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…taking things apart in thought…as a way to investigate their normal integrity.
The word science comes from the Latin scientia (knowledge), which in turn comes from an Indo-European root that means to cut apart, separate, discern (cf. French, scier.) The term scientist did not come into use until the 1830s, prior to which scientists were called natural philosophers. George Sarton defines science as “systematized positive knowledge”—indeed, as the only human activity that is “truly cumulative and progressive” [The Study of the History of Science Dover 1936/1957, p5] He qualifies this by continuing: “The scientist of philosophic mind is not interested so much in the latest results of science as he is in its eternal tendencies, in the living and exuberant and immortal tree. The fruits of today may be tempting enough, but they are not more precious to his way of thinking than those of yesterday or tomorrow.” Yet, this timelessness seems to contradict the cumulative, progressive aspect, and may reflect more the attitude of the historian or philosopher than the practicing scientist.
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As a consequence, there is both a public and a private scientific narrative.
Historian of science Gerald Holton distinguishes between the formalized finished products of scientific thought—as presented in published research papers—and its earlier formative stage: private versus public science. For example: “For quite good reasons—to arrive more dispassionately at consensus—modern scientists try to keep their personal struggles out of their published research results and out of their textbooks.” [Holton Einstein, History, and Other Passions , p78] Yet these struggles are revealed in personal papers and correspondence. Also: “Codified science is successful exactly in so far as it is indeed indifferent to human enjoyment and concerns; but the very opposite is true of the individual investigator. His creativity depends on a complete interpenetration of his person and his work. His dedication may spring from some nonrational, mystical, or religious conviction which was often acknowledged in other years when scientists were freer with their personal secrets.” [Holton Thematic Origins of Scientific Thought, P407]
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In contrast, the new science of dynamics became the general analysis of change over time: efficient cause became the normal order.
The ‘normal order of things’ corresponds in modern terms to the state of a physical system and its behavior in the absence outside influence. Efficient cause would then be an outside force that changes the state of the system. Such an analysis goes hand in hand with the concept of the isolated system. Aristotle’s thinking is more compatible with a holistic approach in which there are no isolated systems.
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…force is physical rather than the influence of some “motive intelligence.
Like Newton later, Kepler first speculated (that the gravitational force might fall off as the square of the distance, but rejected this idea because he assumed the force is exerted only in the plane of revolution—i.e. only in a direct line between orbiting objects. This may indicate that he had not entirely abandoned the notion of motive force, exerted intentionally in a direction, rather than radiating in a purely mechanical fashion.
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Time analysis reflects the shift…to the new science of dynamics.
Cf. Reginald Cahill “Process Physics”, Process Studies supplement 2003 p57: “Like space the phenomenon of time eventually became synonymous with its geometrical model until today most physicists regard time as a geometrical phenomenon, which of course necessitates the denial of any aspects of time that the geometrical model cannot accommodate.”
Apart from its military uses, one may speculate that the interest in dynamics and time reflected the millennial preoccupations of medieval Christendom, and more generally the linear time of literate cultures, especially in the Judaic tradition.
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He prefers to let nature speak for itself…a more direct transcription of natural fact.
“…for that is the true philosophy which echoes most faithfully the voices of the world itself, and is written as it were at the world’s own dictation; being nothing else than the image and reflexion thereof, to which it adds nothing of its own , but only iterates and gives back.” [Bacon Great Instauration 1857-74:4.327] On the other hand: “we will have it that all things are as in our folly we think they should be, not as seems fittest to the Divine wisdom, or as they are found to be in fact… But we clearly impress the stamp of our own image on the creatures and works of God, instead of carefully examining and recognizing in them the stamp of the Creator himself.” [5.132]
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…Newton himself disclaimed the notion of action at a distance that became associated with him.
Following Copernicus and Kepler, Newton retains the Aristotelian notion of motion towards the center, only the center is now no longer the absolute center of the universe, but the center of any “mass” concerned. The motion is now no longer considered “natural,” but caused by an unspecified “force.” He relates the accelerated motion of planets to the accelerated motions of terrestrial things caused by applied contact forces, but declines to say how such forces can be transmitted across empty space: “I refer the motive force to the body as an endeavor and propensity of the whole towards a center… endued with some cause, without which those motive forces would not be propagated through spaces round about, whether that cause be some central body (such as the magnet in the center of the magnetic force, or the earth in the center of the gravitating force), or anything else that does not yet appear. For I here design only to give a mathematical notion of those forces without considering their physical causes and seats.” [Newton, Principia Def VIII.]
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As a form of cognition, science focuses on what it presumes to exist independent of cognition.
This paradox leads to what I call the Problem of Cognitive Domains: how one logical level is recycled as the basis from which it is supposedly derived. On the other hand, Andrew Pickering disputes that science is a form of cognition: “The modern sciences invite us to imagine that our relation to the world is basically a cognitive one… and that, conversely, the world is just such a place that can be known through the methods and in the idiom of the modern sciences.” [Pickering The Cybernetic Brain: sketches of another future U. of Chicago Press 2010, p20-21] He contrasts the ideal of representative knowledge with that of cybernetics: effective performance in the world. From that perspective, science (like consciousness) pursues a “cognitive detour” (or “representational detour”) from a course of action that is naturally more direct.
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Instrumentation extends the senses…and also objectifies the properties to which it responds.
For example, ‘temperature’ originally referred to heat sensation, but was quantitatively defined as a property of matter that could give rise to that sensation. In this way it could be measured objectively rather than subjectively, using the response of mercury to heating, for example, rather than the response of the body. When the limiting properties of mercury were discovered, temperature was again redefined, in terms of the absolute thermodynamic scale. An historically later concept took precedence as the logically prior definition. [Max Jammer Concepts of Force Harvard UP 1957, p6]
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…it selects…phenomena that can be isolated to depend on relatively few factors.
Cf. Eugene Wigner “The Unreasonable Effectiveness of mathematics in the Natural Sciences” 1960: “Again, it is true that if there were no phenomena which are independent of all but a manageably small set of conditions, physics would be impossible… All the laws of nature are conditional statements which permit a prediction of some future events on the basis of the knowledge of the present, except that… the overwhelming majority of the determinants of the present state of the world… are irrelevant from the point of view of the prediction.”
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…sometimes losing sight of the broader goal of “understanding” nature.
Cf. John Bell, Against Measurement ibid: “In the beginning natural philosophers tried to understand the world around them. Trying to do that they hit upon the great idea of contriving artificially simple situations in which the number of factors involved is reduced to a minimum. Divide and conquer. Experimental science was born. But experiment is a tool. The aim remains: to understand the world. To restrict quantum mechanics to be exclusively about piddling laboratory operations is to betray the great enterprise.”
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More recently…for example, fractals and deterministic chaos.
The fractal concept attempts to model a “new” class of mathematical objects, in a way made possible by computers. Yet even this idealization was soon outgrown and generalized with the idea of ‘multifractal’—with non-constant ‘fractal dimension’—in order to model yet deeper complexity. Nevertheless, the basic premise remains the same: to reduce complexity to an idealization, the found to the made.
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…other sense modalities, which are excluded on the grounds that they lack precision or introduce irrelevant content into knowledge.
For example, the subjective perception of temperature by skin was replaced by visual reading of a thermometer scale; the kinesthetic sense of weight or force was replaced by visually reading a scale attached to a spring. This allowed quantification and also overcame the problem, recognized by the Greeks, that the perception of temperature or weight depended on the state of tissues.
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The reality of the material world was supposed to be independent of the embodied human observer, a condition that seemed to be best satisfied by the visual sense.
Perhaps we also identify with the visual sense because it seems sheltered from the frailties and dangers to which the physical body is otherwise vulnerable. The evolutionary advantage of distance senses is advance warning. The psychological advantage, for a creature aware of its vulnerability, is precisely that the visual realm is detached from the somatic realm, free from its pains and injuries (unless, of course, an injury to the eyes. Yet, there are no pain receptors in the human retina, even though the retina is an evolutionary development of the skin). Creatures with an acute visual sense are often predators, so that vision is associated with the superior position of the predator. In the case of arboreal primates—and of the erect human—it is associated literally with a position “above it all.” Advance warning of any sort, however, is information that is only meaningful in terms of the organism’s physical welfare—which means the preservation of the soma and the genome. The eyes serve the body from which they are seemingly detached.
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Yet one should not confuse conceptual space… with real physical space…
Nor should one confuse perceptual space with external physical space. Perceptual space and temporal order must be acknowledged as mental constructions emerging from sensory input (which, albeit circularly, must have its own real basis). It would be wrong, however, to imagine that physical space (or time) “emerges” in some parallel way from the deeper level of some mathematical construction, on the analogy of the emergence of perceptual space from sensory input. For, the brain constructs perceptual space, while nothing (unless some god or superior alien) is constructing physical space. The ideas of shape dynamics and quantum graphity propose to explain how space “emerges” from a more fundamental domain, reducing extension itself to mathematical arrangements in an abstract network. Shape dynamics makes time universal and size relative, in contrast to general relativity, in which size is universal and time relative. However, the motivation behind the relativity of time was epistemic rather than ontological.
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However, nature may not be hierarchical in that way, but involve processes that are circular and mutually reducible.
The reductionism of Steven Weinberg, for example, is hierarchical. For him, various “arrows of explanation” converge on a final theory: “Our scientific discoveries are not independent isolated facts; one scientific generalization finds its explanation in another, which is itself explained by yet another. By tracing these arrows of explanation back toward their source we have discovered a striking convergent pattern—perhaps the deepest thing we have yet learned about the universe.” [Weinberg DFT p19] Thus, according to him, problems in high-temperature superconductivity will be solved in terms of elementary particle physics (because it is more fundamental) whereas problems in particle physics will depend crucially on further high-energy experiments, and will not draw on research in superconductivity. Robert McLaughlin, for one, does not share this bias.
Weinberg writes: “Think of the space of scientific principles as being filled with arrows, pointing toward each principle and away from the others by which it is explained.” [p6]. But what are the “dimensions” of this “space”? Surely it must include the theorist-observer, if only because it is a space of “principles,” not things or even laws. Weinberg takes vectors as a metaphor, perhaps referring also to the convergence of universal expansion backward in time. However, these are arrows of implication, while the space in which they “converge” is not defined. The metaphor is little more than a circumlocution to justify his belief that a final theory is inevitable. Such arrows may not in fact converge but be circular.
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Action-at-a-distance is an example of concepts that are embraced because they work mathematically more than because they make intuitive sense. In spite of Newton’s own reticence and Leibniz’ opposition, the notion of action-at-a-distance became a hallmark of the classical program, to assimilate mechanical phenomena to forces acting instantaneously across empty space between localized objects. Ironically, this had been viewed as unscientific by many thinkers of the early 18th century, who could only imagine such instantaneous action as an unphysical expression of divine will. [Max Jammer Concepts of Force Harvard UP 1957, p148] Action-at-a-distance is an example of concepts that are embraced because they work mathematically to serve prediction, more than because they make intuitive sense. A basic problem is the instantaneous transmission of force, defying Special Relativity. Fields had been introduced to mediate the transmission of forces and fill the embarrassing void between objects—which, however, were still conceived as the source of the forces. But mixing these metaphors had its own problems: particles creating fields, which react in turn on the particles, producing mathematical divergences that could be avoided by considering particles alone, interacting across empty space. [John Earman A Primer on Determinism D. Reidel Publishing Co., 1986, p53] Classical physics, no less than quantum physics, is plagued with inconsistencies and violations of common sense. Hence, Euler’s early (c.1736) attempt to resolve logical problems concerning causality and force by axiomatizing physics. This was supposed to trump the inherent problems by an act of fiat, rendering physics consistent and logically necessary rather than contingent. [Max Jammer Concepts of Force Harvard UP 1957, p211-12]
Once could say that, from the beginning, science attempted to replace animistic or teleological accounts of cause and effect with descriptions of motion or change of state. This shift in explanatory terms from intention to extension corresponds to a shift from 1st-person to 3rd-person description, according to the preeminence of the visual sense. The concept of force (and of efficient causal more broadly) may be a hold-over from a more body-oriented notion of agency. Like causality, the very concept of force had been troublesome from the beginning, and continued to be debated throughout the 18th and 19th centuries. Some criticized it on metaphysical grounds, as implying a kind of non-material agency. Others took a psychological approach, to reveal the origin of the concept in muscular exertion and will, projected onto inanimate objects. Conceiving force in terms of motion was part of the program to reduce all physical variables to extension. In extensional terms, force can be defined by the deviation of an object from its inertial course; but then its inertial course is circularly defined as the path the object follows in the absence of forces! Concepts of force and mass were mutually and circularly defined, as in Newton’s force law, f=ma.
Space and time, of course, have proven to be far from straightforward concepts. Empty space is something of a paradox, after all, for it suggests the notion of container. The container may be empty of content, but still implies some limiting boundary that could itself be contained in a larger volume, nested like Russian dolls. Is the container material? If so, what of the space contained? Is space the volume taken up by objects or their location in some larger volume? Is space the distance between objects or a reference frame in which to locate them? Is it a physical medium that can influence its contents, or be influenced by them?
It defies imagination to try to conceive either an infinite universe or a finite boundary to the universe. (It was not only empirical evidence that led Copernicus to reject Aristotelian cosmology, but also its internal contradictions. For instance, the outermost of the celestial spheres had to rotate in order to explain the daily motion of the stars; yet, it also had to be immobile, since movement would imply a larger space beyond it in which it rotated, in which case it is not the outermost sphere!) [Max Jammer Concepts of Space Harvard UP, 1969, p73] At the other end of the scale, a particle of finite mass and energy can neither be concentrated in a dimensionless point, nor be extended indefinitely through space, without violating reason. If space is to be judged empty (Euclidean or flat) by its inertial effects, then any test particle introduced to determine the presence or absence of such effects obviously renders it no longer empty; and any material reference frame serving to measure such effects would introduce them. (Bridgman criticized the notion of empty space as unverifiable because any test of emptiness would contradict itself by containing a test particle. The notion of field, or a metric of space, also implies a test particle that could subtly change that metric.) Similarly, if time is to be judged by cyclical processes (such as vibrating atoms), one wonders at the meaning of time in the absence of such processes—for example, before the universe cooled enough to permit the existence of atoms and other timekeepers.
Relative positions or relative speeds do not require an absolute reference frame. Accelerations, however, induce inertial forces that can serve as an absolute frame. The meaning and source of these forces remain controversial. While Descartes, Leibniz, and Berkeley held that all motion was relative, Newton sought to establish the true motions of things in relation to an absolute framework: space itself. He pointed to centrifugal force as evidence of an absolute space, but Mach later proposed that it could be explained relationally, as an effect induced by rotation relative to a much larger gravitating mass—perhaps the universe as a whole. Some medium would be required to transmit this influence at a finite speed. While the aether had served as a physical basis for an absolute reference frame, as well as a medium for transmission of electromagnetism, this proved untenable by the failure of Michelson-Morley type experiments to detect motion relative to it. Though Mach, like Berkeley and Leibniz and some medieval thinkers, had argued logically that rotation is only meaningful in relation to some actual reference frame, some modern cosmologists entertain the concept of the whole universe itself in rotation. (For example Shi Chun, Su and M.-C., Chu “Is the universe rotating?” arXiv:0902.4575v3 June 2009.) This paper examines possible effects of galaxy rotation, and proposes an alternative explanation in terms of a global rotation that could induce a total net spin of galaxies. Further, that global rotation might explain the accelerating expansion of the universe. Without assuming some kind of larger space within which the visible universe is situated, it remains unclear how these forces could be generated, or with respect to what it would be rotating. On the other hand, a preferred direction of rotation of galaxies might be evidence of such a larger space. (See also: “Was the universe born spinning?” physicsworld.com July 25, 2011.) All in all, the nature of fields and of space as real entities remains unclear.
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The idealist thread…in collecting, selecting, and interpreting data.
In many instances, theory confidently overrides apparent fact or reasonable doubt. A famous example is Einstein’s conviction that a failed experimental confirmation of General Relativity (Eddington’s 1919 expedition) would have meant so much the worse for the experiment. A similar situation had confronted the Copernican theory, which was enthusiastically embraced because of its theoretical appeal, despite the fact that some people doubted it even at the close of the 17th century, largely because of the unsettled question of stellar parallax. (A moving earth should produce an apparent motion of some stars against a background of others. This is in fact the case, but could not be detected at the time.) On the other hand, Kepler, sought to explain the dimensions of the solar system in terms of a purely theoretical “harmony of the spheres.” This Platonic scheme consisted of nested geometrical solids, through which he hoped to show the necessary values of certain numbers, such as why there were precisely six planets and their relative distances. He eventually realized that a scheme of geometrical solids could not work out even in theory, for the same reason that an “even tempered” musical scale cannot be mathematically precise (the real intervals involved cannot all be expressed as exact ratios). Yet he never gave up hope for his pet idea. Today, astronomers consider the radii of the planetary orbits to have been a matter of chance, or initial conditions, and not derivable from fundamental theory.
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In short, realism and idealism are complementary aspects of knowledge…
At the end of the 19th century, for example, classical physics had come up against the contextual limits of its realism, in the domains of the very fast and the very small, both of which involved the wave-particle duality of light. In one domain, the presumed medium for a wave explanation of optical phenomena led to logical and factual contradictions. No motion of the observer with respect to a supposed medium could be detected; the speed of light appeared to be a constant with respect to an observer in any state of (uniform) motion. This anomaly did not accord any better with the particle interpretation of light, which implied the Galilean addition of velocities, hence a variable measured speed of light. The second domain also involved light, in failing to explain the distribution of radiated frequencies in terms of classical continuities. This led to Planck’s law, the quantum, an inherently statistical approach to nature, and limits to the meaning of individually knowable micro objects. Any way you sliced it, light did not appear to behave according to realist expectations. In neither domain did physics easily let go its realist expectations. While the ether was abandoned, the field concept was retained, except that now it could not be identified with an absolute frame of reference. To postulate the invariant speed of light in “empty” space was a boldly idealist move. Ingrained realism, however, would then lead to corollaries of “time dilation” and Lorentz “contraction,” with the belief that time is a substantial flow that “really does” slow down at high velocities and objects “really” do shrink. In other words, in was difficult to fully maintain a purely relational perspective. The same held true in the quantum realm, when it was supposed that individual entities must “really” have positions and velocities, even when these could not be actually measured.