Limits of Science?. John E. Beerbower
to this ultimate question, it is important to recognize the fundamental limits of our current understanding and knowledge of the world around us. It is not just the matter of what new discoveries are to be made at the fringes of our existing knowledge, but of how much of what we think we already know will turn out to be wrong. Thus, it is essential—and scientific—to remain constantly open-minded and skeptical.
Some leading scientists and historians of science have made this point quite forcefully. The renowned twentieth century theoretical physicist Richard Feynman “recognized—as scientist and as philosopher—that the chain of explanation never ends; it never really reaches an anchor. ...Physicists had hands-on experience with uncertainty, and they learned how to manage it. And to treasure it—for the alternative to doubt is authority, against which science had fought for centuries. ‘Great value of a satisfactory philosophy of ignorance,’ Feynman jotted on a sheet of notepaper one day, ‘teach how doubt is not to be feared but welcomed.’” James Gleick, in the Introduction to Richard Feynman, The Character of Physical Law (1994) (originally published by The British Broadcasting Corporation in 1965), pp.viii, x. Daniel B. Botkin, in a recent Op-ed column in the Wall Street Journal, also invokes Feynman in cautioning about absolutism in scientific debates: “How about a little agnosticism in our scientific assertions—and even, as with Richard Feynman, a little sense of humor so that we can laugh at our errors and move on? We should all remember that Feynman also said, ‘If you think that science is certain—well that’s just an error on your part.’” “Absolute Certainty is Not Scientific,” Opinion, The Wall Street Journal, December 2, 2011.
In the words of Joseph Bronowski: “Science is a very human form of knowledge. We are always at the brink of the known, we always feel forward for what is to be hoped. Every judgment in science stands on the edge of error, and is personal. Science is a tribute to what we can know even though we are fallible. [But, nonetheless, scientists need always to heed the words of] Oliver Cromwell: ‘I beseech you …think it possible you may be mistaken.’” The Ascent of Man (1973), p.374.
There has, in fact, even been some relatively recent academic interest expressed in the importance of ignorance. Columbia University professor of neuroscience Stuart Firestein describes a course that he began teaching in 2006 entitled Ignorance. Ignorance: How It Drives Science (2012). The New York Times reports that a professor of surgery at the University of Arizona, Marlys H. Witte, began teaching, despite some resistance, a class entitled “Introduction to Medical and Other Ignorance” in the mid-1980s. James Holmes, “The Case for Teaching Ignorance,” The New York Times, August 24, 2015. Holmes adds that “The study of ignorance…is in its infancy.” In his book, Firestein stresses how what we do not know frames the questions asked by science and that the evidence of good answers or discoveries is the new questions that those discoveries reveal. He even praises the process of writing grant applications because that process focuses on the unknown and how one might go about finding answers. Ignorance, p.59.
Of course, working scientists are focused on and engaged in, and sometimes obsessed by, their efforts to advance the particular fields that they have chosen. That focus is good. What they do is noble and represents some of the best of human activity and aspiration—the quest for knowledge and the need for understanding. The fact, as I attempt to demonstrate in the following chapters, that they fail to “know,” and seem doomed never really to “understand,” is irrelevant. The striving itself is worthy. See, e.g., Albert Camus, The Myth of Sisyphus and Other Essays (1991) (translation by Justin O’Brian), p.123: “The struggle itself toward the heights is enough to fill a man’s heart. One must imagine Sisyphus happy.”
With regard to the inspiration that can be generated by the efforts of those who strive to create something beyond themselves, Lord Rees has used the example of Ely Cathedral, arising out of the fens of East Anglia. He spoke in tribute to those who “built this cathedral—pushing the boundaries of what was possible. Those who conceived it knew that they wouldn’t live to see it finished. Their legacy still elevates our spirit, nearly a millennium later.” From Here to Eternity, p.150. The dignity and grandeur of the quest matter.
In the opening chapters, I shall discuss the philosophy of science, focusing on theories of knowledge and proof, and then the nature and role of mathematics. Next, I review some methodological debates that arose among economists during the twentieth century, which I find to be suggestive of the nature of these problems in the social sciences and to be a potentially more accessible context in which to present the philosophical and methodological issues. Awareness of the philosophical underpinnings of the methods and methodologies employed by natural scientists and social scientists provides, I believe, significant insights into the discussions of the state of scientific knowledge in the various fields addressed below. (As stated by the nineteenth century economist John Neville Keynes [the father of the better known twentieth century economist John Maynard Keynes]: “In the long run, time cannot but be saved by making a preliminary study of the instruments of investigation to be used, the proper way of using them, and the kinds of things that they are capable of yielding. For in so far as methods of reasoning are employed without due regard to the conditions of their validity, the results gained must likewise be of uncertain validity….” The Scope and Method of Political Economy (1891), p.4.)
With this background, I go on to look at major issues in biology (as reflected in Darwinian theory), physics, particle physics and quantum mechanics, cosmology and neuroscience, trying to span the traditional sciences as well as the newer areas of scientific investigation. We shall see that most areas of science began as what we would generally call philosophy, then with the introduction of empirical analysis and the extensive use of mathematics became more and more like the modern concept of science. That trend continues, leading in the last century to the enthusiastic speculation that someday, even someday soon, “science” might encompass everything and explain it all and, more recently, to this century’s apparently increasing minority concern that perhaps science will not do so in the end, because science (as we know it) cannot do so.
But, in all events, science is a continuing source of wonder. We will continue to be awed by the creativity, the beauty and the elegance of the theoretical edifices that man has been able to erect to date in his search to understand the world in which we live. And, we should also marvel at and be inspired by how much we simply still do not understand.
The Goal of Comprehension
Initially, in thinking about how we know things, it is probably common to seize upon the distinction between direct sensory perceptions and knowledge from inference or deduction. We feel a solid surface; we see a star; we hear the waves; we taste and smell the ripe fruit. However, as a result of the discoveries of science, we can all appreciate how tenuous that distinction really is. Surfaces are not solid, but composed of molecules the volume of which is only a small part particles, part energy and a lot of nothing (even though, from most viewpoints relevant to normal existence and daily functioning, surfaces are still solid); some of the stars we see are no longer there and have not existed for thousands or even millions of years; sound consists of vibrations or waves transmitted through the air that have significance because of their impact on our eardrums; we can smell because our receptors react to molecules floating through the air. And sight? Photons activate the receptors that feed the optical nerve.
Then, of course, to be complete, one still needs to examine the next level: how the physical stimuli of our nerves and receptors are transmitted to and, more importantly, “interpreted” by our brain. Indeed, as we shall discuss in a later chapter, it is the brain, not the sensory organs, that perceives the physical world. Moreover, the functioning of the brain is frighteningly complex and, it seems, in some ways counter-intuitive.
It is a different aspect of mental activity that I want to discuss now, however. It seems accepted wisdom that we interpret or understand things about ourselves only through the use of models and theories. In other words, sensory perceptions or other “information,” apart from that which generates an instinctive response, can be processed only through theories we hold about how the world around us functions. We are not objective, neutral observers; instead, we absorb information through the organizing filters of preconceptions about causality and other relationships.