824 THE AMERICAN JOURNAL OF SOCIOLOGY
c) The laws of this mode of collective action are, accordingly, psychological, not merely biological. There is a give-and-take directly from mind to mind; the copying of a model; the con- tagion of feeling; the joint satisfaction arising from united activity. Other individuals enter directly into the psychological and social situation, in the mind of each ; and these others furnish the essential stimulation. Each responds to each through their mental part.
We have here then a mode of psychological solidarity, differ- ent in its origin and nature from the biological solidarity of instinct. Its processes are psychological — those of imitation, suggestion, contagion, spontaneous union in common experience and action. It is only by the recognition of these psychological processes that this mode of solidarity can be properly understood.
3. The Reflective or Social Group Proper. When we come to consider the higher forms of social life, armed with this account of the instinctive and spontaneous forms, we become aware that still other genetic motives and factors come into play. It has been conclusively shown by various writers that there is a difference between cases, on the one hand, in which the indi- vidual is simply carried away by a social current — in which, that is, he is plastic in the hands of the group as just described — and cases, on the other hand, in which he intentionally and voluntarily co-operates with others in the pursuit of intelligent ends.® In the former there is an emotional response to a social suggestion; in the latter, an intelligent judgment made with a view to conse- quences to be attained. The latter mode of co-operation consti- tutes a group that may properly be called "social."
In it we detect, in turn, certain characters which are absent from both the fonns of solidarity already described. These characters we may now point out.
a) These intelligent acts of co-operation cannot be considered as due to either physical or social heredity ; they are not embodied
• This distinction is recognized by many writers ; I may cite the following philosophical and psychological works as representative: Mackensis, Social Phi- losophy; Alexander, Moral Order and Progress; Baldwin, Social and Ethical Interpretations (in this work the general position of this paper is worked out in detail, but not with reference to the problem of solidarity).
