Unfortunately, the method which they generally employ is purely dialectic: they confine themselves to analysing the idea which they make for themselves of religion, except as they illustrate the results of this mental analysis by examples borrowed from the religions which best realize their ideal. But even if this method ought to be abandoned, the problem remains intact, and the great service of philosophy is to have prevented its being suppressed by the disdain of scholars. Now it is possible to attack it in a different way. Since all religions can be compared to each other, and since all are species of the same class, there are necessarily many elements which are common to all. We do not mean to speak simply of the outward and visible characteristics which they all have equally, and which make it possible to give them a provisional definition from the very outset of our researches; the discovery of these apparent signs is relatively easy, for the observation which it demands does not go beneath the surface of things. But these external resemblances suppose others which are profound. At the foundation of all systems of beliefs and of all cults there ought necessarily to be a certain number of fundamental representations or conceptions and of ritual attitudes which, in spite of the diversity of forms which they have taken, have the same objective significance and fulfil the same functions everywhere. These are the permanent elements which constitute that which is permanent and human in religion; they form all the objective contents of the idea which is expressed when one speaks of religion in general. How is it possible to pick them out?

Surely it is not by observing the complex religions which appear in the course of history. Every one of these is made up of such a variety of elements that it is very difficult to distinguish what is secondary from what is principal, the essential from the accessory. Suppose that the religion considered is like that of Egypt, India or the classical antiquity. It is a confused mass of many cults, varying according to the locality, the temples, the generations, the dynasties, the invasions, etc. Popular superstitions are there confused with the purest dogmas. Neither the thought nor the activity of the religion is evenly distributed among the believers; according to the men, the environment and the circumstances, the beliefs as well as the rites are thought of in different ways. Here they are priests, there they are monks, elsewhere they are laymen; there are mystics and rationalists, theologians and prophets, etc. In these conditions it is difficult to see what is common to all. In one or another of these systems it is quite possible to find the means of making a profitable study of some particular fact which is specially developed there, such as sacrifice or prophecy, monasticism or the mysteries; but how is it possible to find the common foundation of the religious life underneath the luxuriant vegetation which covers it? How is it possible to find, underneath the disputes of theology, the variations of ritual, the multiplicity of groups and the diversity of individuals, the fundamental states characteristic of religious mentality in general?

Things are quite different in the lower societies. The slighter development of individuality, the small extension of the group, the homogeneity of external circumstances, all contribute to reducing the differences and variations to a minimum. The group has an intellectual and moral conformity of which we find but rare examples in the more advanced societies. Everything is common to all. Movements are stereotyped; everybody performs the same ones in the same circumstances, and this conformity of conduct only translates the conformity of thought. Every mind being drawn into the same eddy, the individual type nearly confounds itself with that of the race. And while all is uniform, all is simple as well. Nothing is deformed like these myths, all composed of one and the same theme which is endlessly repeated, or like these rites made up of a small number of gestures repeated again and again. Neither the popular imagination nor that of the priests has had either the time or the means of refining and transforming the original substance of the religious ideas and practices; these are shown in all their nudity, and offer themselves to an examination, it requiring only the slightest effort to lay them open. That which is accessory or secondary, the development of luxury, has not yet come to hide the principal elements.[2] All is reduced to that which is indispensable, to that without which there could be no religion. But that which is indispensable is also that which is essential, that is to say, that which we must know before all else.

Primitive civilizations offer privileged cases, then, because they are simple cases. That is why, in all fields of human activity, the observations of ethnologists have frequently been veritable revelations, which have renewed the study of human institutions. For example, before the middle of the nineteenth century, everybody was convinced that the father was the essential element of the family; no one had dreamed that there could be a family organization of which the paternal authority was not the keystone. But the discovery of Bachofen came and upset this old conception. Up to very recent times it was regarded as evident that the moral and legal relations of kindred were only another aspect of the psychological relations which result from a common descent; Bachofen and his successors, MacLennan, Morgan and many others still laboured under this misunderstanding. But since we have become acquainted with the nature of the primitive clan, we know that, on the contrary, relationships cannot be explained by consanguinity. To return to religions, the study of only the most familiar ones had led men to believe for a long time that the idea of god was characteristic of everything that is religious. Now the religion which we are going to study presently is, in a large part, foreign to all idea of divinity; the forces to which the rites are there addressed are very different from those which occupy the leading place in our modern religions, yet they aid us in understanding these latter forces. So nothing is more unjust than the disdain with which too many historians still regard the work of ethnographers. Indeed, it is certain that ethnology has frequently brought about the most fruitful revolutions in the different branches of sociology. It is for this same reason that the discovery of unicellular beings, of which we just spoke, has transformed the current idea of life. Since in these very simple beings, life is reduced to its essential traits, these are less easily misunderstood.

But primitive religions do not merely aid us in disengaging the constituent elements of religion; they also have the great advantage that they facilitate the explanation of it. Since the facts there are simpler, the relations between them are more apparent. The reasons with which men account for their acts have not yet been elaborated and denatured by studied reflection; they are nearer and more closely related to the motives which have really determined these acts. In order to understand an hallucination perfectly, and give it its most appropriate treatment, a physician must know its original point of departure. Now this event is proportionately easier to find if he can observe it near its beginnings. The longer the disease is allowed to develop, the more it evades observation; that is because all sorts of interpretations have intervened as it advanced, which tend to force the original state into the background, and across which it is frequently difficult to find the initial one.