Giorgio Lenta

A counterpossible is a counterfactual with an impossible antecedent. Matthias Jenny has argued that relative computability theory provides examples of false counterpossibles. If Jenny were right, it would be highly significant, since it would follow that the standard analysis of counterfactuals, according to which counterpossibles are all vacuously true, is incorrect. In this paper, we argue against the claim that computability theory provides examples of false counterpossibles. We distinguish two ways of reading the alleged false counterpossibles. Under the first reading, they are indeed false, but, as we will argue, they are not genuine counterpossibles. Under the second reading, they are genuine counterpossibles, but they are true. There is a way to interpret the alleged false counterpossibles as false, and there is a way to interpret them as counterpossibles, but under none of these two interpretations they are false counterpossibles.

We investigate how compositionality can be preserved when modeling semantic content within an impossible worlds framework based on linguistic ersatzism. After a critical assessment of an existing technique due to Francesco Berto and Mark Jago, we illustrate how to overcome its limitations. We introduce a general method for recovering compositionality across a broad range of alternative notions of content and synonymy, as induced by the syntactic characterizations of popular conceptivist logics. Finally, we discuss the advantages and limitations of the strategy, and conclude with some further critical remarks on linguistic ersatzism.

David Kaplan famously argued that mainstream semantics for modal logic, which identifies propositions with sets of possible worlds, is affected by a cardinality paradox. Takashi Yagisawa showed that a variant of the same paradox arises when standard possible worlds semantics is extended with impossible worlds to deliver a hyperintensional account of propositions. After introducing the problem, we discuss two general approaches to a possible solution: giving up on sets and giving up on worlds, either in the background semantic framework or in the corresponding conception of propositions. As a result, we conclude that abandoning worlds by embracing a truthmaker-based approach offers a promising way to account for hyperintensional propositions without facing the paradoxical outcome.

Understanding the logical behavior of propositional attitudes, i.e. the mental states that we entertain with propositions (such as knowledge, belief, supposition, imagination, etc.), requires careful consideration of what such attitudes are about: their topic. This is the core intuition of Francesco Berto’s work, a book that fits into one of the most interesting and rich debates of recent decades, ranging over a wide variety of disciplines: from formal semantics to epistemology and even cognitive psychology. But above all, Berto’s book makes a substantial contribution to what Daniel Nolan calls the hyperintensional revolution. In addition to being an original and ambitious proposal in the area of epistemic logic, the book can also be considered an excellent and in-depth introduction to many of the most interesting problems in the contemporary debate.

A wide variety of concepts are nowadays considered to be hyperintensional, and some of them do not seem to involve our representational attitudes. This led some philosophers to identify and defend a notion of worldly hyperintensionality: the idea that some hyperintensional phenomena derive from features of objective reality, independently of how we represent it. Against this view, Darragh Byrne and Naomi Thompson argue that the correct understanding of such phenomena must be conceptualist in nature, and claim that hyperintensionality always derives from features of representations. In the present work I defend the genuine distinction between worldly and representational hyperintensionality through a new framing of the issue: the comparison with worldly intensionality. I argue that locating the sources of hyperintensionality should not be affected by preferences towards any specific semantic framework, and reject Byrne and Thompson's argument against worldly hyperintensionality.