Testing theories of plural meanings.

Area of Science:

• Linguistics
• Developmental Psychology
• Cognitive Science

Background:

• English plural morphology typically triggers a multiplicity inference (e.g., 'giraffes' implies more than one).
• This multiplicity inference disappears in downward-entailing contexts like negation (e.g., 'didn't feed giraffes' implies none).
• Existing theories (ambiguity, implicature, homogeneity) explain this but differ on predictions for specific linguistic contexts and acquisition.

Purpose of the Study:

• To investigate adults' and preschool-aged children's interpretation of English plural morphology.
• To test predictions of different theoretical approaches regarding multiplicity inferences in positive and negative sentences within singular contexts.
• To examine the acquisition of plural meanings and their relationship with scalar implicatures in children.

Main Methods:

• Conducted three experiments involving adults and preschool-aged children.
• Assessed participants' interpretations of positive and negative plural sentences in singular contexts.
• Analyzed responses in relation to established theories of plural morphology and scalar implicatures.

Main Results:

• Participants, including children, distinguished between positive and negative plural sentences in singular contexts.
• Adults assigned different statuses to positive and negative plural sentences.
• Children accepted underinformative positive plural sentences (similar to scalar implicatures) but rejected negative plural sentences more frequently, showing more adult-like behavior in negative contexts.

Conclusions:

• Findings support a scalar implicature approach to multiplicity inferences associated with English plural morphology.
• The results present challenges for ambiguity and homogeneity-based accounts.
• Children's acquisition patterns, particularly their handling of negative plural sentences, provide crucial data for linguistic theory.