PREFACE xiii
only upon the quantity and quality of the factual material at our disposal, but also upon the apparatus of concepts and hypotheses which guide our investigations. The difficulty in science is not in finding answers to questions once they have been propounded, but in finding out what questions to ask. In a natural science of society the comparative method takes the place of the experimental method in other sciences and what Claude-Bernard said of the latter is equally true of the former. 'The experimental method cannot give new and fruitful ideas to men who have none; it can serve only to guide the ideas of men who have them, to direct their ideas and to develop them so as to get the best possible results. As only what has been sown in the ground will ever grow in it, so nothing will be developed by the experimental method except the ideas submitted to it. The method itself gives birth to nothing. Certain philosophers have made the mistake of according too much power to method along these lines.'
The factual material available for a comparative study of the political institutions of the simpler societies is inadequate both in quantity and quality. It is to be hoped that the publication of the essays contained in this volume may stimulate other anthropologists to give us similar descriptive studies. The quality of descriptive data, their value for comparative study, depends to a considerable7 extent on how the observer understands the theoretical problems for the solution of which the data he collects are relevant. In science, observation and the selection of what to record need to be guided by theory. In the study of the simpler societies the anthropologist finds that the concepts and theories of political philosophers or economists are unserviceable or insufficient. They have been elaborated in reference to societies of a limited number of types. In their place, the social anthropologist has to make for himself theories and concepts which will be universally applicable to all human societies, and, guided by these, carry out his work of observation and comparison.
In some regions of Africa, it is easy to define what may be called the 'political society'. This is so for the Ngwato, the Bemba, and Ankole, where we find a tribe or kingdom ruled over by a chief or king. But the difficulty that is presented iii other regions is well illustrated by the discussion in Dr. Wagner's essay on the Bantu Kavirondo tribes,3 Something of the same