Elementarity and Reality in Particle Physics

  • William A. Wallace
Part of the Boston Studies in the Philosophy of Science book series (BSPS, volume 3)


Recent developments in high-energy physics have not been encouraging for anyone interested in the problem of elementarity. Not only has the number of so-called elementary particles increased rapidly during the past few years — from less than a half dozen to thirty, then to over a hundred — but also the propriety of referring to these as ‘elementary’ has been increasingly questioned.1 Part of the latter concern arises from the great number of particles, for it would seem that the elements of which things are constituted should be few in number. A more puzzling paradox arises from the fact that many of the particles being discussed by physicists, particularly those referred to as strongly interacting particles, seem in some sense to be composites of one another.2


Type Species Junior Synonym Original Designation Peripheral Skeleton Choanocyte Chamber 
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  1. 1.
    See Chen Ning Yang, Elementary Particles: A Short History of Some Discoveries in Atomic Physics, Princeton 1962; also G. F. Chew, M. G.ll-Mann, and A. H. Rosenfeld, ‘Strongly Interacting Particles’, Scientific American 210 (1964) 74–93.Google Scholar
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    An introductory study is that of R. B. Braithwaite, Scientific Explanation, New York 1953. (Reprint, 1959.)Google Scholar
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    Aristotle presented two analyses whereby a person may come to a knowledge of primary matter, one pertaining to metaphysics and the other to natural philosophy. For a modern explanation of the first type of analysis, see Ernan McMullin, ‘Matter as a Principle’, in The Concept of Matter (ed. E. McMullin), Notre Dame 1963, pp. 169–208; for a similar account of the second type, see V. E. Smith, The General Science of Nature, Milwaukee 1958, pp. 52–122.Google Scholar
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    This was common teaching in the Middle Ages, although there were two variations on the teaching, one stemming from Avicenna and the other from Averroes. According to Avicenna, the elements remain in the compound actually as to their substantial forms while their qualities are present only in a remiss state; in his view, elemental qualities are capable of intension and remission and have a certain latitude according to which they can be found with a particular substantial form. According to Averroes, on the other hand, both the substantial forms of the elements and their qualities undergo a remission and remain within the compound in a remiss state, the substantial forms of the elements having a peculiar existence in the compound midway between that of substance and accident. For details, see A. Maier, An der Grenze von Scholastik und Naturwissenschaft, 2d ed., Rome 1952, p. 29. Theodoric followed Averroes, as did most of his contemporaries.Google Scholar
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    The statement is often made by physicists that, although particular theories of the atom or of elementary particles may pass out of vogue, energy levels are here to stay. The analysis of experimentally verifiable data such as measurements of energy levels forms the basis for the assignation of quantum numbers, and thus these too would seem to be ‘here to stay’.Google Scholar
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    A diagonal transition is permitted in Gell-Mann’s system, it would seem, because the mass number is conserved while both Q and I (or Y) are changing. In Theodoric’s system, where only two parameters are variable (H and W) and there is no constant such as mass number to be conserved, diagonal transitions are automatically disallowed.Google Scholar
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    Equivalently, this grants to both an entity and its attributes an ontological status while maintaining that the entity is more fundamental than its attributes; in scholastic terminology, both substance and accident are real, but substance is more fundamental than accident and as a consequence can enter into the definition (or explanation) of accident.Google Scholar
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    According to this terminology, the real is divided into the potential and the actual. For example, rationality in a human being is real: it is potential in the child who cannot yet actually reason, although he has the basic capability or potency to do so; it is actual in the adult who does in fact reason.Google Scholar
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    The term ‘elements’, it may be noted, is essentially relative or relational in meaning. For example, syllables may be referred to as the ‘elements’ out of which words are composed of letters as further ‘elements’. In like manner, what is regarded by the chemist as an element in his science need not be so regarded by the physicist in his; or, what is regarded by the physicist as an element in one application need not be so regarded in another application.Google Scholar
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    The sense in which an elementary particle may be regarded as a ‘construct’ is thus twofold: it may be ‘constructed’ or contrived experimentally, by laboratory conditions, or it may be ‘constructed’ or contrived logically, by the theoretician in an attempt to explain high-energy experiments. Recent philosophers of science seem to neglect the first sense entirely and to overemphasize the second sense.Google Scholar
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    What is involved here is not time duration alone, but a stable nature that seeks continued self-preservation against the ravages of extrinsic deteriorating agents.Google Scholar
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    See D. Böhm, Causality and Chance in Modern Physics New York 1957. (Reprint 1961.)Google Scholar
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    For an exposition and defense of this view, see N. R. Hanson, ‘The Copenhagen Interpretation of Quantum Theory’, Philosophy of Science, (ed. A. Danto and S. Morgenbesser ), New York 1960, pp. 450 - 470.Google Scholar
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    See S. Vonsovski and G. Kursanov, ‘Lois dynamiques et statistiques dans les phé-nomènes atomiques’, Physique: Recherches internationales à la lumière du marxisme 4 (1957) 177–178; also M. E. Omelianovski, ‘Das Problem der Realität in der modernen Physik’, in Atti del XII Congresso Internazionale di Filosofia, Florence 1960, Vol. II, p. 335. Cited by F. Selvaggi, Causalità e Indeterminismo, Rome 1964, p. 373, fn. 26–27.Google Scholar

Copyright information

© D. Reidel Publishing Company / Dordrecht-Holland 1967

Authors and Affiliations

  • William A. Wallace
    • 1
    • 2
  1. 1.Catholic University of AmericaUSA
  2. 2.St. Stephen’s PrioryUSA

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