The cost of being cooperative: Details of the effort in processing scalar implicature

A long-standing open question concerns the cost or effort involved in processing scalar implicatures (SIs). When we hear “Some of the boxes are red”, we go beyond the literal meaning of “some” and infer that not all of the boxes are red. According to the Default view [1] hearers compute these kinds of SIs (generalized conversational implicatures) quickly, costlessly, and automatically. In contrast, according to the Relevance Theory view [2], all inferences are costly and only computed if contextually sufficiently relevant.