, 1989). For open systems where dSE is sufficiently negative that it exceeds the magnitude of dSI then entropy will decrease (order will increase) over time during the process, which could help explain the thermodynamics of dissipative systems (those that required energy from external sources) and self-organizing systems (such as all living systems) (Nicolis & Prigogine, 1989).
If we think of complex systems as being composed of millions of tiny subsystems (for example, the cells in our body, the citizens of a country, and the molecules in an object) then we will discover that each subsystem can act randomly while the overall system itself is in equilibrium and is relatively predictable. The theory of statistical mechanics, invented at the end of the last century, is one way of dealing with such subsystems. In this view, the system itself functions on the averages or probabalistic actions of its subsystems. For example, this is true for dissipative structures that are also autopoietic or self-organizing structures, which is to say, for living systems. Living systems maintain their dissipative structure by dissipating entropy before it has a chance to build up. Statistical entropy was created by the Austrian physicist, Ludwig Boltzmann. His equation is usually given as
S = -k E pi loge pi
where S is the entropy, pi is the probability of accessible states, and k is the Boltzmann constant. The higher the pi, the higher the entropy (Çambel, 1993). Boltzmann's entropy indicates that entropy will always tend towards a state of maximum probability (Lebowitz, 1993). In order to apply this equation, all of the accessible states must have the same probability of occurring (Fast, 1962).
When we view entropy as a measure of chaos, we can say that the probability of accessible states for any complex system is a measure of that system's uncertainty. Ludwig Boltzmann was the first to note that entropy is a measure of molecular disorder and he concluded that increasing entropy implied increasing disorder (Prigogine, 1980). Irreversible thermodynamics deals with systems that change over time, but it addresses only systems that are near to equilibrium conditions (Angrist, 1967).
Jung wrote prior to the discovery of Prigogine's entropy and thus was persuaded to regard the psyche as a "relatively closed system" in order to address the concept of entropy:
According to Boltzmann's formulation, this leveling process corresponds to a transition from an improbable to a probable state, whereby the possibility of further change is increasingly limited. Psychologically, we can see this process at work in the development of a lasting and relatively unchanging attitude. (Jung, 1928, p. 26)
For Jung, the psyche is governed by two important principles, entropy and the principle of equivalence. According to the principle of equivalence, any energy that is expended in one area of the psyche must appear in another area. Jung called the energy of the psyche the libido and described it as coursing through the psyche rendering its contents either conscious or unconscious. Jung (1956/1976) writes, "We can say, then, that the concept of libido in psychology has functionally the same significance as the concept of energy in physics" (p. 131). The principle of equivalence is similar to the law of the conservation of energy found in physics. The total amount of libido remains constant but pockets of it can ebb and flow at various places throughout the psyche. Jung viewed the psyche as an arena where polar opposites were continually being balanced. Forces at the higher end of the psyche, the spirit, were balanced by forces at the lower end of the psyche, the instincts:
The psyche is made up of processes whose energy springs from the equilibration of all kinds of opposites. The spirit/instinct antithesis is only one of the commonest formulations, but it has the advantage of reducing the greatest number of the most important and most complex psychic processes to a common denominator. So regarded, psychic processes seem to be balances of energy flowing between spirit and instinct. (Jung, 1947, p. 117)
A model of the psyche as the balancing of these two opposing energies is shown below.
This model shows the archetypes and instincts as polar opposites within the psyche. If the instincts are considered as subconscious, then the archetypes are superconscious. Between these psychic poles flows the libido charging and discharging various complexes, including the ego-complex, throughout the psyche.
For all complex systems, equilibrium represents maximum entropy. However, Darwin founded his theory of evolution on the principle that simple systems develop into complex systems over time. Darwinian evolution is just the opposite of what we would expect to find from the second law of thermodynamics (Prigogine & Stengers, 1984).
Evolution in Light of Chaos Theory
Living systems are open systems that thrive in far-from-equilibrium conditions. Open systems adjust to outside changes. They grow and replace themselves. They can usually survive the loss of their parts, unlike machines in a closed system. Their structures are dissipative so that they dissipate entropy and thus reduce chaos.
Dissipative structures maintain their structures by constantly dissipating entropy. Too much entropy "kills" a living system by bringing it into equilibrium and thus into stagnation. To dissipate entropy, systems must input energy and new materials which the system then uses to maintain its far-from-equilibrium conditions. Dissipative structures are not subject to the laws of closed-system thermodynamics. Their survival depends on becoming, and remaining, open systems. The very stability of dissipative structures depends on their being far from equilibrium. Their resistance to change is a result of their changing nature. However, such structures are highly dependent on their environment. Their independence is an illusion because they cannot, in fact, exist independently of their environment. Nicolis and Prigogine (1989) have extended the theory of dissipative structures to include dissipative systems--"systems that give rise to irreversible processes" (p. 50).
While some systems tend to run down, others are being created. Evolution is not a one-way flow wherein all systems grow in complexity, nor is it a one-way flow wherein all systems approach equilibrium. Evolution is a co-evolution, a sharing process that is made possible by continuous communication (Briggs & Peat, 1989).
An autopoietic structure, one that undergoes self-generation, is an animate or living dissipative structure. Evolution involves a process of material cooperation between living systems. Autopoietic structures are the result of a long series of cooperative exchanges; a holistic unfoldment, not simply an interaction of separate parts. Because our world and all living systems on it are open, Clausius' law of increasing entropy does not apply. So, while all living systems age in accordance with the second law of thermodynamics, "as time goes on there is also a broader and broader distribution of complexity, with the maximum complexity gradually increasing" (Gell-Mann, 1994, p. 235).
In chaos theory, systems changing over time are usually represented mathematically by evolution equations. These generally take the form of a series of differential equations that specify the rates of change of the system variables (Kellert, 1993). These systems undergo irreversible processes.
While the one-way aging of our body seems self-evident, psychology points out that our minds evolve and grow as well. According to Jung, our ego is "acquired" shortly after physical birth and develops over time much like the physical body. The ego "seems to rise in the first place from the collision between the somatic factor and the environment, and, once established as a subject, it goes on developing from further collisions with the outer world and the inner" (Jung, 1959/1978, p. 5). In this sense, the ego is a dissipative self-generating or autopoietic system.
The Arrow of Time
Complex systems are not reversible. All living systems are interwoven and none are truly reversible. Linear equations that represent system behavior suggest reversibility, but this is an illusion. Instability breaks up symmetry, which is never completely recovered. Nothing in our universe is truly reversible, although simple systems can be assumed to be reversible for all practical purposes.
Time flows in only one direction. The Arrow of Time points to irreversibility. For example, the Big Bang gives us an irreversible history. All things in our universe move through time from the Big Bang, where the physical universe began, to the end, which may be a Big Crunch, or simply a soupy nebulous sea of cold formless matter. According to Hawking (1988), there are three arrows of time: a thermodynamic arrow of time where entropy or disorder increases, a psychological arrow of time which allows us to remember a past but not a future, and a cosmological arrow of time in which our universe expands rather than contracts.
The entropy barrier is the name of a special limit for all complex systems. This barrier prevents complex systems, such as human beings, from going backward in time. Beyond this barrier, the path of a system is chaotic. Beyond a certain threshold of complexity, a system will go in unpredictable directions. They lose their initial conditions and cannot be reversed or recovered. Ultimately, this is a recognition of creative possibilities (Nicolis & Prigogine, 1989).
The unidirectional flow of time is suggested by the symbol of an arrow. This implies time's irreversibility. The past is fixed. The future is a world of possibilities, and therefore it is similar to the subatomic world of nuclear particles--both are probabalistic. Irreversibility is the state of becoming - but it is not a universal phenomenon.
There are numerous evolutions on-going, simultaneously over time, throughout the world, and their net effect is an overall constancy. In a very real sense, every dissipative structure undergoes its own unique evolutionary processes. Dissipative structures have coherence. The molecules of these systems each act as if they know the overall state of the system. "Irreversible processes play a fundamental constructive role in the physical world; they are at the basis of important coherent processes that appear with particular clarity on the biological level" (Prigogine, 1980, p. xiii). In far-from-equilibrium conditions, some equations that address microscopic interactions contain factors that address global characteristics. For example, the occurrence of dissipative structures requires that a system's size exceed some critical value. Prigogine (1980) concludes from this that "chemical instabilities involve long-range order through which the system acts as a whole" (p. 104).
An irreversible thermodynamic change is a change toward states of increasing probability. Reversible systems can be predicted. The future of irreversible systems (and all open systems are irreversible) cannot be predicted.
The idea of irreversibility should not be carried too far. If we are sick, we can recover our health and become well again. In some degree, after a period of aging, we often can regain our youth and our youthful vigor. But once we become an adult, we can never become a child again. While our physical body can sometimes be made to reverse its conditions and some of its characteristics, true reversibility, in the sense of actually going backward in time, is impossible.
The march of history through time is associated with a dichotomy. At one end is time's arrow, an irreversible sequence of unrepeated events. At the other end is time's cycle, where apparent motions through time are parts of repeating cycles, and differences of the past will be realities of the future. Time's arrow is causal while time's cycle is acausal (Gould, 1987). According to Gould (1987), the concept of arrows and cycles of time lies deep in Western thinking. They may even be archetypal.
Psychologists often divide the human lifespan into stages. Erickson, Freud, and Piaget, for example, have all described various developmental stages that we go through in serial order. Jung (1961/1989) describes three main stages or phases of life as: (1) the first years of life or presexual stage; (2) the second stage includes the years of childhood up to puberty; and (3) the third stage is the adult period from puberty on, and can be called the period of maturity. Harding (1947/1973) also describes three stages: (1) the naive which addresses the urge to self-preservation; (2) the ego stage which addresses the urge to sexuality and parenthood; and (3) the stage of consciousness of the Self which addresses the will to power. All of these stages are irreversible, because the human body itself is irreversible as it grows and matures from youth to old age. Although the ego is basically irreversible, it is possible to go backward in time. The human mind can revert to earlier stages in what is called regression.
Regression is the act of responding to a threatening situation in a way that is appropriate to an earlier age or level of development (Baron, 1989). It occurs when a person escapes anxiety by retreating into an earlier developmental stage that seems safer and less threatening (Darley, Glucksberg, & Kinchla, 1991). According to Jung,
A childish consciousness is always tied to father and mother, and is never by itself. Return to childhood is always the return to father and mother, to the whole burden of the psychic non-ego as represented by the parents, with its long and momentous history. Regression spells disintegration into our historical and hereditary determinants, and it is only with the greatest effort that we can free ourselves from their embrace. (Jung, 1974/1990, p. 136)
Harding (1947/1973) writes that in times of stress even "civilized individuals" can regress to an earlier mode of behavior (p. 97). In short, the ego has the ability to reverse to an earlier stage of development, but this reversal is usually not healthy, and often signifies a pathological escape from reality. It can occur unconsciously in both psychosis and neurosis, and if it is allowed to go too far, can result, for example, in deteriorated dementia praecox (Harding, 1947/1973). A partial regression can "throw the individual back into an earlier stage of development and create a neurosis, while in total regression consciousness is inundated by the contents of the unconscious and a psychosis occurs" (Jacobi, 1942/1973, p. 57). However, Jacobi (1942/1973) also notes that according to Jung, regression can have a positive value. "In the individual psyche regression may be a symptom of disturbance, but it can also be a way to restore balance and indeed to broaden the psyche" (Jacobi, 1942/1973, p. 58). This same process done consciously and deliberately, in the sense of "a voluntary encounter with the powers of the unconscious" is the task of the hero (Harding, 1947/1973, p. 288).
According to Jung (1967/1983), one aspect of the mythological dragon is "the initial state of unconsciousness" (p. 89). The hero represents "favorable action of the unconscious" while the dragon represents its "negative and unfavorable action" (Jung, 1956/1976, p. 374). It is the task of the hero to confront this dragon and slay it. "Unconsciousness has to be sacrificed; only then can one find the entrance into the head, and the way to conscious knowledge and understanding" (Jung, 1967/1983, p. 89). In myths, the hero is the one who conquers the dragon. The hero is able to assimilate the unconscious material, without falling victim to it (Jung, 1963/1989). In some motifs, the hero returns with a great treasure. "The treasure which the hero fetches from the dark cavern is life: it is himself, new-born from the dark maternal cave of the unconscious where he was stranded by the introversion or regression of libido" (Jung, 1956/1976, p. 374).
The hero is able to go backward in time by the processes of introversion or initiation (Harding, 1947/1973). He faces the "dragon" of his own past memories and conquers them through assimilation. The path taken by the insane is one of regression which fails to assimilate the experiences and fails to return. This route is an arrow of time, because the person becomes a victim of the regression and cannot properly assimilate the experiences nor make the return back to the present. Such a one becomes "lost" in their own past. On the other hand, the route taken by the hero is a cycle of time, because after experiencing the past there is a return to the present.
The renegade in man is closely related in its nature to the slothful aspect of the dragon, while the forward-going, heroic element in him is more nearly related to the energy of the dragon. Thus the human being who has conquered the dragon and assimilated its power through tasting its blood or eating its heart becomes a superman. He transcends the consciousness and therefore the powers of his contemporaries, because he has to this extent overcome the unconscious, which previously functioned, as it were, entirely outside the human psyche. (Harding, 1947/1973, p. 262)
By deliberately regressing consciousness into areas of the unconscious, and especially into the personal unconscious of Jung (1959/1990), we can broaden psychic life by bringing more of the unconscious into our conscious control. But to avoid madness, there must be a return to the present. This is the fundamental work of the archetypal hero.
Jung (1954/1985) suggested that introspection be carried out by the hero all the way back to early childhood and beyond so that "going beyond himself into the sphere of the collective psyche, he will enter first into the treasure-house of collective ideas and then into creativity" (p. 35). Jung (1953/1980) also warned of the danger of inflation, of being egocentric, and taught that "inflation is a regression of consciousness into unconsciousness. This always happens when consciousness takes on too many unconscious contents" (p. 481). The hero must therefore walk a narrow line. He must bring unconscious contents into consciousness, but not too many nor too often.
Jungian psychology views the ego as a subsystem within the overall system of the psyche. The psyche and ego, as defined by Carl Jung, are living systems composed of both autopoietic and dissipative structures. Both self-generate, function dynamically, and dissipate entropy while growing in complexity. However, unlike most complex dynamic systems, the ego is not entirely irreversible.
The difference between the archetypal hero and suffering victim could lie in the entropy barrier of the psyche, which is very likely to vary with each individual. Libido is the energy of the psyche. Decreased libido means increased entropy and chaos as consciousness sinks into the unconscious. As libido decreases, unconscious contents rise into consciousness and the ego sinks into a sea of images. This explains dreams, which are a normal functioning of the psyche. Sleep would seem to be one of the psyche's means for dissipating entropy and increasing libido.
Regression, as a pathological process, is the effect of an unusually large increase in entropy within the psyche. This could be caused by an increase in Boltzmann's probability of accessible states where a happier condition in the past (a remembered state space of the ego) becomes more and more accessible to the ego as the present becomes more and more unbearable. The increase in entropy causes a psychic imbalance as the ego approaches its entropy barrier. Functioning at this point becomes unpredictable. If the barrier is passed, return is difficult or impossible. The result is insanity. But if the barrier is not passed, and the ego is strong enough to return with full memory of the images observed, it returns as a hero.
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