A linguist ready to take risks
How do we humans understand linguistic content? That sense is not the outcome just of single words is presumably common knowledge. Formal semantics investigate the role played by grammar in imparting meaning. Professor Thomas Ede Zimmermann and his team aim now to investigate the underlying theoretical principles by means of a critical analysis of what is known as the "propositionalist hypothesis". This hypothesis assumes that any reference to linguistic content is ultimately based on clausal embedding in grammar. More liberal intensionalist approaches, by contrast, build on the assumption that information content in principle corresponds to all types of expression. "We anticipate that the propositionalist hypothesis – depending on how precisely it is defined – will prove either to be trivial for formal reasons or empirically inadequate," says Zimmermann. Ultimately, the aim is also to find alternatives to propositionalism. Whether this can be achieved remains to be seen. The German Research Foundation has placed a total budget of € 1.25 million at the project's disposal up until the end of 2022.
What plays an especially important role in the project is the difference between extensional and intensional grammatical constructions. Extensional constructions are characterized by the fact that co-referring names and descriptions within them can be substituted without compromising the accuracy of the overall statement. Relative clauses, which another of Zimmermann's research groups has been studying in depth for many years, are an example of such extensional constructions. For example, the sentence 'The conman, who is from Wiesbaden, is on the run' cannot become incorrect if the word 'Wiesbaden' is replaced by 'Hessen's capital city'. Attaching object clauses to attitude verbs such as 'know' or 'think' is an intensional construction: In the sentence 'Fred knows that the conman is from Wiesbaden', substituting the place name is not necessarily legitimate because Fred might have wrong ideas (or no idea at all) about Hessen's capital city. According to Zimmermann, this distinction between extensional and intensional constructions is pivotal: Whilst the first type of construction can be captured by simple set-theoretic means, the second type demands much more sophisticated methods of information processing.
Intensional constructions typically involve (complete or incomplete) sentences, as in the case of object clause attachment mentioned above. According to a highly influential tradition, this is no coincidence: According to propositionalist analyses, intensionality is always a result of clausal embedding, to which apparent counterexamples can be attributed through suitable paraphrases.
In fact, in formal semantics, such constructions are often treated as underlying clausal embedding. The propositionalism project now underway in Frankfurt devotes itself to the general question of the extent to which the propositionalist strategy can be applied to any kind of intensional construction in arbitrary languages.
The project is not, however, confined to detecting and analysing potential counterexamples. According to Zimmermann, the risk – which is a typical characteristic of Koselleck projects – lurks above all in theory development, since previous attempts in this direction have shown that by the use of algebraic coding methods apparent counterexamples can be reformulated in such a way that they fulfil the propositionalist hypothesis at least in letter. What is needed in order to get to the bottom of this is interdisciplinary expertise in the areas of linguistics, logic, and philosophy of language, which the project manager and his (initially) four assistants as well as a whole number of international collaborators are able to contribute.
The Koselleck project is already the fifth at Goethe University Frankfurt. According to the German Research Foundation, the funding programme, which was launched in 2008, "enables outstanding researchers with a proven scientific track record to pursue exceptionally innovative, higher-risk projects". The programme is named after Reinhart Koselleck who died in 2006. He was one of the most prominent historians of the 20th century and a founder of modern social history in Germany.
Thomas Ede Zimmermann