 Ian Wilson (in Wilson 1979) proposes that there are five possible relations symbolised by “if, … then …” including the reason why reading. Subsequent authors have not adopted this proposal, preferring to focus mainly on three of these relations, each of which bears on questions of necessity and sufficiency. First is the implication relation symbolised by the hook operator, “⊃” or perhaps some relevant implication operator. Such an operator captures some inferential relations as already noted. For example, we saw that from the truth of a conjunction, it can be inferred that each component is true (from “p and q”, we can infer that “p” is true and that “q” is true). Hook, or a relevant implication operator, seems to capture one of the relations encountered in the sea battle case, a relation which can be thought of as holding paradigmatically between bearers of truth values, but can also be thought of in terms of states of affairs. For this relation, we are able to maintain the standard theory’s reciprocity thesis with the limitations already noted.