Online research in philosophy

With each proposition P we associate a set of proposition (a hyperproposition) which determines the order in which one may retreat from accepting P, if one cannot fully hold on to P. We first describe the structure of hyperpropositions. Then we describe two operations on propositions, subtraction and merge, which can be modelled in terms of hyperpropositions. Subtraction is an operation that takes away part of the content of a proposition. Merge is an operation that determines the maximal consistent content of two propositions considered jointly. The merge operation gives rise to an inference relation which is, in a certain sense, optimally paraconsistent.

John Stuart Mill (1843) thought that proper names denote individuals and do not connote attributes. Contemporary Millians agree, in spirit. We hold that the semantic content of a proper name is simply its referent. We also think that the semantic content of a declarative sentence is a Russellian structured proposition whose constituents are the semantic contents of the sentence’s constituents. This proposition is what the sentence semantically expresses. Therefore, we think that sentences containing proper names semantically express singular propositions, which are propositions having individuals as constituents. For instance, the sentence ‘George W. Bush is human’ semantically expresses a proposition that has Bush himself as a constituent. Call this theory Millianism. Many philosophers initially find Millianism quite appealing, but find it much less so after considering its many apparent problems. Among these problems are those raised by non-referring names, which are sometimes (tendentiously) called empty names. Plausible examples of empty names include certain names from fiction, such as ‘Sherlock Holmes’, which I shall call fictional names, and certain names from myth and false scientific theory, such as ‘Pegasus’ and ‘Vulcan’, which I shall call mythical names. I have defended Millianism from objections concerning empty names in previous work (Braun 1993). In this paper, I shall re-present those objections, along with some new ones. I shall then describe my previous Millian theory of empty names, and my previous replies to the objections, and consider whether the theory or replies need revision. I shall next consider whether fictional and mythical names are really empty. I shall argue that at least some utterances of mythical names are.

It is argued that taken together, two widely held claims ((i) sentences express structured propositions whose structures are functions of the structures of sentences expressing them; and (ii) senteces have underlying structures that are the input to semantic interpretation) suggest a simple, plausible theory of propositional structure. According to this theory, the structures of propositions are the same as the structures of the syntactic inputs to semantics they are expressed by. The theory is defended against a variety of objections.

Our purpose is to formulate a complete logic of propositions that takes into account the fact that propositions are both senses provided with truth values and contents of conceptual thoughts. In our formalization, propositions are more complex entities than simple functions from possible worlds into truth values. They have a structure of constituents (a content) in addition to truth conditions. The formalization is adequate for the purposes of the logic of speech acts. It imposes a stronger criterion of propositional identity than strict equivalence. Two propositions P and Q are identical if and only if, for any illocutionary force F, it is not possible to perform with success a speech act of the form F(P) without also performing with success a speech act of the form F(Q). Unlike hyperintensional logic, our logic of propositions is compatible with the classical Boolean laws of propositional identity such as the symmetry and the associativity of conjunction and the reduction of double negation.

According to many actualists, propositions, singular propositions in particular, are structurally complex, that is, roughly, (i) they have, in some sense, an internal structure that corresponds rather directly to the syntactic structure of the sentences that express them, and (ii) the metaphysical components, or constituents, of that structure are the semantic values — the meanings — of the corresponding syntactic components of those sentences. Given that reference is "direct", i.e., that the meaning of a name is its denotation, an apparent consequence of this view is that any proposition expressed by a sentence containing a name that denotes a contingent being S is itself contingent — notably, the proposition [S does not exist]. Assuming that an entity must exist to have a property, necessarily, [S does not exist] must exist in order to be true. It seems to follow that, necessarily, [S does not exist] is not true and, hence, that S is not contingent after all. Past approaches to the problem — notably, those of Prior and Adams — lead to highly undesirable consequences for quantified modal logic. In this paper, several solutions to this puzzle are developed that preserve actualism, the structured view of propositions, the direct theory of reference, and the intuition that [S does not exist] is indeed possible without the adverse consequences for QML of previous solutions.

The problem of the ‘Unity of the Proposition’ is the problem of explaining the difference between a content-expressing declarative sentence and a ‘mere list’ of referents. The prevailing view is that such a problem is to be solved metaphysically, either by reducing our ontology to exclude propositions or universals, or by explaining how it is possible for a certain kind of complex entity – the ‘proposition’– to ‘unify’ its constituents. I argue that these metaphysical approaches cannot succeed; instead the only viable approach is linguistic, identifying features of the (type–) sentence itself that enable it to express a content. Thus the problem of the ‘Unity of the Proposition’ (distinguishing sentences from lists) is distinct from the problem of ‘propositional unity’ (explaining how the constituents of propositions form a unified content). I suggest that, while the latter problem is not pressing, the former does not permit of an answer which applies in generality in all languages; we can only fully explain the Unity of the Proposition for single languages or groups of similar languages.

In Bertrand Russell’s The Principles of Mathematics and related works, the notion of a proposition plays an important role; it is by analyzing propositions, showing what kinds of constituents they have, that Russell arrives at his core logical concepts. At this time, his conception of proposition contains both a conventional and an unconventional part. The former is the view that propositions are the ultimate truth-bearers; the latter is the view that the constituents of propositions are “worldly” entities. In the latter respect, Russellian propositions are akin to states-of-affairs on some robust understanding of these entities. The idea of Russellian propositions is well known, at least in outline. Not so well known is his treatment of truth, which nevertheless grows directly out of this notion of proposition. For the early Russell, the import of truth is primarily metaphysical, rather than semantic; reversing the usual direction of explanation, he holds that truth is explanatory of what is the case rather than vice versa. That is, what properties a thing has and what relations it bears to other things is determined, metaphysically speaking, by there being a suitable array of true and false propositions. In the present paper, this doctrine is examined for its content and motivation. To show that it plays a genuine role in Russell’s early metaphysics and logic, I examine its consequences for (1) the possibility of truth-definitions and (2) the problem of the unity of the proposition. I shall draw a few somewhat tentative conclusions about where Russell stood vis-à-vis his metaphysics of propositions, suggesting a possible source of dissatisfaction that may have played a role in his eventual rejection of his early notion of proposition.

Propositions are the referents of the ‘that’-clauses that appear in the direct object positions of typical ascriptions of assertion, belief, and other binary cognitive relations. In that sense, propositions are the objects of those cognitive relations. Propositions are also the semantic contents (meanings, in one sense ) of declarative sentences, with respect to contexts. They are what sentences semantically express, with respect to contexts. Propositions also bear truth-values. The truth-value of a sentence, in a context, is the truth-value of the proposition that it semantically expresses, in that context. This much is common ground among many (but not all) philosophers. I accept other claims about propositions that are more controversial. Propositions (I hold) are Russellian: they are structured entities whose constituents include individuals, properties, and relations. The contribution of a proper name to the proposition that a sentence semantically expresses (in a context) is the referent of that name. Thus, the semantic content of ‘Bill Clinton’ is Bill Clinton himself, and the semantic content of ‘Bill Clinton smokes’ is a proposition whose constituents are Bill Clinton and the property of smoking (ignoring tense, as I shall do from here on). Such 1 singular propositions are among the objects of belief, assertion, and other cognitive relations. This combination of a Millian view about proper names with a Russellian theory of propositions might appropriately be called ‘Millian Russellianism’, or ‘MR’ for short. David Chalmers, in his stimulating paper “Probability and Propositions,” defines a closely related view, Referentialism, as follows (see also the penultimate paragraph of his introduction). Referentialist views say that insofar as beliefs are about individuals (such as Nietzche), the objects of these belief are determined by those individuals. On one such view, the objects of belief are Russellian propositions composed from the individuals and properties that one’s belief is about..

I argue that the best way to solve Russell's problem of the relationship between propositions and their constituents is to think of propositions as properties of worlds. I argue that this view preserves the strengths and avoids some of the weaknesses of the view of the metaphysics of propositions defended by Jeff King in his _The Nature and Structure of Content_, and that it provides an explanation of the representational properties of propositions and the nature of indexical belief. I conclude by discussing some problems about how to think about the semantics of propositional attitude ascriptions, if a view of this sort is correct.

Belief in propositions no longer brings about the sorts of looks it did when Quine's affinity for desert landscapes held sway in the Anglo-American philosophical scene. People are doing work in the metaphysics of propositions, trying to figure out what sorts of creatures propositions are. In philosophers like Frege, Russell, and Moore we have strong shoulders upon which to stand. But, there is much more work that needs to be done. I will try to do a bit of that work here. In the paper, I will probe the notion that propositions are structured entities, and that it is useful to think of their structure as resembling the structure of the sentences which express them. First, I will speak briefly to the issue of why one might find it rational to believe that propositions exist. In the second part of the paper, I will argue that we should think of propositions as having structure. In the last section, I will examine the nature of the structure of propositions. I will consider a recent account given by Jeffrey King of the nature of the relation that unifies constituents. I conclude by sketching my own view of the relation that holds between propositional constituents in virtue of which they compose a proposition. 1 I Why Believe in Propositions? Propositions are taken to be abstract entities that are a) the primary bearers of truth and falsity, b) the objects of our propositional attitudes, and c) the referents of "that-.