When we speak, we often mean more than what we say, that is, more than what our utterances literally mean. In these cases, there is a surplus of content which is not expressed explicitly but is implied and, therefore, is part of the conveyed message. An example is when a speaker uses a so-called factive verb, that is, a verb such as know, discover, etc., followed by a that-clause, as in (1):

(1) Jim knows that Sue lives in Rome

A sentence such as (1) conveys implicitly that the content of the that-clause is true: Sue lives in Rome. However, this implication has been recently debated since factive verbs can also be used in contexts where the content of the that-clause is not true, as in (2):

(2) Everyone knew that stress caused ulcers, before two doctors proved that ulcers are caused by bacterial infection (Hazlett 2010)

Interestingly, results from our previous studies suggest that factivity (i.e.whether the content of the that-clause is assumed to be true or not) is audible in the way the speaker pronounces the sentence. In the project we want to confirm this preliminary finding with empirical methods. Following a two-year-long time plan, we intend to record a collection of spoken examples comparable to (2) in the languages Italian and English, analyze them acoustically, and use them in a perception test with human listeners. By providing new experimental data, the project will deepen our understanding of factivity and of how implied meaning is conveyed in communicative contexts.