Psychological moments may arise in any social situation, but they occur more frequently in a society which has acquired a high state of mobility. They occur more frequently in a society where education is general, where railways, telegraph, and the printing press have become an indispensable part of the social economy. They occur more frequently in cities than in smaller communities. In the crowd and the public every moment may be said to be “psychological.”

Crisis may be said to be the normal condition on the exchanges. What are called financial crises are merely an extension of this critical condition to the larger business community. Financial panics which sometimes follow upon financial crises are a precipitate of this critical condition.

The fascinating thing about the study of crises, as of crowds, is that in so far as they are in fact due to psychological causes, that is, in so far as they are the result of the mobility of the communities in which they occur, they can be controlled. The evidence for this is the fact that they can be manipulated, and there is abundant evidence of manipulation in the transactions of the stock market. The evidence for the manipulation of crowds is less accessible. Labor organizations have, however, known how to develop a pretty definite technique for the instigation and control of strikes. The Salvation Army has worked out a book of tactics which is very largely devoted to the handling of street crowds; and professional revivalists, like Billy Sunday, have an elaborate technique for conducting their revivals.

Under the title of collective psychology much has been written in recent years in regard to crowds and kindred phenomena of social life. Most that has been written thus far has been based upon general observation and almost no systematic methods exist for the study of this type of social organization. The practical methods which practical men like the political boss, the labor agitator, the stock-exchange speculator, and others have worked out for the control and manipulation of the public and the crowd furnish a body of materials from which it is possible to make a more detailed, a more intimate study of what may be called, in order to distinguish it from that of more highly organized groups, collective behavior.

The city, and particularly the great city, in which more than elsewhere human relations are likely to be impersonal and rational, defined in terms of interest and in terms of cash, is in a very real sense a laboratory for the investigation of collective behavior. Strikes and minor revolutionary movements are endemic in the urban environment. Cities, and particularly the great cities, are in unstable equilibrium. The result is that the vast casual and mobile aggregations which constitute our urban populations are in a state of perpetual agitation, swept by every new wind of doctrine, subject to constant alarms, and in consequence the community is in a chronic condition of crisis.

What has been said suggests first of all the importance of a more detailed and fundamental study of collective behavior. The questions which follow will perhaps suggest lines of investigation that could be followed profitably by students of urban life.

What is the psychology of crisis? What is the cycle of events involved in the evolution of a crisis, political or economic?

To what extent may the parliamentary system, including the electoral system, be regarded as an attempt to regularize revolution and to meet and control crises?

To what extent are mob violence, strikes, and radical political movements the results of the same general conditions that provoke financial panics, real estate booms, and mass movements in the population generally?

To what extent are the existing unstable equilibrium and social ferment due to the extent and speed of economic changes as reflected in the stock exchange?