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DTS - Schneider
Transcript of DTS - Schneider
ERIC D. SCHNEIDER and JAMES J. KAY Motivating the discussion: what do I hope to get from Dynamic Systems Theory? LIFE AS A MANIFESTATION OF THE SECOND LAW OF THERMODYNAMICS Jaegwon Kim’s Explanatory Exclusion Principle (EEP) Jaegwon Kim’s Explanatory Exclusion Principle (EEP): since two or more complete and independent causal explanations for the same event or phenomenon cannot exist, there can be only one complete and independent causal explanation of a given event or phenomenon.
Another version of the EEP: If a property F is causally sufficient for a property G, then no distinct property F* that supervenes on F causes G. Examples:
Homer’s causal overdetermination.
Monkey Intentions Richard Andersen’s (Caltech) research on neural encoding of intentions to act. Anderson and his colleagues made recordings from individual neurons in the pariental reach region (PRR_ of the motor cortex of monkeys. This region is known to encode intentions or higher-order plans to reach for specific targets, say a piece of fruit in a particular location. Andersen developed a program that correlated the monkey’s intentions to reach for specific goals, as revealed in their movements, with certain patterns in the recorded firings of neurons in their PRR. Using neural recordings, the program was able to predict with 67.5% accuracy the reaching behavior of the monkeys toward eight targets.
The neural signals that encode the monkeys’ intentions to reach for certain targets were recorded as averages of the firing rates (spikes per second) of individual neurons. But clears the same aggregate firing rate in a group of neurons is consistent with a lot of variation in the behavior of individual neurons. For example, very different temporal sequences of neural firings can give rise to the same firing rate. So an intention to reach for a certain target can be realized in many different ways at the level of individual neurons. Nonetheless, each intention is associated with a distinctive aggregate pattern of firing rates.
It is useful to introduce some simple notation. Suppose that the they monkeys can have intentions to reach for certain targets, I1, I2, I3, and so on, and can perform the corresponding actions A1, A2, A3, and so on. Suppose further that each intention Ii can be realized at the level of individual neurosn in different token patterns of neural firing, Ni1, Ni2, Ni3, and so on. Suppose that on some specific occasion a monkey forms the intention I1 to reach for a particular object and performs the corresponding action A1. Suppose further than N11 is the particular token pattern of neural firing that realizes or encodes the intention I1 on this occasion. The central question is: What was the cause of the monkey’s action A1? Was it the intention I1, or its particular neural realization N11? The exclusion principle dictates that the cause of the monkey’s action is the neural realization for the action A1, and by hypothesis I1 supervenes on N11, so the principle excludes I1 from being a cause, leaving N11 as the only possible cause.
From: “Nonreductive Physicalism and the Limits of the Exclusion Principle” by Christian List and Peter Menzies. (Journal of Philosophy Sept 2009) The concern here is that the macrophysical is causally inert. All the heavy lifting takes place on the micro level.
Smallism: the bricks of a wall are nothing but the bricks and mortar in a certain configuration. Indeed, it’s difficult to think of the wall as having any being apart from that which is found in its components. “The eeriness of dolls comes solely from the fact that they are completely modelled on human beings. They make us face the fear of being reduced to simple mechanisms and matter. In other words, they make us face the fear that fundamentally all humans belong to the void. Science seeking to unlock the secret of life also brought about this fear. The notion that nature can be calculated inevitably leads to the conclusion that humans too can be reduced to basic mechanical parts.”
Professor Luc Steel, director of Sony's Computer Science Laboratories in Paris: 'There is a danger in the field of viewing humans as machines, as automata, the way biology looks at humans as complex machines.' http://www.huffingtonpost.com/2010/01/10/roxxxy-sex-robot-photo-wo_n_417976.html Can Dualism help?
Ned Block candidly admits: We have no conception of our physical or functional nature that allows us to understand how it could explain our subjective experience . . . we have nothing – zilch – worthy of being called a research programme, nor are there any substantive proposals about how to go about starting one . . . Researchers are stumped.
John Heil: 'In recent years, dissatisfaction with materialist assumptions has led to a revival of interest
in forms of dualism.'
Dualism Can’t help. We don’t know what an intention or agent is. When we try to think about it, we can’t help but imagine it as a kind of ghostly cause—an uncaused caused which, while it can affect the world, has no substance.
Chisholm in “Human Freedom and the Self”: The concept is subject to a difficulty which has long been associated with that of the prime mover unmoved. We have said that there must be some event A, presumably some cerebral event, which is caused not by any other event, but by the agent. Since A was not caused by any other event, then the agent himself cannot be said to have undergone any change or produced any other event (such as 'an act of will' or the like) which brought A about. But if, when the agent made A happen, there was no event involved other than A itself, no event which could be described as making A happen, what did the agent's causation consist of? What, for example, is the difference between A's just happening, and the agents' causing A to happen? We cannot attribute the difference to any event that took place within the agent. But Scientific Naturalism is equally unpalatable.
Robert Hanna writes in Kant, Science and Human Nature (pp 13-14):
Scientific or reductive naturalism says (a) that reality is ultimately whatever the exact sciences tell us it is; (b) that all properties and facts in the real world are ultimately nothing over and above fundamental or first-order physical properties and facts; and (c) that all knowledge is at bottom empirical. If scientific or reductive naturalism is true, then its implications are stark and profound: nothing is ultimately or irreducibly mental, first-personal, or subjective; nothing is ultimately or irreducibly semantic; nothing is ultimately or irreducibly abstract or universal; nothing is ultimately or irreducibly modal; nothing is ultimately or irreducibly logical; nothing is ultimately or irreducibly a priori; nothing is ultimately or irreducibly normative; nothing is ultimately or irreducibly free or autonomous; and nothing is ultimately or irreducibly moral. We’ve been focusing on the Explanatory Exclusion Problem as it applies to us—the mind problem. How can there be agentive causation if our behavior is completely accountable by way of microphysical event causation?
But it is important to see that if EEP is correct, we’ve lost a lot more than our ability causally affect the world. Any microphysical system can be so causally reduced. It’s not heat that caused the water to boil, but molecular kinetic energy.
It’s not the hurricane that destroyed New Orleans, but a confluence of microphysical interactions.
What is causing global warming? Us or volcanic eruptions (or solar cycles…)? NIETHER! Global warming is caused by microphysical systems. “Volcano” is a logical fiction which is exhausted by a configuration of subatomic particles (or simples, or stings…) in a certain relation.
Hackers swipe millions of dollars worth of carbon credit swaps. Der Spiegel reports that hackers obtained unauthorized access to online accounts where companies maintain carbon credits, and stole around $4 million worth of carbon credits. "At least seven out of 2,000 German firms that were targeted in the phishing scam fell for it. One of these unidentified firms reportedly lost $2.1 million in credits in the fraud."
What caused the industrial revolution?
What caused the decrease in violent crime during the late 1990’s? Notice that the appeal to dualism—even if it solves the problem of agentive action—doesn’t solve the microphysical Causal Exclusion Problem. Believe it if you can. What I mean is that the philosophical price of scientific or reductive naturalism is precisely the “disenchantment of nature”, and the disenchantment of human nature too, as artistically imagined, for example, at the turn of the nineteenth century by Heinrich Kleist in his gothic horror story Über das Marionettentheater, and again at the turn of the twentieth century by Robert Musil in the guise of his ironically presented and profoundly alienated anti-hero Ulrich, “the Man Without Qualities.” Essentially the same worry is vividly expressed by Wittgenstein when he considers the possibility that in creating a world culture based on the search for exact scientific knowledge of the physical world, humanity is regressing towards cognitive and ethical suicide. In any case, it is entirely clear that if scientific or reductive naturalism is true, then the manifest image of human beings and their world is both explanatorily and ontologically reducible to the scientific image. Or, more starkly put, it is entirely clear that if scientific or reductive naturalism is true, then we are nothing but naturally mechanized puppets epiphenomenally dreaming that we are real persons. And that seems to me, as it seemed to Kleist, Musil, and Wittgenstein, philosophically tragic. It also seemed philosophically tragic to Kant: Introduction to Schneider and Kay Erwin Schrödinger - What is Life?
Life is composed of two processes:
"order from order": Biological reproduction by way of a coding system (DNA)
"order from disorder": This was an effort to link biology with the fundamental theorems of thermodynamics. Problem: The second law of thermodynamics insists that, within closed systems, entropy should be maximized and disorder should reign.
Living systems, however, are the antithesis of such disorder. They display marvelous levels of order created from disorder. How to solve this:
Schrödinger: nonequilibrium thermodynamics. Living systems exist in a world of energy and material fluxes. An organism stays alive in its highly organized state by taking energy from outside itself, from a larger encompassing system, and processing it to produce, within itself, a lower entropy, more organized state
Life is a a far from equilibrium system that maintains its local level of organization at the expense of the larger global entropy budget.
This is an attempt to reconcile biological self-organization and thermodynamics. Schneider and Kay attempt to build on Schrödinger’s suggestion: “This work harmonizes physics and biology at the macro level and shows that biology is not an exception to physics, we have simply misunderstood the rules of physics.”
Restate/generalize the 2nd law of thermodynamics.
Illustrate the imperative to dissolve gradients of energy by way of a simple physical example: Bénard Cells
Apply findings to more complex dissipative thermodynamic structures: weather systems, life, and whole ecosystems. The Second Law of Thermodynamics First law of thermodynamics: energy cannot be created or destroyed—only transformed.
Second law of thermodynamics (classically stated): physical or chemical processes lead to a reduction in the overall quality of energy.
Entropy is the measure of irreversibility.
Any real process can only precede in a direction which results in an entropy increase. Nature inevitably becomes more random. If the universe is a closed system, it will eventually achieve Global thermodynamic equilibrium (GTE), where the temperature will become homogeneous throughout the whole system. This is “heat death”.
Wikipedia: The heat death is a possible final thermodynamic state of the universe, in which it has "run down" to a state of no thermodynamic free energy to sustain motion or life. In physical terms, it has reached maximum entropy. This is a state where all energy is evenly distributed. Recent observations suggest that the expansion of the universe will continue forever. If so, the universe will cool as it expands, eventually becoming too cold to sustain life. For this reason, this future scenario is popularly called the Big Freeze.
The future of an expanding universe is bleak. If a cosmological constant accelerates the expansion of the universe, clusters of galaxies will rapidly be driven away from each other untill all galaxies are receding from their nearest neighbours at velocities greater than the speed of light, leaving observers in different clusters unable to either reach each other or sense each other's presence in any way. Stars are expected to form normally for 1 × 1012 to 1 × 1014 years, but eventually the supply of gas needed for star formation will be exhausted. Once the last star has exhausted its fuel, stars will cease to shine. The stellar remnants left behind are expected to disappear as their protons decay, leaving behind only black holes which themselves eventually disappear as they emit Hawking radiation.
After all the black holes have evaporated (and after all the ordinary matter made of protons has disintegrated, if protons are unstable), the universe will be nearly empty. Photons, neutrinos, electrons, and positrons will fly from place to place, hardly ever encountering each other. Ultimately, if the universe reaches a state in which the temperature approaches a uniform value, no further work will be possible, resulting in a final heat death of the universe. RIP Extended second law of thermodynamics Limitation of the classical laws: they don’t account for the behavior of systems which are open (to energy flows) and reside at stable states some distance from equilibrium. Such systems can maintain themselves for a period of time away from thermodynamic equilibrium in a locally reduced entropy steady-state.
Ex: black hole Properties of these steady state systems:
The steady states are achieved at the cost of increasing the entropy of the larger "global" system in which the dissipative structure is embedded. (This explains why evolution is not in contradiction with the 2nd law, classically stated.)
Such systems are dependent on outside energy fluxes to maintain their organization in a locally reduced entropy state.
And such system will resist being removed from the local-equilibrium state by way of “gradients” imposed on the system. The restated second law of thermodynamics: "The thermodynamic principle which governs the behaviour of systems is that, as they are moved away from equilibrium, they will utilize all avenues available to counter the applied gradients. As the applied gradients increase, so does the system's ability to oppose further movement from equilibrium."
In other words, a steady state system is one which aims toward gradient destruction. This is why these systems are called dissipative structures (they dissipate gradients). These “nonequilibrium” systems may be said to achieve local thermodynamic equilibrium. Example of a dissipative structure: Bénard Cells Initially all dissipation of heat through the fluid occurs via conduction and molecule to molecule interaction. (Note that this process is fully describable in terms of microphysical interaction)
When the gradient reaches a critical level (Rayleighnumber1760) the transition to highly organized convection occurs. These convective structures result in highly structured coherent hexagonal surface patterns (Bénard Cells) in the fluids. Due to the convective overturn most of the working fluid in the container becomes vertically isothermal (with little gradient) and only the boundary layers on the edge of the system carry the gradient. As the gradient is increased the boundary layers become thinner and more dissipation occurs.
Importantly: As the gradient increases, a greater amount of work must be done to incrementally increase the gradient. It become more difficult to maintain the gradient as the system gets more organized. The further from equilibrium that the system is, the more it resists being moved further from equilibrium. This is a simple physical system: new, organized structures emerge which better resist the application of an external gradient (in this case, heat). Bénard Cells are “dissipative structures”: they are structures which aim to dissipate energy gradients. Other examples:
Tornado in a bottle.
Without outside gradient: six minutes.
The experiment is then repeated with the bottles being given a slight rotational perturbation. A vortex forms, driven by the gravitational gradient within the system, and drains the upper bottle in approximately 11 seconds. The "tornado", a highly organized structure, has the ability to dissipate the gradient much faster thus bringing the system to its local equilibrium more quickly! Weather patterns:
The development of temperature gradients between a warm earth and a cooler overlying atmosphere (and the equator and the poles) results in highly organized convective cloud patterns which reduce the troposphere temperature gradient.
Also Chemical Systems.
Chemical gradients result in dissipative autocatalytic reactions, examples of which are found in
1)simple inorganic chemical systems,
2)in protein synthesis reactions, or
5)hydrolytic autocatalytic reactions. (Kauffman, At Home in the Universe). Living Systems and the ecosystem: sophisticated dissipative structures The earth’s principle energy gradient: the sun.
Living systems are open and not the adiabatic closed boxes of classical thermodynamics. An organism stays alive in its highly organized state by taking energy from outside itself, that is from a larger encompassing system, and processing it to produce a lower entropy state within itself. Life can be viewed as a far-from-equilibrium dissipative structure that maintains its local level of organization, at the expense of producing entropy in the larger system it is part of.
We suggest that living systems are dynamic dissipative systems with encoded memories, the gene with its DNA, that allow the dissipative processes to continue without having to restart the dissipative process via stochastic events. Living systems are sophisticated mini-tornados, with a memory (its DNA).
The origin of life should not be seen as an isolated event. Rather it represents the emergence of yet another class of processes whose goal is the dissipation of thermodynamic gradients. Life should be viewed as the most sophisticated (until now) end in the continuum of development of natural dissipative structures from physical to chemical to autocatalytic to living systems.
Biological growth occurs when the system adds more of the same types of pathways for degrading imposed gradients. Biological development occurs when new types of pathways for degrading imposed gradients emerge in the system. Ecosystems display the influence of thermodynamic principles in their patterns of growth and development. A thermodynamically based theory of ecology holds the promise of propelling ecology from a descriptive to a predictive science. Ecosystems are the result of the biotic, physical, and chemical components of nature acting together as a nonequilibrium dissipative process. As such ecosystem development increases energy degradation thus following the imperative of the second law. The authors provide empirical support for this. If an ecosystem is a dissipative steady state structure which aim to counter an imposed gradient then the following should hold:
More energy capture
More energy flow within the system.
More cycling of energy
Higher trophic structure.
Higher respiration and transpiration
Larger ecosystem biomass
More types of organisms (increases the diversity of pathways for degrading energy).
All of these should increase energy dissipation. Environmental degradation reduces dissipative capacity of an ecosystem. This may be the basis for the Gaia hypothesis. Questions Dissipation of an applied gradient is explicitly treated as an Aristotelian or purpose. The authors rank entities according to their capacity to increase energy degradation.
We provide biology with a paradigm that not only describes the "why" of life but also describes the directions in which living systems will develop and evolve.
We suggest that living systems are dynamic dissipative systems with encoded memories, the gene with its DNA, that allow the dissipative processes to continue without having to restart the dissipative process via stochastic events. Living systems are sophisticated mini-tornados, with a memory (its DNA), whose Aristotelian "final cause" may be the second law of thermodynamics.
We have documented that ecological processes are driven and governed by thermodynamic imperatives; ecosystems develop and select energetic pathways that strive to degrade as much of the energy available to them as possible.
Is this plausible? Does life aim at energy dissipation? Why? Related: What is the relation between this picture of life (as an advanced dissipative structure) and that of Darwin’s?
How can we reconcile the imperative to degrade energy and the imperative to survive?
Note that this is the authors’ own language: Life represents a balance between the imperatives of survival and energy degradation.
They fall back on a tapestry metaphor.
"I like to compare evolution to the weaving of a great tapestry.
The strong unyielding warp of this tapestry is formed by the essential nature of elementary non-living matter, and the way in which this matter has been brought together in the evolution of our planet. In building this warp the second law of thermodynamics has played a predominant role.
The multi¬colored woof which forms the detail of the tapestry I like to think of as having been woven onto the warp principally by mutation and natural selection.
While the warp establishes the dimensions and supports the whole, it is the woof that most intrigues the aesthetic sense of the student of organic evolution, showing as it does the beauty and variety of fitness of organisms to their environment. But why should we pay so little attention to the warp, which is after all a basic part of the whole structure? Perhaps the analogy would be more complete if something were introduced that is occasionally seen in textiles-the active participation of the warp in the pattern itself. Only then, I think, does one grasp the full significance of the analogy."
Schrödinger gives an answer: life is comprised of two processes, "order from order, and order from disorder". But reproduction by way of DNA isn’t the same as Darwinian evolution. After all, and IDer could grant the former while denying the latter. DNA is memory and allows order to be made from existing order. But both the imperative to life and the imperative to dissipation explain how something becomes orderly in the first place. Finally, how might this answer Kim’s explanatory exclusion principle?
What we get with dissipative structures is a level of organization which can’t be described when we confine ourselves to the behiavor of microstructures. Both conduction and convection work by way of the same microphysical principles: rapidly moving or vibrating atoms and molecules interact with neighboring atoms and molecules, transferring some of their energy (heat) to these neighboring atoms.
But convection entails the combined effects of conduction and fluid flow. The important thing is, unlike forced convection (where an e.g. fan is used to move the fluid), the fluid flow is a result of a self-organizing process which results from the application of a gradient alone.
My hope is that this model will give us a reason to think that reductive physicalism is false, because is can’t adequately characterize these macrophysical processes. This becomes all the more intriguing when we realize that we are one such process. http://www.myvideo.de/watch/1183791/Convection_in_granular_media_slow_version What I Learned From Reading Every Last Word of India Today (NYT)
9. The All India Council for Technical Education has the following ambitions: “Entropy in the Universe should rise indicating that the well-being of the Universe is improving. If I can contribute to the well-being of our society and make an addition to the entropy, I am happy. . . An anonymous reader writes "A single equation grounded in basic physics principles could describe intelligence and stimulate new insights in fields as diverse as finance and robotics, according to new research, reports Inside Science. Recent work in cosmology has suggested that universes that produce more entropy (or disorder) over their lifetimes tend to have more favorable properties for the existence of intelligent beings such as ourselves. A new study (pdf) in the journal Physical Review Letters led by Harvard and MIT physicist Alex Wissner-Gross suggests that this tentative connection between entropy production and intelligence may in fact go far deeper. In the new study, Dr. Wissner-Gross shows that remarkably sophisticated human-like "cognitive" behaviors such as upright walking, tool use, and even social cooperation (video) spontaneously result from a newly identified thermodynamic process that maximizes entropy production over periods of time much shorter than universe lifetimes, suggesting a potential cosmology-inspired path towards general artificial intelligence."