 We should also note that Anderson was famous as a founding figure in  relevance logic,  and along with using strict implication, \(\Box(p \rightarrow q)\), he also explored the use of a relevant (and thus neither material nor strict) form of implication, \(\Rightarrow\), to express the reduction as: \(\OB p \eqdf \neg p \Rightarrow  s\).[40]  (A bit more on this can be found within the entry on  Mally’s deontic logic.  See further references there.) This alternative reflects the fact that there is an issue in both Kanger’s and Anderson’s strict necessitation (or entailment) approaches of just what notion of “necessity” is involved in claiming that meetings all normative demands (or avoiding the sanction) in some sense necessitates \(p\).