w. g. stt-:vexsox. 89-(59) 



ence of an "intermediate nature" which, though distinct 

 from the mortal soul or pneuma, was the source of vital 



activity. 



'Plie pneuma was deemed sue]) an important factor in 

 the explanation of vital phenomena, that a school called 

 ' ' Pneumatists " was founded in the first century of our 

 era. 



It was not then known that the arteries contained 

 blood, but they were regarded as the channels through 

 which the jjneuma passed throughout the body ; and this 

 pneuma was to Galen, A. I). 130, identical with the soul. 



For fourteen hundred years pneumatism, under varied 

 forms, was the accepted philosophic belief of the civilized 

 world, and only in the latter part of the sixteenth cen- 

 tury did anatomical study enable Sylvius, Fallopius, 

 Fabricius and Harvey to modify the prevailing belief 

 relative to bodily functions. 



Then it was that Paracelsus sought to explain vital 

 phenomena through the agency of an ' k archpeus ' ' or 

 demon, which, he affirmed, was located in the stomach 

 and presided over the processes of nutrition, separating 

 the useful from the poisonous part of the food. 



Van Helmont adopted the idea of an archseus but 

 thought it an immaterial, though personal force or entity, 

 which "presided over all bodily functions." and gave to 

 each member of the body its own special " vital spirit." 

 The consensus of all these vital spirits produced health, 

 and their disagreement disease. 



Van Helmont "discovered gaseous substances and 

 identified the archauis itself with gas." He proclaimed 

 the existence of a general bond of sympathy throughout 

 the universe, because of the vital spirits which resided in 

 all forms of matter. 



To him an inflammation was the direct result of an ir- 

 ritating ferment sent into the tissues 1 >y the archseus when 

 enraged. Here in a dim way is foreshadowed the later 

 doctrine of "irritability" and "stimulus." 



Descartes regarded the body simply as a complex ma- 

 chine acting under conditions of physical forces, and all 

 the phenomena of life were but the products of their 

 working. The soul, however, was a higher and indepen- 

 dent principle which, located in the pineal gland, made 



