This change marks the transformation of sociology from a philosophy of history to a science of society. The steps in this transition are periods in the history of the science, that is: 1. The period of Comte and Spencer; sociology, conceived in the grand style, is a philosophy of history, a "science" of progress (evolution). 2. The period of the "schools"; sociological thought, dispersed among the various schools, is absorbed in an effort to define its point of view and to describe the kinds of facts that sociology must look for to answer the questions that sociology asks. 3. The period of investigation and research, the period into which sociology is just now entering. Sociological research is at present (1921) in about the situation in which psychology was before the introduction of laboratory methods, in which medicine was before Pasteur and the germ theory of disease. A great deal of social information has been collected merely for the purpose of determining what to do in a given case. Facts have not been collected to check social theories. Social problems have been defined in terms of common sense, and facts have been collected, for the most part, to support this or that doctrine, not to test it. In very few instances have investigations been made, disinterestedly, to determine the validity of a hypothesis. Charles Booth's studies of poverty in London, which extended over eighteen years and were finally embodied in seventeen volumes, is an example of such a disinterested investigation. It is an attempt to put to the test of fact the popular conception of the relation between wages and welfare. He says: My object has been to attempt to show the numerical relation which poverty, misery, and depravity bear to regular earnings and comparative comfort, and to describe the general conditions under which each class lives. If the facts thus stated are of use in helping social reformers to find remedies for the evils which exist, or do anything to prevent the adoption of false remedies, my purpose is answered. It was not my intention to bring forward any suggestions of my own, and if I have ventured here and there, and especially in the concluding chapters, to go beyond my programme, it has been with much hesitation. With regard to the disadvantages under which the poor labour, and the evils of poverty, there is a great sense of helplessness: the wage earners are helpless to regulate their work and cannot obtain a fair equivalent for the labour they are willing to give; the manufacturer or dealer can only work within the limits of competition; the rich are helpless to relieve want without stimulating its sources. To relieve this helplessness a better stating of the problems involved is the first step.... In this direction must be sought the utility of my attempt to analyze the population of a part of London.[44]