PRESENT PROBLEMS OF PHYSIOLOGY 417 



history of other sciences whose field of work has presented appar- 

 ently less formidable difficulties. 



In what may be termed the golden period of physiology, that is, the 

 latter two thirds of the nineteenth century, the period during which 

 the subject became established definitively as an experimental science, 

 the rich and abundant harvest of facts gathered by the first workers 

 who adopted exclusively experimental methods awoke enthusiasm 

 and brightest anticipations. The workers in physiology were ani- 

 mated by a confident belief that their science was on the highroad to 

 a successful solution of the nature and properties of living matter. 

 Now, however, at the beginning of the twentieth century, one hears 

 frequently the voice of dissatisfaction and criticism. Although the 

 workers are more numerous, and the methods and appliances are more 

 complete, the harvest of facts is not so rich nor so significant. There- 

 fore to many it would seem that the methods used are at fault; there 

 is need at least for a new point of view. It requires but little reflection 

 to become convinced that some of the implied or expressed criticism 

 directed toward recent work in physiology is unjust and is founded 

 upon a misconception of its true nature and development. I refer 

 particularly to the belief so frequently expressed that much of the 

 current investigation in physiology is sterile as regards its immediate 

 applicability to practical medicine, and the further statement that the 

 subject itself has become isolated in a measure from the other bio- 

 logical sciences. 1 I do not contest the accuracy of these statements, 

 but both results must be regarded as a necessary outcome of the nor- 

 mal and healthy development of the science of physiology. The general 

 history of physiology is known to us all; it is not necessary to enter 

 into details. It arose out of medicine and developed in intimate rela- 

 tions with the study of anatomy. But even in its earliest history its 

 most significant results were obtained by the use of the experimental 

 method, and in the nineteenth century its separation from the purely 

 observational sciences was clearly recognized. The establishment of 

 physiology as an experimental science is usually attributed to Jo- 

 hannes Miiller and his pupils or their contemporaries who fell under 

 his influence. But as I read its history, its modern characteristics, 

 whether for good or for evil, owe their origin as much to the French 

 as to the German school. Johannes Miiller himself was not preeminent 

 as an experimenter, he made use of anatomical rather than physio- 

 logical methods; but his contemporary Magendie was a typical modern 

 physiologist, and whatever may have been the extent of his personal 

 influence during life, there can be no question that his methods of 

 work and his points of view are the ones that were subsequently 



1 Meltzer, Vitalism and Mechanism in Biology and Medicine, Science, vol. xix, 

 p. 18, 1904. Verworn, Einleitung, Zeitschrift fur Allgemeine Physiologic, i, p. 1, 

 1902. 



