CONTENTS PAGE INTRODUCTION BY PROFESSOR D. NOËL PATON, M.D., LL.D., F.R.S. ON looking back over a forty years' association with physiology nothing is more striking than the influence which the application of physics has exercised upon the progress of the sciences. I well remember that, as long ago as 1878, my first teacher began his lectures on the Institutes of Medicine by defining physiology as the application of physics and chemistry to the study of the body in action. But at that time the possibility of applying these sciences was limited. In the first place, their development, and especially the development of physics, was not sufficiently advanced. The dissociation of atoms into ions was hardly recognised, the significance of Graham's colloids was not appreciated, and the phenomena of surface tension had hardly been applied to molecular physics. In the second place, physiologists were then generally men trained for medicine whose education in physics and chemistry had been extremely limited. Of course, there were notable exceptions-e.g. Helmholtz and du Bois Reymond. These older physiologists had to be content with recording phenomena rather than with explaining them, and they loved to chronicle their observations in high-sounding Greek names. Can one ever forget the sense of profound knowledge which one enjoyed as a junior student in mastering such terms as "delomorphous" and "adelomorphous " as descriptive of the cells of the stomach? The so-called chemical physiologists were perhaps the worst offenders. For, having isolated, or thought they had isolated, some constituent of the body of quite unknown chemical constitution, they promptly gave it a name with no connection with its chemical nature, and these names have generally continued in use, to the confusion of generations of students. In the present age of "hormones " and "vitamines" one wonders how far the tendency has been eradicated. It was the what happens?" which interested these older workers: "Why it happens?" was generally beyond them, and vague theories of some peculiar and special vital action took the place of actual demonstration. Undoubtedly the association of physiology with the more exact science of physics, based as it is so largely upon mathematics, has had an enormous effect in getting rid of this habit of vague theorising and has materially helped to clarify minds "debauched with the so-called science of biology as Tait, in the early eighties, was wont to describe our mental condition. It has also stimulated the critical faculty, which insists upon a clear proof and demonstration as a basis of conclusions. It is much to be regretted that even at the present time the importance of a mathematical training, so essential for the study of physics, is not generally recognised, and that it is still possible to take a higher degree in science without this necessary preparation. It has been through the co-operation of physics and chemistry that the solution of many of the problems of life have been reached, and as the possibility of reaching these solutions has become more generally recognised, the spirit of scientific curiosity -the desire to know, which is the basis of all scientific workhas been stimulated; although probably in the future as in the past, humanity will still be divided into the enormously large class of those who have no real desire to understand the workings of nature and the very small class of those who have the spirit of curiosity, who do desire to know. These alone are the scientists, although many science graduates belong to the major class. With or without any wider diffusion of the spirit of curiosity, the development of the critical faculty and the better training of the younger workers in physics and chemistry has brought physiology nearer to the position of an exact science, and with this, its value as a training for students of medicine has greatly increased. The doctor, in making a diagnosis, has not merely to observe and record what has happened, but he must ascertain why it has happened. His problems are the same in nature and his methods are the same as those of the physiologist, and thus physiology has regained its position as the Institutes of Medicine. The doctor of the past considered that he had made a diagnosis when he was able to give his patient's disease a name. The physician of the future will care less and less for such names. He will simply be concerned with the solution of the questions "What is abnormal?" "Why is it abnormal?" Perhaps it is wiser not to enquire too curiously into the position of the physician of the present. The development of physiology on the lines indicated has also made possible the growth of the sciences of experimental pathology, of experimental medicine and of pharmacology; and the knowledge of disease and of its treatment has thus been put upon a sounder basis. All this has followed the adoption of physics and chemistry as the guides of the physiologists. In the present volume, Dr. Burns attempts to show the part which physics has come to play in the solution of the problems of physiology. A science of bio-physics has evolved in the same way as that of bio-chemistry. Perhaps some attempt should have been made in the title to indicate that it is the problems of the physiology of vertebrates rather than the basic problems of life generally which are dealt with. The book is intended for students of human physiology, although it cannot fail to interest all workers in biology. It demonstrates what a very large number of the characteristic reactions of living matter may be explained in terms of ordinary physical processes, and it thus shows the reduction which is taking place in the number of phenomena which some are still content to explain as due to a mysterious vital action instead of simply confessing that they are yet not understood. As the application of physics and chemistry to physiology is extended, it is safe to predict that fewer and fewer of these vital manifestations will remain unexplained. The origin of living matter, its increase and dispersion all over the globe, its marvellous and endless developments and evolutions, and its reactions with its surroundings may all be explained in terms of physics and chemistry. But consciousness and its association with living things will ever remain the mystery it has been and is. |