2 SCIENCE PROGRESS. 



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 consist 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 Ontologist, 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 infinite complication of 

 parts and powers, unfolds the plan of its existence — taken 

 with the observation that that small beginning was, in all 

 excepting the lowest forms, itself derived from two parents, 

 equally from each — is the basis from which his study and 

 knowledge of the world of living beings takes its departure. 

 For on these two facts — Evolution and Descent — the ex- 

 plorer of the forms, distribution and habits of animals and 

 plants has, since the Darwinian epoch, relied with an ever- 

 increasing certainty, and has found in them the explanation 

 of every phenomenon, the solution of every problem relating 

 to the subject of his inquiry. Nor could he wish for a more 

 secure basis. Whatever doubts or misgivings exist in the 

 minds of " non-biologists " in relation to it, may be attributed 

 partly to the association with the doctrine of Evolution of 

 questions which the true naturalist regards as transcen- 

 dental ; partly to the perversion or weakening of meaning 

 which the term has suffered in consequence of its introduc- 

 tion into the language of common life, and particularly to 

 the habit of applying it to any kind of progress or improve- 

 ment, anything which from small beginnings gradually 

 increases. But, provided that we limit the term to its 

 original sense — the Evolution of a living being from its 

 germ by a continuous, not a gradual process — there is no 



