OUR LIFE. 43 



movement, Haller gave strong support to the erroneous 

 idea of a specific " vital force " (vis vitalis). 



For more than a century afterwards, from the middle 

 of the eighteenth until the middle of the nineteenth 

 century, medicine and (especially) physiology were 

 dominated by the old idea that a certain number of 

 the vital processes may be traced to physical and 

 chemical causes, but that others are the outcome of a 

 special vital force which is independent of physical 

 agencies. However much scientists differed in their 

 conceptions of its nature and its relation to the 

 " soul," they were all agreed as to its independence of, 

 and essential distinction from, the chemico-physical 

 forces of ordinary "matter "; it was a self-contained 

 force (archceus), unknown in inorganic nature, which 

 compelled ordinary forces into its service. Not only 

 the distinctly physical activity, the sensibility of the 

 nerves and the irritability of the muscles, but even the 

 phenomena of sense-activity, of reproduction, and of 

 development, seemed so wonderful and so mysterious 

 in their sources that it was impossible to attribute 

 them to simple physical and chemical processes. As 

 the free activity of the vital force was purposive and 

 conscious, it led, in philosophy, to a complete teleology ; 

 especially did this seem indisputable when even the 

 "critical" philosopher, Kant, had acknowledged, in 

 his famous critique of the teleological position, that, 

 though the mind's authority to give a mechanical 

 interpretation of all phenomena is theoretically 

 unlimited, yet its actual capacity for such interpreta- 

 tion does not extend to the phenomena of organic 

 life ; here we are compelled to have recourse to a 

 purposive — therefore supernatural — principle. This 

 divergence of the vital phenomena from the mechanical 



