"Living systems are integrated wholes whose properties cannot be reduced to those of smaller parts. Their essential, or "systemic," properties are properties of the whole, which none of the parts have. They arise from the "organizing relations" of the parts—that is, from a configuration of ordered relationships that is characteristic of that particular class of organisms, or systems. Systemic properties are destroyed when a system is dissected into isolate elements."
pg. 36
"Another key criterion of systems thinking is the ability to shift one's attention back and forth between systems levels. Throughout the living world we find systems nesting within other systems, and by applying the same concepts to different systems levels—for example, the concepts of stress to an organism, a city, or an economy—we can often gain important insights. On the other hand, we also have to recognize that, in general, different systems levels represent levels of differing complexity. At each level the observed phenomena exhibit properties that do not exist at lower levels. The systemic properties of a particular level are called "emergent" properties, since they emerge at that particular level."
"Ultimately—as quantum physics showed so dramatically—there are no parts at all. What we call a part is merely a pattern in an inseparable web of relationships. Therefore the shift from the parts to the whole can be seen as a shift from objects to relationships. In a sense, this is a figure/ground shift. In the mechanistic view the world is a collection of objects. These, of course, interact with one another, and hence there are relationships among them. But the relationships are secondary. . . In the systems view we realize that the objects themselves are networks of relationships, embedded in larger networks. For the systems thinker the relationships are primary. The boundaries of the discernible patterns ("objects") are secondary. . ."
pg. 37
"Whereas Newtonian mechanics was a science of forces and trajectories, evolutionary thinking—thinking in terms of change, growth, and development—required a new science of complexity. The first formulation of this new science was classical thermodynamics with its celebrated "second law," the law of dissipation of energy. According to the second law of thermodynamics, formulated first by the French physicist Sadi Carnot in terms of the technology of thermal engines, there is a trend in physical phenomena from order to disorder. Any isolate, or "closed," physical system will proceed spontaneously in the direction of ever-increasing disorder.
To express this direction in the evolution of physical systems in precise mathematical form, physicists introduced a new quantity call "entropy." According to the second law, the entropy of a closed physical system will keep increasing, and because this evolution is accompanied by increasing disorder, entropy can be seen as a measure of disorder."
pg. 47
"All major achievements of cybernetic originated in comparisons between organisms and machines—in other words, in mechanistic models of living systems. However, the cybernetic machines are very different from Descartes's clockworks. The crucial difference is embodied in Norbert Wiener's concept of feedback and is expressed in the very meaning of "cybernetics." A feedback loop is a circular arrangement of casually connected elements, in which an initial cause propagates around the links of the loop, so that each element has an effect on the next, until the last "feeds back" the effect into the first element of the cycle. The consequence of this arrangement is that the first link ("input") is affected by the last ("output"), which results in self-regulation of the entire system, as the initial effect is modified each time it travels around the cycle."
pg. 56
""The circular causality in a feedback loop does not imply the elements in the corresponding physical system are arranged in a circle. Feedback loops are abstract patterns of relationships embedded in physical structures or in the activities of living organisms. For the first time in the history of systems thinking, the cyberneticists clearly distinguished the pattern of organization of a system from its physical structure—a distinction that is crucial to the contemporary theory of living systems."
pg. 64
"The human nervous system does not process any information (in the sense of discrete elements existing ready-made in the outside world, to be picked up by the cognitive system), but interacts with the environment by continually modulating its structure. . .Our thinking is always accompanied by bodily sensations and processes."
pg. 68
"We have seen that throughout the history of Western science and philosophy there has been a tension between the study of substance and the study of form. The study of substance starts with the question, What is it made of?; the study of form with the question, What is its pattern? These are two very different approaches, which have been in competition with one another throughout our scientific and philosophical tradition."
pg. 80
"...the key to a comprehensive theory of living systems lies in the synthesis of those two very different approaches, the study of substance (or structure) and the study of form (or pattern). In the study of structure we measure and weigh things. Patterns, however, cannot be measured or weighed; they must be mapped. To understand a pattern we must map a configuration of relationships."
"What is destroyed when a living organism is dissected is its pattern. The components are still there, but the configuration of relationships among them—the pattern—is destroyed, and thus the organism dies."
pg. 81
"[Heinz von Foerster] coined the phrase 'order from noise' to indicate that a self-organizing system does not just 'import' order from its environment, but takes in energy-rich matter, integrates it into its own structure, and thereby increases its internal order."
pg. 84
"Summarizing those three characteristics of self-organizing systems, we can say that self-organization is the spontaneous emergence of new structures and new forms of behavior in open systems far from equilibrium, characterized by internal feedback loops and described mathematically by nonlinear equations."
pg. 85
"...'Benard Cells' showed that as the system moves farther away from equilibrium (that is, from a state with uniform temperature throughout the liquid), it reaches a critical point of instability, at which the ordered hexagonal pattern emerges."
pg. 87
"Hypercycles turn out to be not only remarkably stable, but also capable of self-replication and of correcting replication errors, which means that they can conserve and transmit complex information. Eigen's theory shows that such self-replication—which is, of course, well-known for living organisms—may have occurred in chemical systems before the emergence of life, before the formation of genetic structure. . . The lesson to be learned here seems to be that the roots of life reach down into the realm of nonliving matter.
One of the most striking lifelike properties of hypercycles is that they can evolve by passing through instabilities and creating successively higher levels of organization that are characterized by increasing diversity and richness of components and structures. . . ...Eigen made the revolutionary step of using a Darwinian appraoch to describe evolutionary phenomena at a prebiological, molecular level."
pg. 94
"While organismic biologists had explored the nature of biological forms, cyberneticists had attempted to understand the nature of the mind. Maturana realized in the late sixties that the key to both of these puzzles lay in the understanding of "the organization of the living."
pg. 96
"According to Maturana, perception and, or more generally, cognition do not represent an external reality, but rather specify one through the nervous system's process of circular organization. From this premise Maturana then took the radical step of postulating that the process of circular organization itself—with our without a nervous system—is identical to the process of cognition..."
pg. 97
autopoiesis "self-making":
"It is a network of production processes, in which the function of each component is to participate in the production or transformation of other components in the network. In this way the entire network continually 'makes itself.' It is produced by its components and in turn produces those components. 'In a living system,' the authors explain, 'the product of its operation is its own organization.
An important characteristic of living systems is that their autopoietic organization includes the creation of a boundary that specifies the domain of the network's operations and defines the system as a unit. The authors point out that catalytic cycles, in particular, do not constitute living systems, because their boundary is determined by factors (such as a physical container) that are independent of catalytic processes."
pg.98-99
"...there is complete chemical equilibrium in the Martian atmosphere. . . ...Lovelock recognized the Earth's atmosphere as an open system, far from equilibrium, characterized by a constant flow of energy and matter."
pg. 102
"[Lynn] Margulis had no problem answering Lovelock's many questions about the biological origins of atmospheric gases, while [James] Lovelock contributed concepts from chemistry, thermodynamics, and cybernetics to the emerging Gaia theory. Thus the two scientists were able gradually to identify a complex network of feedback loops that—so they hypothesized—bring about the self-regulation of the planetary system.
The outstanding feature of these feedback loops is that they link together living and nonliving systems. We can no longer think of rock, animals, and plants as being separate. Gaia theory shows that there is a tight interlocking between the planet's living parts—plants, microorganisms. and animals—and its nonliving parts—rocks, oceans , and the atmosphere."
pg. 104
"Indeed, the image of Gaia as a sentient being was the main implicit argument for the rejection of the Gaia hypothesis after its publication. Scientists expressed it by claiming that the hypothesis was unscientific because it was teleological—that is, implying the idea of natural processes being shaped by a purpose. 'Neither Lynn Margulis nor I have ever proposed that planetary self-regulation is purposeful,' Lovelock protests, 'Yet we have met persistent, almost dogmatic, criticism that our hypothesis is teleological.'"
pg. 107
"Feedback loops that link environmental influences to the growth of daisies, which in turn affect the environment, are an essential feature of the Daisyworld model. When this cycle is broken so that there is no influence of the daises on the environment, the daisy populations fluctuate wildly and the whole systems goes chaotic. But as soon as the loops are closed by linking the daisies back to the environment, the model stabilizes and self-regulation occurs."
pg. 110
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