One of the most important products of this movement is Sir James Frazer's monumental study The Golden Bough: A Study in Magic and Religion. Frazer collects an immense amount of information from a wide variety of world cultures, including those of ancient Greece and Rome, and attempts to correlate it in order to answer certain basic questions about the nature of primitive religious belief.
In order to compare material that is on the surface so diverse requires that it be translated into a more abstract language. Thus Frazer treats the myth of Dionysus, for example, by focussing on certain key motifs. "The god Dionysus," he writes,
is best known to us as a personification of the vine and of the exhileration produced by the juice of the grape. His ecstatic worship, characterized by wild dances, thrilling music, and tipsy excess, appears to have originated among the rude tribes of Thrace, who were notoriously addicted to drunkenness. Its mystic doctrines and extravagent rites were essentially foreign to the clear intelligence and sober temperament of the Greek race. Yet appealing as it did to that love of mystery and that proneness | to revert to savagery which seems to be innate in most men, the religion spread like wildfire through Greece until the god whom Homer hardly deigned to notice had become the most popular figure of the pantheon. [pp. 386-87 of the abridged edition]Frazer goes on to observe that Dionysus was regarded not only as a god of the vine, but a god of trees in general, and "was believed to have died a violent death, but to have been brought to life again" (p. 388). He is able to compare Dionysus on these terms with other gods (like the Egyptian Osiris, the Phrygian Attis, and the Syrian Adonis) and heroes (the Greek Hippolytus and the Roman Virbius) whose stories feature similar motifs. In this way he develops a theory that derives the human religious impulse from wonder at the natural process of annual, cyclic vegetation.