PROPOSITIONS. 81 



to trace certain of the phenomena presented by the life force 

 in its relations to matter, with the end in view of elucidating 

 this difficult point. In this direction, as it seems to me, we 

 are most likely to find a satisfactory explanation for some of 

 the teachings of experiment that have seemed difficult to 

 understand. In these brief lectures, however, we can only 

 glance at the principal points necessarily involved in a com- 

 plete discussion of the subject. 



The phenomena that we will now review will be Digestion, 

 Absorption, Nutrition, and the Formation of Waste Products 

 in the several forms of life ; after which we will study briefly 

 the relation which the changed forms of matter, produced by 

 the physiological activity of micro-organisms, may hold to 

 the production of disease. This is necessarily a biological 

 study. 



DIGESTION. 



Digestion is a process of solution and chemical reorganiza- 

 tion of food material, by which it is fitted for reception by the 

 life force, or is brought within the sphere of chemico-vital 

 influences. The material, when thus prepared, is conveyed 

 within the organism by absorption or osmosis. Digestion 

 and absorption are the admitted forerunners of all nutritive 

 processes the initial steps by which nutrition is rendered 

 possible. This is true of all the varied forms in which the 

 life force is manifest, from the most minute micrococcus to 

 man. There are substances made use of by the life force 

 without digestion previous to absorption, but every living 

 thing is provided with this mode of food preparation. 



PROPOSITIONS. 



1st. All digestion is accomplished by soluble ferments, 

 elaborated by the organism, whether this digestion be accom- 

 plished in a stomach, alimentary canal, or elsewhere. 



