598 THE POPULAR SCIENCE MONTHLY. 



which it fulfils in excess some single vital need, only if its other vital 

 needs are fulfilled for it by other parts that have meanwhile under- 

 taken other special activities. One portion of a living aggregate can- 

 not devote itself exclusively to the respiratory function, and cease to 

 get nutriment for itself, unless other portions, that have become ex- 

 clusively occupied in absorbing nutriment, give it a due supply. That 

 is to say, there must be exchange of services. Organization in an in- 

 dividual creature is made possible only by dependence of each part on 

 all, and of all on each. Now, this is obviously true also of social 

 organization. A member of a primitive society cannot devote himself 

 to an order of activity which satisfies one only of his personal wants, 

 thus ceasing the activities required for satisfying his other personal 

 wants, unless those, for whose benefit he carries on his special activity 

 in excess, supply him with the benefits of their special activities. If 

 he makes weapons instead of continuing a hunter, he must be supplied 

 with the produce of the chase on condition that the hunters are supplied 

 with his weapons. If he becomes a cultivator of the soil, no longer 

 defending himself, then he must be defended by those who have become 

 specialized defenders. That is to say, mutual dependence of parts is 

 essential for the commencement and advance of social organization, as 

 it is for the commencement and advance of individual organization. 



Even were there no more to be pointed out, it would be clear 

 enough that we are not here dealing with a figurative resemblance, 

 but with a fundamental parallelism in principles of structure. We 

 have but just begun to explore the analogy, however. The further we 

 inquire, the closer we find it to be. For what, let us ask, is implied by 

 mutual dependence by exchange of services ? There is implied some 

 mode of communication between mutually-dependent parts. Parts 

 that perform functions for one another's benefit must have appliances 

 for conveying to one another the products of their respective func- 

 tions, or for giving to one another the benefits (when these are not 

 material products) which their respective functions achieve. And ob- 

 viously, in proportion as the organization becomes high, the appliances 

 for carrying on the intercourse must become involved. This we find 

 to hold in both cases. In the lowest types of individual organisms, 

 the exchange of services between the slightly-differentiated parts is 

 effected in a slow, vague, inefficient way, by an irregular diffusion of 

 the nutrient matters jointly elaborated, and by an irregular propaga- 

 tion of feeble stimuli, causing a rude coordination in the actions of the 

 parts. It is thus, also, with small and simple social aggregates. No 

 definite arrangements for interchanging services exist, but only in- 

 definite ones. Barter of products food, skins, weapons, or what not 

 takes place irregularly between individual producers and consumers 

 throughout the whole social body: there is no trading or distributing 

 system, as, in the rudimentary animal, there is no vascular system. 

 So, too, the social organism of low type, like the individual organism 



