Religion as a second-order generalized concept.

J.Z. Smith's Religion, Religions, Religious is directly relevant to our recent (only?) debate. I'm retyping the last page or so:

As in the eighteenth century, so too in the late twentieth do the issues attending the religious force the definitional question of religion. Two definitions command widespread scholarly assent, one essentially theological, the other anthopological. Paul Tillich, reversing his previous formulation that religion is concern for the ultimate, argued that

religion, in the largest and most basic sense of the word, is ultimate concern... manifest in the moral sphere as the unconditional seriousness of moral demand[,]... in the realm of knowledge as the passionate longing for ultimate reality[,]... in the aesthetic function of the human spirit as the infinite desire to express ultimate meaning." [Religion is not a] special function of man's spiritual life, but the dimension of depth in all its functions.

As Tillich's earlier concern with topics such as idolatry and the demonic should suggest, this is not as generous and open ended a definition as might seem to be implied. Tillich has in fact provided a definition of the religious, as a dimension (in his case, the ultimate, unconditioned aspect) of human existence. This is explicit in Christian's reformulation: "Someone is religious if in his universe there is something which (in principle) all other things are subordinated." ...If one removes Tillich's and Christian's theological criteria... then it becomes difficult if not impossible to distinguish religion from any other ideological category. This would be the direction that Ninian Smart points to in suggesting that religion be understood as "worldview," with the latter understood as a system "of belief which, through symbols and actions mobilize[s] the feelings and wills of human beings."

The anthropological definition of religion that has gained widespread assent among scholars of religion, who both share and reject its functionalist frame, is that formulated by Melford E. Spiro, "an" institution consisting of culturally patterned interaction with culturally postulated superhuman beings." This definition requires acceptance of a broad theory of cultural creation... and places human activities or institutions as the summum genus and religion as a subordinate taxon. This is made plain in Spiro's formulation that "religion can be differentiated from other culturally constituted institutions by virtue only of its reference to superhuman beings." Subsequent reformulations by scholars of religion have tended either to remove this subordination or to substitute "supernatural" for "superhuman."

It was once a tactic of students of religion to cite the appendix of James H. Leuba's Psychological Study of Religion, (1912), which lists more than fifty definitions of religion, to demonstrate that "the effort to define religion in short compass is a hopeless task" (King, 1954). Not at all! The moral of Leuba is not that religion cannot be defined, but that it can be defined, with greater or lesser success, more than fifty ways. Besides, Leuba goes on to classify and evaluate his list of definitions. "Religion" is not a native term; it is a term created by scholars for their intellectual purposes and therefore is theirs to define. It is a second-order, generic concept that plays the same role in establishing a disciplinary horizon that a concept such as "language" plays in linguistics or "culture" plays in anthropology. There can be no disciplined study of religion without such a horizon.

UPDATE: Grammar corrected, thank you Laura. Inexcusable