This review appears in the Summer 2014 issue of Modern Age. To subscribe now, go here.
The Nature of Scientific Explanation by Jude P. Dougherty
(Washington, DC: Catholic University of America Press, 2013)
“It has been scientifically proven that . . . ” are words that strike fear into one’s opponents and quickly silence contrary opinions. Though often unjustified, they reflect the outsized prestige that science has in our society, and its great potential to steer our culture and civilization. So the question of what science is, what it can do, and what its limits are, should be a top priority for us, but it is not. So any serious work that looks at these and related issues is welcome, especially if it comes from a long-standing tradition with roots deep in Western civilization itself. This short book addresses the question of scientific explanation in the Aristotelian context. It consists of seven chapters (“Lectures”) and an epilogue. Despite its title, it is not a systematic discussion of scientific explanation, how science operates, or the philosophy of science. It is rather a collection of essays loosely centered on the theme of science and Aristotelian philosophy. It does not start with a discussion of how science operates in practice and then show that this is consistent with Aristotelian ideas; it proceeds rather the other way round, giving Aristotelian philosophy the high ground and then endeavoring to show that science can fit into that paradigm.
Jude Dougherty’s main point seems to be that science is a realism-based enterprise and thus it falls under Aristotelian philosophy. He gives ample evidence for the former, and at least some of the ways that scientists think about reality fit with notions such as causality, essence, and substance. Of course, to take a realist view of science (i.e., belief that scientists are actually finding out about real things) is not the same as to adopt Aristotelian philosophy wholesale. Aristotelian metaphysics and epistemology offer one possible way to approach science as realism, though not the only way; the author, however, does not consider this question. The fact is that science allows us to penetrate more deeply into reality in the sense that it extends and systematizes our ordinary experience of the world. This penetration is not the same as knowing reality; for that, human understanding comes into play. Aristotelian philosophy is one way to seek this understanding, and the author rightly makes the point that science, by itself, is not the intuitive knowledge that we crave. Aristotle’s Metaphysics begins with the famous observation, “All men by nature desire to know,” and what they desire to know is reality.
But therein lies the problem: how do we incorporate something as vast as modern science into our knowing about reality? The fundamental flaw in the Greek view of knowledge is the assumption that one can understand the world by simply thinking about it; that is, through reflection on normal experience. The Greeks had no technology to view anything outside the normal realm of human experience—the very large, the very small, the very fast, the very high energy, etc. As a result, their views were shaped by such experience, and on that basis they extrapolated to all of reality. This does not work for science; experimentation is necessary. Though Aristotle is justly famous for his dissection work on plants and animals and his classifications, he did not formulate hypotheses and then test them empirically. His theory that plants get their food (and thus their mass) from the soil sounded reasonable, but clearly the relevant experiment was never done. As the author points out, it was not until the Middle Ages in Europe that the idea that one had to get his hands dirty in order to do real investigation of nature came of age with Grosseteste and others. But this did not come through the Aristotelians, who never really left the Greek tradition, but through the Benedictines and later the Franciscans. It can be argued that modern science grew out of the Franciscan tradition more than any other, and specifically the work of Scotus and Ockham (Grosseteste was associated with the Franciscan order but not a member).
The author correctly observes that there are aspects of reality that elude the senses but that are nonetheless conveyed to us by our perceptual system. This permits us to inquire about reality utilizing the concepts of ordinary experience as well as those of science. As Abbott Suger famously said in the twelfth century, “De materialibus ad immaterialia” (De Administratione 33). He was referring of course to the soaring new Gothic church of St. Denis that he was building, but his remarks hold generally. Kant’s critical philosophy, perhaps the only serious rival to realism in the minds of some scientists, crashed and burned in the nineteenth century with the development of non-Euclidean geometries and their later incorporation into the non-Newtonian physics of relativity in the early twentieth century.
Dougherty’s project would be quite useful if the discussion addressed the really difficult problems posed by science for any Aristotelian philosophy. These problems include the failure of the change paradigm in Aristotle—substantial change does not involve going down to prime matter and renewing with a different form; the inadequacy of Aristotle’s place theory of motion; nonlocality in quantum systems (visible on a macroscopic scale); and the probabilistic nature of reality, which is fundamental and not an artifact of our descriptions, to mention only a few. Instead the book seems to be a critique of theories and ideas that few if any practicing scientists now hold or ever held, although some philosophers have advocated them from time to time. Most (in fact virtually all) scientists are realists and believe that what they are investigating is real, even if it may behave in ways radically different than objects in our day-to-day life. At the subatomic level, for example, particles such as quarks cannot be visualized, and interactions between particles must be understood with the complicated and probabilistic mathematical descriptions of quantum field theory.
Mathematics indeed is a language for talking about nature that extends our ordinary language and thus allows us to understand these realms of reality to the degree that we can do so; it is not a vacuous metaphor. The author claims that “when physicists form a pure abstract mathematical equivalent of a given atomic structure, a structure that is often unimaginable because it is devoid of ontological content . . . the inferred structure has the character of a fiction, a mere symbol, for the real nature [is] unknown in itself” (15). This is radically false: the structure is “unimaginable” because it is foreign to our ordinary experience, not because it is ontologically deficient in itself. With time many of the structures hypothesized by science have been actually seen, and even those that cannot be seen because they are too small or too distant become familiar through measurement, and thus their ontological content becomes manifest. Dark matter, for example, is almost certainly real, but we can never see it; nonetheless, we can investigate it and try to determine its characteristics.
Similar strictures apply to the author’s claim that “physico-mathematical science is not formally physical science, although it is physical as regards the matter in which it verifies its judgments, and although it is oriented toward physical reality and physical causes as the terminus of its investigations. It does not, however, aim to grasp the inner ontological nature of its subject matter” (12). To anyone in the physical sciences, this is simply absurd. Physical science and scientists are in fact interested in the nature of their subject matter, in all respects; it’s just that that nature is accessible to us—insofar as it is accessible at all—only through the language of mathematical physics. Through that and experimentation, we have to develop whatever knowledge and intuition we can possess of the nature of the objects and processes we study. And indeed, we have developed an intuition of atoms that did not exist two hundred years ago, and perhaps two hundred years from now our intuition of forces of nature and their unification will be better. But this will not come from contemplation but further research and study by scientists. As already noted, what science cannot do by itself is to formulate a comprehensive picture of reality; its role there is restricted to providing us with the basic material needed to form an intuitive understanding of reality. It does not appear that we shall ever attain anything like a “grasp of the inner ontological nature” of most of the objects we study, nor is that really necessary.
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Dougherty’s discussion of mathematics seems rather superficial, and I can only conclude that his acquaintance with the subject—especially modern mathematics—is marginal at best. He attempts to place Euclidean geometry—supposedly more intuitable—front-and-center for philosophy, as is typical for Aristotelian thinkers, with the justification that it is how we intuit the world. But this won’t do; mathematics has long since moved beyond Euclidean geometry, however important it was for creating the enterprise of mathematics as we know it. And even with respect to Euclidean space, anything beyond three dimensions ceases to be intuitable, though it can be handled quite well with the tools of mathematics.
This is not just an academic exercise—large parts of the modern world function on the basis of higher-dimensional Euclidean spaces. For example, all types of regression analysis utilize higher-dimensional Euclidean space. The key is to have a structure for the space and a metric. Everyone is familiar with the Euclidean metric in two dimensions, which measures distance. But metrics exist in other spaces, spaces that may be composed of functions, for example, and that may be infinite in dimension. These spaces are no more or less real than Euclidean space, and often serve well to characterize aspects of the world. So when the author says, “Whereas Euclidean space is directly grasped by intuition, others of necessity are referable to the Euclidean notion of space for their intelligibility,” this is wide of the mark. These spaces share some notions with Euclidean geometry, but their “intelligibility” is strictly a function of their mathematical structure. Very little of modern mathematics can be immediately grasped, but with time and a lot of concentrated thought, it can be understood. We intuitively understand Euclidean concepts because they happen to fit our day-to-day world well and we have used them since childhood; if we spent that much time in a non-Euclidean world, we would understand it quite well too.
The author believes it is necessary “to philosophically study the first principles of mathematical science, which alone can provide a rational account of the true nature of mathematical abstraction and the mental objects it considers” (12). But what does this mean? “Such a study would embrace the mutual relationships of the continuous and discontinuous, the real meaning of surds [irrational numbers] and transfinite numbers, the infinitesimal, non-Euclidean space, and the validity of mathematical transcripts of physical reality such as quantum mechanics and the theory of relativity” (12–13). This sentence does not explain anything: the mathematical definition of continuity clarifies what it is, and thus the discontinuous. Irrational numbers do not have any “real” meaning: they just are, and there are lots of them.
There are questions to investigate about transfinite numbers, such as the truth of the continuum hypothesis, but not their real meaning—they too just are. And quantum mechanics is not a “mathematical transcript” of reality but a theory about reality, which requires the language of mathematics to be understood. Nonetheless, this points in the right direction: we can ask meta-mathematical questions, and since Gödel, we know that the task of mathematicians is to investigate the properties of the real structures they create. The language of mathematics clarifies this: “Let A be a Hilbert space,” and then investigate it by proposing and proving theorems.
The issue of final causality is addressed in lecture 5, entitled “The Principle of Final Causality.” This chapter jumps around quite a bit, with other types of causality, especially efficient causality, discussed at length. Dougherty correctly points out that empiricist tradition, including science, has restricted itself to material and efficient causality (56), though some have argued that scientific laws themselves represent a type of formal causality. Be that as it may, the important question is the nature of causality and the extent to which science actually probes causal relations. Causality is an especially difficult problem for the Aristotelian tradition because of its commitment to a particular deterministic version.
Though Dougherty obliquely criticizes Averroës’s view of causality, he doesn’t address the relevant aspects of it that have been defended even in our own time by philosophers of science such as Stanley Jaki, namely determinism and contiguity, both of which are severely challenged by the indeterminism and nonlocality of quantum mechanics. Perhaps the question can be put this way: do we really have knowledge of something if we do not know how it acts causally on other things through its own essence? This question comes up partly in the context of final causality. Is final causality necessary to understand science? Or is it something with which science needs to be concerned? In fact, the real question isn’t whether final causality is needed for science (it isn’t), but whether scientific explanations are or can be sufficient to explain all of reality.
The question of final causality is not of great interest except in biological contexts, where it seems that organisms and their component systems have been designed to achieve some end. On the other hand, many of the mechanisms employed, such as those responsible for homeostasis, are relatively simple feedback control systems, which give the appearance of final causality but are really just efficient causality. So it is difficult to infer final causality on the basis of such mechanisms, even if they do function to enable life. But final causality has become prominent recently with the growing awareness of the anthropic principle, which states that the universe is fine-tuned for life and that were any laws or initial conditions even slightly different, life could not have arisen. Although not a scientific principle, it utilizes the findings of science and the extremely small probability that so many things could have happened by chance to infer the final causality. Curiously, however, the author does not discuss this subject in the book.
The epilogue of the book is quite interesting but only tangentially related to the subject matter of the other chapters. It deals with the problem of freedom, rights, and education and culture in language that will be familiar to readers of this journal.
Overall this book will be valuable for those who want to get some insight into the way that science is understood and fitted into an Aristotelian framework. Those who are seeking answers to the hard questions this poses will have to look elsewhere. ♦
Thomas B. Fowler is adjunct professor of engineering at George Mason University and a retired systems engineer. His doctorate is in systems and control theory from George Washington University.