Nick Leonard

Some prominent cognitive theories have adopted an intriguing idea from metaphysics: The conditions of identity and individuation of objects come from the meaning of sortal nouns—count nouns, such as “dog” or “cup.” According to this sortalist theory, Rover’s identity over time and his distinctness from Fido depend on the meaning of “dog.” This chapter first describes the sortalist view in metaphysics (section 11.1) and then traces the ways in which cognitive psychologists have adapted and modified this theory in an attempt to explain empirical data—people’s judgments about the nature of objects (section 11.2). Sections 11.3 and 11.4 then examine some recent work in philosophy and psychology, arguing that these findings raise two related, but distinct, worries for sortalism as a psychological theory (which is here called psychosortalism). Finally, section 11.5 assesses whether any of the original metaphysics can survive within the best cognitive theories of object concepts.

This paper is about an anti-expertise paradox that arises because of self-referential sentences like: = I do not believe that is true. The first aim is to motivate, develop, and defend a novel view of epistemic rationality according to which there can be genuine rational indeterminacy, i.e., it can be indeterminate which doxastic states an agent is rationally permitted or required to have. The second aim is to show how this view can provide a solution to this paradox while also avoiding the problems that plague its rivals.

This paper is about epistemic dilemmas, i.e., cases in which one is doomed to have a doxastic attitude that is rationally impermissible no matter what. My aim is to develop and defend a position according to which there can be genuine rational indeterminacy; that is, it can be indeterminate which principles of rationality one should satisfy and thus indeterminate which doxastic attitudes one is permitted or required to have. I am going to argue that this view can resolve epistemic dilemmas in a systematic way while also enjoying some important advantages over its rivals.

Sortal terms, such as table or horse, are count nouns (akin to a basic-level terms). According to some theories, the meaning of sortals provides conditions for telling objects apart (individuating objects, e.g., telling one table from a second) and for identifying objects over time (e.g., determining that a particular horse at one time is the same horse at another). A number of psychologists have proposed that sortal concepts likewise provide psychologically real conditions for individuating and identifying things. However, this paper reports five experiments that cast doubt on these psychological claims. Experiments 1-3 suggest that sortal concepts do not determine when an object ceases to exist and therefore do not decide when the object can no longer be identical to a later one. Experiments 4-5 similarly suggest that sortal concepts do not provide determinate conditions for individuating objects. For example, they do not always decide whether a room contains one table or two. All five experiments feature ordinary objects undergoing ordinary changes.

According to the Interpersonal View of Testimony, testimonial justification is non-evidential in nature. I begin by arguing that the IVT has the following problem: If the IVT is true, then young children and people with autism cannot participate in testimonial exchanges; but young children and people with autism can participate in testimonial exchanges; thus, the IVT should be rejected on the grounds that it has over-cognized what it takes to give and receive testimony. Afterwards, I consider what I take to be the two best motivations for the IVT and argue that they both fail. The overarching lesson, then, is that the IVT is unmotivated and false; we should think of testimonial justification as being evidential in nature.