8 10 THE AMERICAN JOURNAL OF SOCIOLOGY
a part of the body, or in the entire body which resists. In soci- eties it arises from extensive experiences of the group, from pressure exercised in consequence of, and inevitably upon other societies, or even from simple physical obstacles forming a resist- ance. In relation to this primordial consciousness, it is necessary to attribute the highest importance to two functions : the pres- ervation of the individual and of the species. Every other function is subordinate to these. Each of these functions deter- mines whether the habits of the individual will be solitary or social, or partly solitary and partly social. Sociability can begin to assert itself only when there is produced among the individ- uals a stronger tendency to co-operate by means of the first favorable variation in the structure and activity through the impression and perception of an external physical and social resistance. This tendency will be increased by the survival of the better-endowed persons and groups, whose actions will be better fitted for the preservation of the species. The strongest and most durable societies will be those which, under these con- ditions, can best adjust their efforts to their energies, and on the other side resist the external forces. These reciprocal limits are the fundamental psychical factors of the theory of political boundaries. Again, psychical laws, both individual and collect- ive, limit the movements and structure of men and societies, as over against the resistances the pressure from the outside. Between the pressure and the effort there is established a bal- ance a limit. Within the societies themselves an analogous phenomenon is accomplished ; the presence alone of other like individuals in the group produces mental states of sociability by the fact of resistance ; that is to say, the limits that one individ- uality imposes upon another. Individuals are forced to adjust themselves to one another. In a large crowd one is pressed against others and forced to go with the current or remain in one place. From this common life arises a common consciousness. Their origin is undoubtedly due to the sensation and perception of a resistance and of a proportional effort.
Outside the group this perception gives place to the fixation of a boundary ; within the group, chiefly to a common effort, to
