Now that we have completed our survey of the conceptual problems of quantum physics, what are we to make of it all? One thing that should be clear is that there is considerable scope for us all to have opinions and there is a disappointing lack of practicable experimental tests to confirm or falsify our ideas. Because of this, I intend to drop the use of the conventional scientific ‘we’ in this chapter and to use the first person singular pronoun wherever I am stating an opinion rather than describing an objective fact or a widely accepted scientific idea. This is not to say that everything in the earlier chapters has been free of personal bias, but I have tried to maintain a greater basis of objectivity there than will be appropriate from now on. I first want to refer briefly to a way of thinking about philosophical problems known as ‘positivism’. Encapsulated in Wittgenstein's phrase ‘of what we cannot speak thereof should we be silent’, positivism asserts that questions that are incapable of verification are ‘non-questions’, which it is meaningless to try to answer. Thus the famous, if apocryphal, debate between mediaeval scholars about how many angels can dance on the point of a pin has no content because angels can never be observed or measured so no direct test of any conclusion we might reach about them is ever possible. Opinions about such unobservable phenomena are therefore a matter of choice rather than logical necessity.
Now that we have completed our survey of the conceptual problems of quantum physics, what are we to make of it all? One thing that should be clear is that there is considerable scope for us all to have opinions and there is a disappointing lack of practicable experimental tests to confirm or falsify our ideas. Because of this, I intend to drop the use of the conventional scientific ‘we’ in this chapter and to use the first person singular pronoun wherever I am stating an opinion rather than describing an objective fact or a widely accepted scientific idea. This is not to say that everything in the earlier chapters has been free of personal bias, but I have tried to maintain a greater basis of objectivity there than will be appropriate from now on. I first want to refer briefly to a way of thinking about philosophical problems known as ‘positivism’. Encapsulated in Wittgenstein's phrase ‘of what we cannot speak thereof should we be silent’, positivism asserts that questions that are incapable of verification are ‘non-questions’, which it is meaningless to try to answer. Thus the famous, if apocryphal, debate between mediaeval scholars about how many angels can dance on the point of a pin has no content because angels can never be observed or measured so no direct test of any conclusion we might reach about them is ever possible. Opinions about such unobservable phenomena are therefore a matter of choice rather than logical necessity.
Now that we have completed our survey of the conceptual problems of quantum physics, what are we to make of it all? One thing that should be clear is that there is considerable scope for us all to have opinions and there is a disappointing lack of practicable experimental tests to confirm or falsify our ideas. Because of this, I intend to drop the use of the conventional scientific ‘we’ in this chapter and to use the first person singular pronoun wherever I am stating an opinion rather than describing an objective fact or a widely accepted scientific idea. This is not to say that everything in the earlier chapters has been free of personal bias, but I have tried to maintain a greater basis of objectivity there than will be appropriate from now on. I first want to refer briefly to a way of thinking about philosophical problems known as ‘positivism’. Encapsulated in Wittgenstein's phrase ‘of what we cannot speak thereof should we be silent’, positivism asserts that questions that are incapable of verification are ‘non-questions’, which it is meaningless to try to answer. Thus the famous, if apocryphal, debate between mediaeval scholars about how many angels can dance on the point of a pin has no content because angels can never be observed or measured so no direct test of any conclusion we might reach about them is ever possible. Opinions about such unobservable phenomena are therefore a matter of choice rather than logical necessity.
Despite scholarly consensus on the empirical facts, ever since its inception in the 1920s there has been deep disagreement about how to interpret quantum theory. “To interpret a physical theory is to say what the world would be like, if the theory were true.” All scientific theories require interpretation, since strictly speaking what they describe are our experiences of the world rather than the world itself. Thus, whether we are trying to explain or merely describe the world, we are always engaged in inference. To make inferences we need a context for interpretation. For any given claim this context is provided locally by related theories, more broadly by disciplinary paradigms, and ultimately by worldview claims about the nature of reality. The challenge in interpreting scientific theories is to integrate them into this hierarchy of knowledge. Usually this is not too difficult. New theories often require adjustments to nearby theories, but in doing so we can rely on paradigms to make them cohere. More rarely paradigmatic assumptions are themselves challenged, but in that case scientists can fall back on their worldview to make sense of the needed changes. By implication, the most difficult interpretive problems arise when our worldview is called into question, which leaves us without any frame of reference on which to fall back. Quantum theory poses a worldview problem. Prior to the quantum revolution the classical worldview could not be tested scientifically and so it was essentially metaphysical. Even though it corresponded to our experience of material objects, we lacked proof that it adequately represented the deep structure of reality. By giving us access to that deep structure for the first time, quantum mechanics made it possible to do such a test, or “experimental metaphysics.” Unfortunately, the results seemed to contradict classical assumptions, at least on the sub-atomic level.
We have now concluded our summary of the findings of modern physics, and may turn to consider how these findings affect the practical problems of philosophy and of everyday life. But let us first recapitulate the conclusions we have reached in our scientific discussion. Recapitulation Because we are human beings and not mere animals, we try to discover as much as we can about the world in which our lives are cast. We have seen that there is only one method of gaining such knowledge—the method of science, which consists in a direct questioning of nature by observation and experiment. The first thing we learn from such questioning is that the world is rational; its happenings are not determined by caprice but by law. There exists what we have called a ‘pattern of events’, and the primary aim of physical science is the discovery of this pattern. This, as we have seen, will be capable of description only in mathematical terms. The new quantum theory explained in the preceding chapter has provided a mathematical description of the pattern of events which is believed to be complete and perfect. For it enables us—in principle at least—to predict every possible phenomenon of physics, and not one of its predictions has so far proved to be wrong. In a sense, then, we might say that theoretical physics has achieved the main purpose of its being, and that nothing remains but to work out the details.
ENERAL philosophy claims to be the critical subject which lays down for all of us what we may be allowed to think, and yet it has played no part whatever in the great revolutions of human thought of the present century-those connected with relativity and the quantum theory. It might have been expected that the scientists would have been constantly consulting the philosophers as to the legitimacy of their various speculations, but nothing of the kind has happened. Since no one can dispense with some sort of metaphysic, each scientist has made one for himself, and no doubt they contain many crudities, but it would seem that a deep interest in metaphysic is a disadvantage rather than an advantage to the physicist-at least I have the impression that those of my friends who are most inclined to speculate on the ultimate things appear to be the ones whose scientific work is most hampered by doing so. Now I propose to risk a similar indiscretion. I want to embody in it the practical philosophy of a physicist, and I do not mean it as an attack on the pure philosophers, who are very reasonable people, only chargeable with the minor offence of not having made me want to read their books! I had better begin by stating shortly the ideas I intend to discuss. There is a notable contrast between the way we think about things and the way we think we ought to think about them.
During the first half of the century, positivism had a firm hold on the great majority of physicists. It appeared, however, in recent years that this method of analysis has lost its early creativity. Professor Hooker is among the increasing number of philosophers of physics who are concerned about this situation. His determination to redirect philosophical study to significant human problems is most re freshing. Unfortunately, I am afraid that his technique does not measure up to the difficulty of this task. He polarizes the issue by formulating two comprehensive and mutually incompatible world views and then pro ceeds to destroy positivism and vindicate realism. Since he cannot discern any merit in positivism, it is hard to avoid the implication that Einstein, Bohr, and Heisenberg were utterly misguided when they used positivist arguments to challenge classical dogmas. Instead of analyzing his paper point by point, I prefer to discuss the problem from my point of view. Let me start by clarifying first how I intend to use the terms 'real' and 'reality'. Curiously, the commonsense usage serves as a good point of departure. We usually know what 'reality' means in contrast to 'dream', 'illusion', 'deception' or 'error'. We know how to compare a photograph or a map with reality. There are situations in physics which are quite similar. We distinguish a real object from a hologram, and we know how to tell a 'real' effect from an experimental error, at least in the long run.
Today, many concepts from the dictionaries of academic psychology have entered the language of everyday communication. Perhaps the most common are the concepts of «subjective» and «objective». In many textbooks of psychology, «objective» is understood as something that belongs to the object itself, something that does not depend on the subject. The objective is opposed to the subjective-personal. Experimental research in the field of quantum physics questioned the division of the world into an impartial «objective reality» and its «subjective» (not impartial, biased) reflection, which provoked a crisis in this field of knowledge and the methodology of science as a whole. The main methodological problems of psychology are the question of the place of the mental in nature; on the relationship of mental and material phenomena, on the possibilities of human cognition - questions that also arose in the depths of quantum physics and were predetermined by the internal logic of their development. An excursion into quantum physics was necessary, firstly, for a deep understanding that reality is given to us in our sensations, perceptions, ideas and mental constructs (this was evidenced by the so-called «double slit experiment» and its interpretations) and we cannot say anything about reality as it is «in itself»; secondly, the realization that the foundations on which our knowledge is built differ from those in quantum physics. Currently, there is a dichotomy between material (physical) and conceptual reality. Thus, the principle of locality, which professes ordinary consciousness and according to which specific objects occupy a specific place in time and space, contradicts the principle of non-locality, according to which isolated systems do not exist at all and every particle of the universe is in «instantaneous» communication with all other particles. The world is created from the same quantum substance and it is impossible to say that one is the cause of the other. (This statement implies, in particular, a rethinking of the «principle of determinism» which requires the establishment of unambiguous causal relationships). The reality in which we live is not quantum, our language and stereotypes of thinking do not correspond to the nature of the phenomena described by quantum physics. It is about the deep properties of matter. Personally, I got the impression that the deeper you plunge into the world of atomic and subatomic, the more the outlines of the specific, material world familiar to us become blurred and the thinner the line between the physical and conceptual world, between the material and the spiritual becomes. The purpose of this article is to define the concepts of "objective" and "subjective" based on the analysis of achievements in quantum physics in the context of psychology.