Form and function: Optional complementizers reduce causal inferences.

Joseph Tyler,Hannah Rohde,Katy Carlson

doi:10.5334/gjgl.134

Abstract

Many factors are known to influence the inference of the discourse coherence relationship between two sentences. Here, we examine the relationship between two conjoined embedded clauses in sentences like The professor noted that the student teacher did not look confident and (that) the students were poorly behaved. In two studies, we find that the presence of that before the second embedded clause in such sentences reduces the possibility of a forward causal relationship between the clauses, i.e., the inference that the student teacher’s confidence was what affected student behavior. Three further studies tested the possibility of a backward causal relationship between clauses in the same structure, and found that the complementizer’s presence aids that relationship, especially in a forced-choice paradigm. The empirical finding that a complementizer, a linguistic element associated primarily with structure rather than event-level semantics, can affect discourse coherence is novel and illustrates an interdependence between syntactic parsing and discourse parsing.

Highlights

Interpreting a sentence of natural language depends on the integration of a number of different levels of structure and meaning
The ratings on the unambiguous filler items confirm that the 37 participants we included in the main analysis paid attention to the task and understood the direction of the rating scale: unambiguously causal fillers received higher causal ratings (4.70) than unambiguously non-causal fillers (2.55), and model comparison confirmed that causality ratings were better captured by a model containing a factor for discourse marker because-vs-despite (ß = –5.17, p < 0.001)
Causal order was a significant predictor of sentence selection (ß = 2.05, p < 0.001): in the forward-causality condition, participants preferred the version with that 60% of the time, and, as predicted, in the reverse-causality condition that preference increased to 84%

Summary

Introduction

Interpreting a sentence of natural language depends on the integration of a number of different levels of structure and meaning. Strong claims have been made regarding the centrality of causal relations to discourse interpretation: e.g., Trabasso and van den Broek’s (1985) emphasis on explanatory inferences in text understanding and Sanders’ (2005) causalityby-default hypothesis. Sanders argues that causal connections are processed more (Mak & Sanders 2012) and serve as an interpretational default (Sanders 2005), marshaling evidence that causal interpretations are assigned faster than non-causal alternatives (Sanders & Noordman 2000; Louwerse 2001), even though they are acquired later (Bloom et al 1980; Evers-Vermeul 2005) Added evidence for this view comes from the relative

Methods

Results

Conclusion