Over-informative children: Production/comprehension asymmetry or tolerance to pragmatic violations?

It has been proposed that children may fail to comprehend pragmatic aspects of meaning, even though they have little difficulty producing pragmatically appropriate utterances as speakers. A novel account, the pragmatic tolerance hypothesis, predicts that in certain cases children are in fact pragmatically competent both as speakers and as comprehenders and what develops with age is their metalinguistic awareness about accepting or rejecting pragmatically infelicitous utterances as comprehenders. In this paper we focus on pragmatic violations due to over-informativeness and report an investigation into English-speaking 5-year-old children's and adults' production and evaluation of referring expressions. Like adults, children do not over-inform as speakers but unlike adults, child comprehenders do not reject over-informative utterances when given a binary judgment choice. However, when given a magnitude estimation scale which allows for intermediate responses, child comprehenders do penalise over-informative utterances and rate them lower than optimal ones. The findings support the pragmatic tolerance hypothesis. By comparing over-informativeness to under-informativeness and other cases of pragmatic inferencing we propose a set of constraints that predict which pragmatic violations child comprehenders could be tolerant towards.