This Article first discusses the judicial deliberations upon the definition of religion. That discussion adopts a chronological sequence because, in legal matters, that is the one that counts.

It can be a tedious, but not particularly difficult task to summarize the legal struggle to define religion. The strategy applied to evaluate the product of that struggle is intellectual triangulation, whereby bearings from two fixed positions are used to specify that of that third. By analogy, the correct definition of "religion" can be identified by finding where the legal efforts intersect with an independent sighting of the same target. Where this intersection occurs, there is the "spot" where a satisfying, usable definition is most likely to be found.

The independent discipline selected for this purpose is anthropology. The third section of this Article will provide a review of this field's attempts to define religion. The chronological outline of legal discussion will contrast with the thematic pattern in this anthropological review. A chronological order here would obscure patterns, not reveal them.

The fourth section will then directly compare the results of the two preceding discussions, and reveal that they intersect at a functional definition of religion: religion is to be identified by the need it fulfills. Specifically, the heart of religion is its response to the existential concerns of the individual. The final section will offer a definition that conforms to these results.