Brian Leahy

Why do utterances of counterfactual conditionals typically, but not universally, convey the message that their antecedents are false? I demonstrate that two common theoretical commitments–commitment to the existence of scalar implicature and of informative presupposition—can be supplemented with an independently motivated theory of the presuppositions of competing conditional alternatives to jointly predict this information when and only when it appears. The view works best if indicative and counterfactual conditionals have a closely related semantics, so I conclude by undermining two familiar arguments for a nonunified semantics of indicative and counterfactual conditionals.

This paper responds to a problem, raised by Martinez, for Millikan’s explanation of the interpretability of novel signs in terms of mapping functions. I argue that Martinez’s critique is a logically weakened version of Kripke’s skeptical argument about rule following. Responding to Martinez requires two things. First, we must correctly understand the role of simplicity and elegance in choosing the correct mapping function for a signaling system. Second, we need to understand that mapping functions are descriptions of the features that determine the content of signs; they do not themselves determine the content of signs. Bearing these facts in mind, Martinez’s concern is assuaged. However, we find that this position on the role of mapping functions is not fully consistent with Millikan’s response to Kripke. I modify her response to Kripke and demonstrate that the alterations do not undermine her view.

We use mental files to present an analysis of children's developing understanding of identity in alternative naming tasks and belief. The core assumption is that younger children below the age of about 4 years create different files for an object depending on how the object is individuated. They can anchor them to the same object, hence think of the same object whether they think of it as a rabbit or as an animal. However, the claim is, they cannot yet link their files to one another to represent that they have the same referent. Without linking the information contained in one file is not available in the other file. Hence, when thinking of the object as a rabbit the information that it is also an animal is not available. For representing a person's belief about an object a vicarious file contains what the person believes about the object. To capture that the belief is about that object the vicarious file has to be linked to the regular file, which by assumption children younger than 4 years cannot do. This assumption can therefore explain why problems with alternative naming and understanding false beliefs are overcome at the same age.

Alvin Plantinga’s Evolutionary Argument Against Naturalism aims to show that the conjunction of contemporary evolutionary theory (E) with the claim that there is no God (N) cannot be rationally accepted. Where R is the claim that our cognitive faculties are reliable, the argument is: The probability of R given N and E is low or inscrutable.Anyone who sees (1) and accepts (N&E) has a defeater for R, and this defeater cannot be defeated or deflected.Anyone who has an undefeated, undeflected defeater for R has an undefeated, undeflected defeater for everything she believes.Therefore she has an undefeated, undeflected defeater for (N&E).Plantinga (2011) defends the second premise. It examines and rejects several candidate defeater defeaters and defeater deflectors. One candidate is Millikan’s teleosemantics. I show that Plantinga’s motives for rejecting teleosemantics as a defeater deflector are inadequate. I then show that teleosemantics is not on its own an adequate defeater deflector. Then I offer an additional premise that constitutes a defeater deflector in conjunction with teleosemantics

Scalar implicatures arise when a speaker uses a logically weak alternative in a context where a logically stronger alternative was available. Presuppositional implicatures, as I call them, arise when a speaker uses a presuppositionally weak alternative when a presuppositionally stronger alternative was available. My goal is to give a detailed, working theory of presuppositional implicatures, and show that they are a special case of scalar implicatures. In doing so, I carefully contrast presuppositional implicatures with antipresuppositions. These two phenomena have been treated as closely related in the literature, but some differences have not been adequately appreciated. Antipresuppositions are observed when a presuppositionally weak alternative is infelicitously used in a context that satisfies the presupposition of a presuppositionally stronger alternative. Presuppositional implicatures arise when a presuppositionally weak alternative is felicitously used in a context that does not satisfy the presupposition of a presuppositionally stronger alternative, but where that stronger presupposition would have been accommodated. Attention to this difference reveals a shortcoming in Schlenker’s theory of presuppositional implicature. This paper both identifies and remedies that shortcoming

Since the publication of Ruth Millikan's Language, Thought, and Other Biological Categories in 1984, a great deal of literature has discussed her so-called teleosemantic or biosemantic solution to the problem of intentionality. Only recently, though, has much attention been paid to her co-ordinated solution to the problem of productivity. This article, first, clearly describes the problems of intentionality, productivity, and compositionality, and describes their relationships and their relevance for the theory of meaning. It then describes Millikan's proposal with respect to the problem of intentionality and shows how this buys her a novel solution to the problem of productivity. The article closes by discussing some alternative teleosemantic theories and some issues that will contribute to deciding between them.

Children approach counterfactual questions about stories with a reasoning strategy that falls short of adults’ Counterfactual Reasoning (CFR). It was dubbed “Basic Conditional Reasoning” (BCR) in Rafetseder et al. (Child Dev 81(1):376–389, 2010). In this paper we provide a characterisation of the differences between BCR and CFR using a distinction between permanent and nonpermanent features of stories and Lewis/Stalnaker counterfactual logic. The critical difference pertains to how consistency between a story and a conditional antecedent incompatible with a nonpermanent feature of the story is achieved. Basic conditional reasoners simply drop all nonpermanent features of the story. Counterfactual reasoners preserve as much of the story as possible while accommodating the antecedent.

Abstract Utterances of counterfactual conditionals are typically attended by the information that their antecedents are false. But there is as yet no account of the source of this information that is both detailed and complete. This paper describes the problem of counterfactual antecedent falsity and argues that the problem can be addressed by appeal to an adequate account of the presuppositions of various competing conditional constructions. It argues that indicative conditionals presuppose that their antecedents are epistemically possible, while subjunctive conditionals bear no presupposition. Given this arrangement, utterance of the counterfactual results in an antipresupposition, that is, a scalar implicature generated from the presuppositions of competing alternatives rather than from the at-issue content of competing alternatives. The content of the antipresupposition is the negation of the presupposition of the competing indicative, i.e., that the antecedent of the conditional is known to be false by the speaker.

We provide a cognitive analysis of how children represent belief using mental files. We explain why children who pass the false belief test are not aware of the intensionality of belief. Fifty-one 3½- to 7-year old children were familiarized with a dual object, e.g., a ball that rattles and is described as a rattle. They observed how a puppet agent witnessed the ball being put into box 1. In the agent’s absence the ball was taken from box 1, the child was reminded of it being a rattle, and emphasising its being a rattle it was put back into box 1. Then the agent returned, the object was hidden in the experimenter’s hands and removed from box 1, described as a ‘‘rattle,” and transferred to box 2. Children who passed false belief had no problem saying where the puppet would look for the ball. However, in a different condition in which the agent was also shown that the ball was a rattle they erroneously said that the agent would look for the ball in box 1, ignoring the agent’s knowledge of the identity of rattle and ball. Their problems cease with their mastery of second-order beliefs. Problems also vanish when the ball is described not as a rattle but as a thing that rattles. We describe how our theory can account for these data as well as all other relevant data in the literature