I need not remind you that such a method is absolutely without bias or partisanship; that it looks upon all religions alike as more or less enlightened expressions of mental traits common to all mankind in every known age.[1] It concedes the exclusive possession of truth to none, and still less does it aim to set up any other standard than past experience by which to measure the claims of any. It brings no new canons of faith or doctrine, and lays no other foundation than that which has been laid even from the beginning until now.

But just there its immediate utility and practical bearings are manifested. It seeks to lay bare those eternal foundations on which the sacred edifices of religion have ever been and must ever be erected. It aims to accomplish this by clearing away the incidental and adventitious in religions so as to discover what in them is permanent and universal. Those sacred ideas and institutions which we find repeated among all the early peoples of the earth, often developing in after ages along parallel lines, will form the special objects of our investigation. The departures from these universal forms, we shall see, can be traced to local or temporary causes, they turn on questions of environment, and serve merely to define the limits of variability of the ubiquitous principles of religion as a psychic phenomenon, wherever we find it.

This is not “theology.” That branch of learning aims to measure the objective reality, the concrete truth, of some one or another opinion concerning God and divine things; while the scientific study of religions confines itself exclusively to examining such opinions as phases of human mental activity, and ascertaining what influence they have exerted on the development of the species or of some branch of it. Therefore it is never “polemic.” It neither attacks nor defends the beliefs which it studies. It confines itself to examining their character and influence by the lights of reason and history.

The methods which we employ in this process of reduction are three in number: 1. The Historic Method; 2. The Comparative Method; 3. The Psychologic Method. A few words will explain the scope of each of these.

The Historic Method studies the history of beliefs and the development of worship. It seeks to discover what influences have been exerted on them by environment, transmission, heredity, and conquest, and to bring into full relief what is peculiar to the tribe or group under consideration, and what is exotic. For in one sense it is true that every nation and tribe, even every man, has his own religion.

Such ethnic traits merit the closest scrutiny. They are so marked and constant as to modify profoundly the history of even the ripest religions. It is quite true, as has been observed by an historian of Christianity, that “there is in every people an hereditary disposition to some particular heresy,”[2] that is, to altering any religion which they accept in accordance with the special constitution of their own minds.

The Comparative Method notes the similarities and differences between the religions of different tribes or groups, and, gradually extending its field to embrace the whole species, endeavors, by excluding what is local or temporal, to define those forms of religious thought and expression which are common to humanity at large.

The Psychologic Method takes the results of both the previous methods and aims to explain them by referring the local manifestations to the special mental traits of the tribe or group, and the universal features to equally universal characteristics of the human mind.

The last, the Psychologic Method, is the crown and completion of the quest; for every advanced student of religion will subscribe to the declaration of Professor Granger, that “all mythology and all history of beliefs must finally turn to psychology for their satisfactory elucidation.”[3] In other words, the laws of human thought can alone explain its own products.