Periodic Reporting for period 3 - TRUST (Truth and Semantics)
Période du rapport: 2021-10-01 au 2023-03-31
In semantics one attempts to give a systematic account of the meaning of sentences in natural language. This is everything but a trivial affaire. In particular, so-called self-referential sentences offer a stumbling block for developing natural language semantics but have been largely ignored by semanticists. However, research on self-reference and self-referential sentences is abundant in philosophy and philosophical logic in form of research on the Liar paradox (This sentence is not true. True or False?) and related paradoxes. Indeed, a number of accounts for dealing with self-reference have been developed in those fields---mostly in the form of theories of truth that avoid the paradoxical consequences. Implementing theories of truth within the framework of natural language semantics therefor amounts to an important step towards a satisfactory handling of self-referential sentences within natural language semantics.
This implementation runs into major problems with respect to, e.g. the semantics for natural language conditionals, belief ascriptions and, more generally so-called hyperintensional semantics. The principal focus of the first period of the project was devoted to developing theories of truth for such semantics. In particular, studies on theories of truth in hyperintensional languages have been produced and are ongoing. Similarly, a semantics for truth in belief contexts has been produced and studies on combining natural language conditionals and theories of truth are ongoing. By the end of the project an even richer toolkit for combining theories of truth with various semantics for fragments of natural language will be available and amount to an important step towards a satisfactory handling of self-referential sentences within natural language semantics.
The research is of a highly abstract and foundational nature, so pointing toward any immediate importance for society, which goes beyond the scientific importance of the project for understanding key philosophical notions such as truth and belief, natural language semantics, and self-reference, is a difficult task. However, handling self-reference is also one of the major challenges and stumbling blocks of the research on artificial intelligence and, albeit in a very indirect way, our research may raise awareness and improve our understanding of the challenges to come.
This implementation runs into major problems with respect to, e.g. the semantics for natural language conditionals, belief ascriptions and, more generally so-called hyperintensional semantics. The principal focus of the first period of the project was devoted to developing theories of truth for such semantics. In particular, studies on theories of truth in hyperintensional languages have been produced and are ongoing. Similarly, a semantics for truth in belief contexts has been produced and studies on combining natural language conditionals and theories of truth are ongoing. By the end of the project an even richer toolkit for combining theories of truth with various semantics for fragments of natural language will be available and amount to an important step towards a satisfactory handling of self-referential sentences within natural language semantics.
The research is of a highly abstract and foundational nature, so pointing toward any immediate importance for society, which goes beyond the scientific importance of the project for understanding key philosophical notions such as truth and belief, natural language semantics, and self-reference, is a difficult task. However, handling self-reference is also one of the major challenges and stumbling blocks of the research on artificial intelligence and, albeit in a very indirect way, our research may raise awareness and improve our understanding of the challenges to come.
The project has two principal objectives corresponding to the two interrelated parts Truth in Semantics (Part A) and Truth and the Foundations of Semantics (Part B). The majority of the work conducted in the reporting period has been focused on Part A, that is, on developing semantics for object-linguistic truth in rich fragments of natural language. However, some important research has also been carried on Part B and, in particular, Subproject B1 and B2, and in particular the alleged ambiguity of the truth predicate and the relation of this thesis to contextualist account of truth. A variety of different research has been conducted since the beginning of the project some of which is still ongoing.
Concerning Part A the most important achievements to date are:
- Development of montone semantics for conditionals and generalized quantification.
- Development of theories of truth for hyperintensional semantics. In particular, Kripke's theory of has been applied to doxastic possible world semantics. This yields an intutively adequate semantics for truth an belief contexts that incorporates ideas from contextualist theories of attitude reports and awareness semantics.
Concerning Part A the most important achievements to date are:
- An in depth analysis of the natural language truth predicate has provided focusing on the questions of whether 'is true' is ambiguous, context-sensitive, vague or gradable?
- A conceptual study of whether the logical notion of truth and the semantic notion of truth can be reconciled, that is, a stufy of whether deflationism is compatible with Tarskian or compositional truth.
- An in depth study of a particular theory of truth, that is the theory Kripke-Feferman, which has led to a number of important technical results. The theory is arguably the best candidate truth theory for developing axiomatic semantics and the research clarifies the prospects and limitiations of such an endeavor.
Concerning Part A the most important achievements to date are:
- Development of montone semantics for conditionals and generalized quantification.
- Development of theories of truth for hyperintensional semantics. In particular, Kripke's theory of has been applied to doxastic possible world semantics. This yields an intutively adequate semantics for truth an belief contexts that incorporates ideas from contextualist theories of attitude reports and awareness semantics.
Concerning Part A the most important achievements to date are:
- An in depth analysis of the natural language truth predicate has provided focusing on the questions of whether 'is true' is ambiguous, context-sensitive, vague or gradable?
- A conceptual study of whether the logical notion of truth and the semantic notion of truth can be reconciled, that is, a stufy of whether deflationism is compatible with Tarskian or compositional truth.
- An in depth study of a particular theory of truth, that is the theory Kripke-Feferman, which has led to a number of important technical results. The theory is arguably the best candidate truth theory for developing axiomatic semantics and the research clarifies the prospects and limitiations of such an endeavor.
The main results obtained during the reporting period (mentioned above) yield genuinely new insights and showcase innovative research that goes beyond the state of the art. They address important research question that had not been in addressed in the literature to date. The development of semantics for object-linguistic truth in rich fragments of natural language is still ongoing (Part A). Until the end of the projecy the research on monotone semantics for conditionals and restricted quantifiers will be completed and the research on theories of truth in hyperintensional semantics will be completed by developing theories of truth for exact truthmaker semantics. Importantly further research on the foundations of truth-conditional semantics will be conducted until the end of the project. For one, a foundational view of truth-coditional semantics will be developed that attempts to justify and motivate the object/metalanguage distinction that underlies most contemporary linguistic practice. For another, an alternative foundational picture will be developed that dispenses of the object/metalanguage distinction but attemps to formulate semantics in a theory of self-appicable truth formulated over some suitable base theory.