LUDWIG AND MODERN PHYSIOLOGY. 



By J. Btjrdon- Sanderson. 



I. INTRODUCTION. 



The death of any discoverer — of anyone who has added largely to 

 the sum of human knowledge — affords a reason for inquiring what his 

 work was and how he accomplished it. This inquiry has interest even 

 when the work has been completed in a few years, and has beeu 

 limited to a single line of investigation — much more when the life has 

 been associated with the origin and development of a new science and 

 has extended over half a century. 



The science of physiology, as we know it, came into existence fifty 

 years ago, with the beginning of the active life of Ludwig, in the same 

 sense that the other great branch of biology, the science of living beings 

 (ontology), as we now know it, came into existence with the appearance 

 of the " Origin of Species." In the order of time physiology had the 

 advantage, for the new physiology was accepted some ten years before 

 the Darwinian epoch. Notwithstanding, the content of the science is 

 relatively so unfamiliar, that before entering on the discussion of the 

 life and work of the man who, as I shall endeavor to show, had a larger 

 share in founding it than any of his contemporaries, it is necessary to 

 define its limits and its relations to other branches of knowledge. 



The word physiology has in modern times changed its meaning. It 

 once comprehended the whole knowledge of nature. Now it is the name 

 for one of the two divisions of the science of life. In the progress of 

 investigation the study of that science has inevitably divided itself 

 into two : ontology, the science of living beings; physiology, the science 

 of living processes, and thus, inasmuch as life consists in processes, of 

 life itself. Both strive to understand the complicated relations and 

 endless varieties which present themselves in living nature, but by 

 different methods. Both refer to general principles, but they are of a 

 different nature. 



To the outologist, the student of living beings, plants, or animals, 

 the great fact of evolution, namely, that from the simplest beginning 

 our own organism, no less than that of every animal and plant with its 



1 Founded upon a lecture delivered at the Royal Institution, January 24, 1896. 

 Printed in Science Progress, Vol. V, No. 25, 1896, pages 1-21. 



365 



