Here, for the time being we come to a stopping point. The project is not complete and many interesting and important problems are still unsolved or only partly solved, but the task is of such a nature that it will never be complete; no matter how far we go there will always be unexplored territory ahead. The subject matter that has been covered herein should, however, be more than adequate to demonstrate that the theoretical universe that necessarily exists if the Fundamental Postulates are valid is identical with the physical universe in which we live and upon which we make our observations. No work of finite proportions could penetrate very far into the profusion of details and minor variations that characterizes almost every physical phenomenon, but we have explored the major relationships all the way from the force characteristics of the smallest atom to the ultimate fate of the largest galaxy.
At no point in this wide field of coverage have the Fundamental Postulates failed to give a straightforward answer. It has not been necessary to treat anything other than space-time itself as an unanalyzable quantity; no limitations on the scope of applicability of the basic laws and principles derived from the Postulates have been required; no mysterious forces or special behavior characteristic have had to be postulated to account for discrepancies. Perhaps some of the answers are incomplete or only partially valid, but if and where this is true the fault undoubtedly lies in imperfect interpretation, as the validity of the basic principles is supported by an overwhelming mass of evidence.
As indicated in the introductory paragraphs, the general policy upon which the original program for this investigation was based called for retracing those steps taken in recent years which have had the effect of divorcing physical theory from physical reality, and making a new start along a route more closely defined by established physical facts. The somewhat unexpected, but in retrospect quite logical, result of following this policy has been in essence a return to the mechanical model. There are some features of the new theoretical structure which may give rise to conceptual difficulties, at least on first acquaintance, but this theory reduces all physical phenomena to motion, and in general it should meet the specifications of those who agree with Kelvin in wanting an explanation of the physical universe which can be visualized: a demand that modern scientific opinion has been inclined to look upon as naive and even somewhat juvenile.
It will also be noted that the mathematical development of the basic relations is extremely simple. This is another result that was not anticipated. In fact, a considerable amount of time was wasted in the early stages of the investigation in attempting to overcome obstacles by direct mathematical assault. Invariably such attempts were totally unsuccessful and when the true relationships were finally discovered, usually in a roundabout manner through the medium of advances made in some related fields, it was always found that nothing more than a very simple mathematical treatment was required. After this same succession of events had been repeated several times it finally became clear that the uniformly negative results were not accidental; that they involved an important fundamental principle. The physical relations being studied were basic and therefore simple. In a universe wherein the complex is built up from the simple, no complex physical mechanism can exist until the simple basic elements have been developed to the point where complex relationships have emerged. The mathematical expressions of these basic relations must then be equally simple, as the true mathematical representation of a physical phenomenon cannot be more complex than the phenomenon itself. The eventual recognition of this principle contributed immeasurably to the solution of problems subsequently encountered, as any hypothesis which could not be represented in simple mathematical form was immediately characterized as unacceptable, forcing the channeling of the available time and effort into a search for the unrecognized true relationship rather than dissipating it in fruitless mathematical investigation of hypotheses based upon accepted ideas which are now seen to lack validity.
As a final word, it may be appropriate to say something about the general nature of the results. There are, no doubt, those who will feel that the development of new information indicating that many of tile accepted scientific theories are erroneous shatters their belief in the permanence of scientific truth in general. Obviously if we are to discard today what we accepted as established facts yesterday, science will have lost its unique standing as a permanent and ever-growing systematic arrangement of knowledge. But this is not the true situation; the new information brought out in this work has not in any way disturbed the standing of any established facts or principles of science; it has merely demonstrated that some of the interpretations of and inferences based upon these established facts are in error.
It is true that there has been an unfortunate tendency in recent years to confuse fact and speculation and to elevate mere theories (relativity, for example) to a standing coordinate with or even superior to established facts. All too often we find statements of pure theory introduced by “It is now known that…”, “It is certain that…”, “Modern science has proved that…”, etc., when the introduction should be “We think…,” or some equivalent. One of the major tasks involved in carrying out this present program of investigation has been to separate fact from assumption and inference. But this is no reflection on science; it merely means that some scientists, by no means all, have succumbed to a characteristically human but definitely unscientific tendency to accept presumably authoritative pronouncements without adequate analysis and critical appraisal. One of the particularly subtle arguments that has helped to confuse the issues and to blur the line between factual an non-factual material is the contention so often raised that the theory under consideration is able “in principle” to explain all details and to reproduce all experimental values, and that inability to achieve this result in actual practice is merely due to mathematical complexity beyond the capabilities of existing facilities. In reality, of course, this “in principle” argument is a means of evading the issue, not of meeting it. Unless and until a hypothesis can be tested against facts it remains a hypothesis, no matter what it can do in principle.
Whatever advances have been made in the present work have not been the result of using any different methods but have been achieved by a more rigorous application of the recognized scientific disciplines: a more critical examination of the validity of the inferences drawn from experimental results, a more careful separation of facts from assumptions, and a more ruthless policy of discarding theories which cannot show full quantitative agreement with observation. Scientific methods of investigation and critical evaluation based upon established facts as the ultimate authority are the most powerful tools ever devised by man for the advancement of knowledge, and our rate of progress toward a better understanding of the world in which we live will be largely dependent on the extent to which we take advantage of these available tools.