Incremental distinguishability of subject and object

The subject and the object in a transitive clause should be distinguishable. We discuss five different ways in which distinguishability can be obtained: (i) case morphology, (ii) agreement, (iii) selectional criteria of the verb, (iv) word order, and (v) prominence, in particular animacy. We argue that these different sources of information can be viewed as violable and potentially conflicting constraints that play an important role in the incremental process of interpretation. We propose a new model of incremental optimization of interpretation and argue that we can thus account for the findings of several on-line studies in which distinguishability was manipulated.