"aRb" says that "a" stands to "b" in the relation "R", provided mathematically a description of R(a, b)
　[ R(a, b) ≡ f(x, y)].　Thus, if a ≠ b, the ordered pair (a, b) is not the same as the ordered pair (b, a).

　　"Resource" entities are "domain-unordered", "aRb" cannot have for its primary function the apt description of a data structure.　Accordingly, I propose that we should deal not with relations, which are domain-ordered, but with relationships which are their domain-unordered counterparts, and that we should evolve the following rule as a guide for relationship between the two, a and b:

　　1. a ≠ b
　　 (1) resource and resource
　　 (2) resource and event
　　 (3) event and event

　　2. a = b (recursive)

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