It is widely believed that for all p, or at least for all entertainable p, it is knowable a priori that (p iff actually p). It is even more widely believed that for all such p, it is knowable that (p iff actually p). There is a simple argument against these claims from four antecedently plausible premises.

Current orthodoxy in modal logic and metaphysics has it that actuality is non-contingent in the following sense: for all p, if actually, p, then necessarily, actually, p. Call this thesis (Actuality) Necessitism and its negation (Actuality) Contingentism. Thus, according to Contingentism, there is at least one proposition p which is actually true but which could have been actually false. In another paper, one of us (Glazier 2023) has recently defended Contingentism. The present paper explores the logic of actuality under Contingentism. (...) After informally introducing Contingentism and outlining what we take to be the main motivations for accepting it, we consider how contingent actuality should be taken to be. We argue that the nature, or essence, of actuality imposes certain limits on the extent to which actuality could have been different, and these then inform our view of the logic of actuality. Turning to the formal study of the logic of contingent actuality, we specify a formal language and a possible world semantics for that language and distinguish a number of natural notions of validity and consequence to which it gives rise. We present axiomatizations of the different resulting logics and examine the variety of iterated modalities in our systems. We establish soundness and completeness results. (shrink)

Some philosophers, like Kripke, Williamson, Hawthorne, and Turri, have offered examples of claims that are allegedly contingent and a priori justifiable. If any of these examples is genuine, this would upend the traditional epistemological classification on which (a) all and only a priori justifiable claims are necessary and (b) all and only a posteriori ones are contingent. I argue here that these examples are not genuine. This conclusion is not new, but the strategy pursued here is to formalize these muchdiscussed (...) examples in symbolic logics. Once formalized, a perspicuous representation of their logical form will bring into sharp relief that these examples are not both contingent and a priori. Two takeaways are (1) that the traditional epistemological classification remains plausible and (2) that one’s proposed examples of contingent a priori claims should be supported by a formalization in one’s preferred background symbolic logic. (shrink)

In his 2022 article ‘A puzzle about the fixity of the past’, Lampert argues that standard views concerning knowledge and the semantics of ‘actually’ conflict with a widely held principle concerning the fixity of the past. I show that his attempt to establish the conflict fails, as it rests on the implicit assumption that a past mental state or utterance involving a modal indexical must have the same content across worlds with a shared past, when in fact it must, given (...) its character, differ in content. (shrink)

Theories of propositions as sets of truth-supporting circumstances are committed to the thesis that sentences or other representations true in all and only the same circumstances express the same proposition. Theories of propositions as complex, structured entities are not committed to this thesis. As a result, structured propositions can play a role in our theories of language and thought that sets of truth-supporting circumstances cannot play. To illustrate this difference, I sketch a theory of transparent, non-deflationary truth consistent with some (...) theories of structured propositions, but inconsistent with any theory of propositions as sets of truth-supporting circumstances. (shrink)

A singular thought about an object o is one that is directly about o in a characteristic way—grasp of that thought requires having some special epistemic relation to the object o, and the thought is ontologically dependent on o. One account of the nature of singular thought exploits a Russellian Structured Account of Propositions, according to which contents are represented by means of structured n-tuples of objects, properties, and functions. A proposition is singular, according to this framework, if and only (...) if it contains an object as a constituent. One advantage of the framework of Russellian Structured propositions is that it promises to provide a metaphysical basis for the notion of a singular thought about an object, grounding it in terms of constituency. In this paper, we argue that the attempt to ground the peculiar features of singular thoughts in terms of metaphysical constituency fails, and draw some consequences of our discussion for other debates. (shrink)

The common wisdom, among philosophers of language and metaphysicians of analytic tradition, is that though only actual things exist, ‘being actual’ and its cognates do not ascribe a special feature...

The paper is an investigation into the concept of actuality from the standpoint of the philosophy of language. It is argued that expressions such as 'actually' and 'in fact' are not indexicals like 'here' and 'now'; when e.g. 'Snow is actually white' is uttered in a world, what proposition is conveyed does not depend on the world. Nor are such expressions ambiguous. The paper makes a suggestion about the role that 'actually' and its cognates do play. It is also argued (...) that the sentence ⌜Actually S ⌝ expresses a necessary truth only if S itself expresses one. In order to capture the necessitation of the proposition expressed in ⌜Actually S ⌝, it is not sufficient to prefix the word 'necessarily'. (shrink)