With the essentialist approach in mind--an approach adopted by those who presume religions house a core experience or fundamental trait that sets them apart from all other aspects of human behavior--we can contrast it with the functionalist approach. Consider the thing that appears in many classrooms: a lectern behind which the professor stands while teaching. What is the difference between a lectern and a pulpit? Or, to put it another way, how do we know which name to give to which object? Is there some key feature that we can recognize to distinguish between the two? This does not seem likely, because the same physical object could easily be identified as both. So what makes a pulpit a pulpit, and not a lectern (not to mention a podium)?

For the functionalist scholar, there is no one essential feature that unites all things we call "lecterns" and thereby distinguishes them from those things known as "pulpits." Instead, the context into which something is found, the expectations placed upon it by its users, and, most importantly perhaps, the purpose it serves and the needs it fills are what cause things to be defined as this and not that. Functionalists, then, are people interested in asking what something does rather than what it is.

For early twentieth-century scholars, it was this shift from speculating on universal, non-empirical qualities and affectations to observing the role of local, historical context and empirical effects that signified the development of what they considered to be a truly scientific (i.e., historical, documentable) study of religion, in distinction from a well-meaning but, nonetheless, theologically-motivated study of religion's enduring value or groundless speculations on its pre-historic origins and evolutionary development. For example, consider that group of scholars already mentioned, a group which predated the rise of functionalism: the Intellectualists. This group of nineteenth-century anthropologists (or perhaps we should refer to them as the precursors to the field today known as anthropology) were very interested in origins--to explain something, they assumed, required one to account for its original state and its change over time.

Take Tylor's theory of Animism, which we have already mentioned, but only briefly; to explain why people believe in spiritual beings Tylor performed what we might call a thought experiment. He asked his readers to imagine an evolutionarily early human being waking from a dream. Unlike modern people, who have a fairly complex understanding of the difference between being awake and asleep, this "savage philosopher," as Tylor termed him, was not aware of just what a dream was. However, much like us, he was profoundly interested in accounting for anomalies in his environment--it's just that he did not have the stock of scientific methods available as do you and I. Nonetheless, using rudimentary methods, Tylor concludes that the early human must have arrived at an explanation to account for the odd thing of "seeing" himself elsewhere or why he was able to "see" long dead ancestors (all of which was during his dream). Concluding that there must be something that outlives the body, that can depart and return to the body--call it a soul, if you will--struck Tylor as a pretty sensible way for such an early human being to account for such an odd experience.

Of course, few today would classify themselves as Intellectualists in quite this way, for there are a number of problems with this form of scholarship. To name but one, consider Tylor's conclusion: the "savage philosopher" explained his experience as the result of his having a soul. But is Tylor's theory of animism correct? To answer this question, we need to determine a set of criteria so that we can judge whether Tylor's theory of animism is persuasive or accurate. But short of inventing time travel, to allow us to be present when the early human awoke, so that we could observe him, we cannot really come up with a way to test Tylor's theory. In fact, some would question whether Tylor even had a theory, as opposed to a untestable speculation, premised on the assumption that early humans must have behaved in a childlike manner, solving problems as do contemporary children (after all, nineteenth-century scholars often refered to early humanity as "the childhood of the species"). To make a long story short, the problem with explaining contemporary events in terms of their origins is that the origin is long gone and remains only as a product of speculations that project contemporary assumptions backward in time. As such, one guess might be as good as another because the standard against which one measures the guesses--the actual origin--cannot be retrieved.

Given just how troublesome it is to try to explain current events in light of their origins--such as answering a question concerning why people throw spilt salt over their shoulders by saying, "Well, a long time ago..."--one can see the appeal of shifting the ground considerably and, instead of speculating on an original essence, trying instead to account for the contemporary purpose something serves or the need it fulfills. In the early twentieth century, functionalists--who no doubt benefit greatly from earlier generations of scholars intent on explaining religion by means of appeals to its historical origins (such as David Hume's work)--made just this switch, seeing their Intellectualist predecessors as doing something other than science. Their focus on the contemporary and the observable made their theories testable, and, as they argued, thus truly scientific.

Today, functionalists who study religion owe much to such early writers as:

Karl Marx (1818-1883), whose materialist, political economy theorized religion as a social pacifier that both deadened the oppressed people's sense of pain and alienation while simultaneously preventing them from doing something about their lot in life since ultimate responsibility was thought to reside with a being who existed outside history and who would compensate for this-worldly suffering and exploitation in the life to come. Religion, for a Marxist scholar, functions to reproduce the status quo by distracting attention from the actual source of conflict.

Emile Durkheim (1858-1917), whose sociological study of religion has already been mentioned, understood intertwined sets of beliefs and practices to enable individuals to form the idea of a common social identity; for Durkheim, claims about religion were actually coded claims about the social group since the practices we call religious are none other than members' efforts to experience the group (for example, through performing common rituals). Religion, for a social theorist in Durkheim's tradition, functions to build and retain group identity.

Sigmund Freud's (1856-1939) early psychological studies led him to liken public ritual to private obsessive compulsive disorders, and to compare collective myths to the psychological role dreams play in helping an individual to express symbolically anti-social anxieties in a manner that does not threaten their place within the group. In light of his work, some today argue that religion functions to provide a venue for satisfying anti-social urges, doing so in a tightly controlled setting, such as the ritual of sacrifice that we seem to find the world over--a ritual that may very well prevent violence from spilling over into all of social life.

Current scholarship is pressing such classic work in entirely new directions, such as drawing on materialist scholarship and semiotic theory to study the political function of myth (e.g., Bruce Lincoln); using a social theory to account for such things as the beginnings of Christianity (e.g., Burton Mack and Bill Arnal); and drawing on economic models of how shoppers choose among alternatives, to develop a rational choice theory of religion (e.g., Rodney Stark).