RELATION OF PLANT PHYSIOLOGY TO OTHER SCIENCES. 429 



introduced by botanists, but originated in practical life and passed 

 over from the popular vocabulary into our science. 



The first demonstrable beginnings of plant physiology we find among 

 the Greek philosophers, chiefly Aristotle and Theophrastus. But in 

 these beginnings there was no developmental capacity. In our induc- 

 tive developmental period it was necessary to lay a new foundation for 

 the doctrine of plant life. The Englishman, Stephen Hales, in the 

 beginning of the eighteenth century, was undoubtedly the founder 

 of plant physiology in general, and especially the founder of phys- 

 ical plant physiology, while the commencement of chemical plant 

 physiology is to be referred to the Hollander, Ingenhouss. Ingenhouss 

 is closely identified with us in this regard, that for years he resided in 

 Vienna as physician of the Empress Maria Theresa and of Emperor 

 Joseph II. Some of his first contributions to plant physiology were 

 worked out in Vienna — a fact little known. Later, until the middle of 

 this century, the science was advanced by investigators of French 

 nationality, foremost the Swiss investigator, De Saussure. At the 

 present time, all civilized nations, the Japanese not excluded, take 

 part in the advancement in this field. But if in our time names like 

 De Saussure and Boussingault stand as towering monuments and the 

 teachings of Darwin cease not to iufluence our physiological concep- 

 tions, there have been for many decades German plant physiologists 

 who stood not simply as compeers of their French and English col- 

 leagues, but without exaggeration one may venture to say that German 

 investigators have assumed the leading role in the solution of the 

 most important questions. 



The present developmental period in natural sciences, so rich in 

 unprecedented results, is characterized by the inductive method of 

 research and by the principle of the division of labor. It required 

 thousands of years to show mankind that the experience of all knowl- 

 edge takes root, and that the human mind, with its limitations, despite 

 the genius of occasional great men, can only by the combined work of 

 many, each deep in his narrow specialty, arrive at the solution of the 

 great problems of science. As a consequence, we see in all fields of 

 research the modern socialism of scientific progress vanquishing the 

 intellectual giants of the olden time. 



The objections to the principle of the division of labor in behalf of 

 the mental stage of the individual are well known. These are grad- 

 ually disappearing, and I will leave them without discussion. But for 

 the development of science all of the weaknesses and failures resulting 

 from this jDrinciple will be eradicated, as I shall later demonstrate by 

 certain examples at hand. 



In the realm of botany the division of labor brought about first a 

 separation of descriptive botany from the studies directed toward gen- 

 eral morphology and physiology, which latter, reenforced in a measure, 

 placed themselves in rather sharp opposition to the descriptive side. 



