33^ Organic Nature's Riddle 



action, processes of nutrition, processes of repair, and processes 

 of individual development, by instinct — using this term in 

 a wide analogical sense. For we know the wonderful action 

 and nature of instinct as it exists in our own human activity, 

 standing, as it were, at the head of the various unconsciously 

 intelligent vital processes. These processes seem to me to 

 be all diverse manifestations of what is fundamentally one 

 kind of activity. Of these manifestations, instinctive action 

 is the best type, because by it we can, to a certain extent, 

 understand the others, whereas none of the others enable 

 us to understand instinct. 



A thoroughly mechanical conception of nature is the 

 scientific ideal of a very large and a very influential school 

 of thinkers,! and the goal towards which they strive. In 

 so striving they follow the lead of the earliest of modern 

 philosophers, Descartes, who would probably have felt no 

 small satisfaction could he have foreseen that the doctrine 

 of animal automatism would be so eloquently advocated 

 in the nineteenth century, as well as that of a mechanical 

 evolution of new species of animals and plants. 



Evidently the last-mentioned conception was necessary 

 to render the mechanical theory complete. As long as men 

 believed in the action of any mysterious intelligence hidden 

 in nature, and working through it in specific evolution 

 towards foreseen and intended ends, a mechanical conception 

 of nature was obviously impossible. But no less impossible 



1 Thus Kirchhoff has said {Prorectoratsrede ; Heidelberg, 1865), ' The 

 highest object at which the natural sciences are constrained to aim is the 

 reduction of all the phenomena of nature to mechanics ' ; and Helmholtz 

 has dieclaxedi {Popular- Wissenschaftliche Vortrdge, 1869), 'The aim of the 

 natural sciences is to resolve themselves into mechanics. ' Wundt observes 

 (Lehrhuch der Physiologic des Menschen), 'The problem of physiology is a 

 reduction of vital phenomena to general physical laws, and ultimately to the 

 fundamental laws of mechanics ' ; while Haeckel tells (Freie Wissenschaft 

 und freie Lehre) that ' all natural phenomena, without exception, from the 

 motions of the celestial bodies to the growth of plants and the consciousness 

 of men, ... are ultimately to be reduced to atomic mechanics.' 



