 Example (14) is a special case in that either the effects or the effort are equal between alternative contributions. To know what is maximally relevant in other cases, a particular function of effects and effort must be specified (Hinkelman 1987). Sperber and Wilson specify one when describing the theory of cognition on which they ground their theory of communication. “Our claim is that all human beings automatically aim at the most efficient information processing possible” (Sperber &amp; Wilson 1986a: 49). “Efficiency in cognition … involves processing inputs that offer the best possible cost/benefit ratio at the time”(Wilson &amp; Sperber 2012:  62).[53]  Selecting this function and formulating a principle in the style of Grice’s yields: