A selective annotated bibliography of recent literature on a priori knowledge.

According to Essentialism, an object’s properties divide into those that are essential and those that are accidental. While being human is commonly thought to be essential to Socrates, being a philosopher plausibly is not. We can motivate the distinction by appealing—as we just did—to examples. However, it is not obvious how best to characterize the notion of essential property, nor is it easy to give conclusive arguments for the essentiality of a given property. In this paper, I elaborate on these (...) issues and explore the way in which essential properties behave in relation to other related properties, like sufficient-for-existence properties and individual essences. (shrink)

Identity theories are those that hold that 'sensations are brain processes'. In particular, they hold that mental/psychological state kinds are identical to brain/neuroscientific state kinds. In this paper, I isolate and explain some of the key features of contemporary identity theories. They are then contrasted with the main live alternatives by means of considering the two most important lines of objection to identity theories.

I present and clarify one form of the modal argument for substance dualism, and go on to state and provide defeaters for five of the major arguments raised against the modal argument as a whole. I do not provide an unabridged defence of the modal argument. Instead, I focus on a range of defeaters scattered throughout the literature that are raised against the modal argument. In my view, these have not been gathered in one place and freshly evaluated. Accordingly, my (...) limited purpose is to fill this lacuna. Thus, I present a representative version of the modal argument to set the context for what follows. Next, I clarify and critique the five major objections directed at the modal argument in general. (shrink)

I focus on a key argument for global external world scepticism resting on the underdetermination thesis: the argument according to which we cannot know any proposition about our physical environment because sense evidence for it equally justifies some sceptical alternative (e.g. the Cartesian demon conjecture). I contend that the underdetermination argument can go through only if the controversial thesis that conceivability is per se a source of evidence for metaphysical possibility is true. I also suggest a reason to doubt that (...) conceivability is per se a source of evidence for metaphysical possibility, and thus to doubt the underdetermination argument. (shrink)

Many philosophers since Hume have accepted that imagining/conceiving a scenario is our prime guide to knowing its possibility. Stephen Yablo provided a more systematic criterion: one is justified in judging that p is possible if one can imagine a world which one takes to verify p. I defend a version of Yablo’s criterion against van Inwagen’s moderate modal scepticism. Van Inwagen’s key argument is that we cannot satisfy Yablo’s criterion because we are not in a position to spell out far-fetched (...) possible scenarios in relevant detail. Van Inwagen’s argument can be applied to the use of conceivability for everyday possibility claims, leaving us with the spectre of pervasive modal scepticism. In order to answer the sceptical threat, I combine van Inwagen’s main example with general considerations about the nature of metaphysical modality to motivate a version of Yablo’s criterion and show that it does not lead to scepticism. One structural condition of p being metaphysically possible is that it coheres with a complete reality. This condition gives rise to Yablo’s criterion. However, for the criterion to be of any avail, we have to disregard details we are not in a position to specify. To account for our practice of doing so, I use Yablo’s distinction between imagining a world as determinate and imagining it determinately. I present a condition when we may simply disregard details as determinate. The condition results from integrating analogical reasoning into the conceivability test. (shrink)

The negative zombie argument concludes that physicalism is false from the premises that p ∧¬q is ideally negatively conceivable and that what is ideally negatively conceivable is possible, where p is the conjunction of the fundamental physical truths and laws and q is a phenomenal truth (Chalmers 2002; 2010). A sentence φ is ideally negatively conceivable iff φ is not ruled out a priori on ideal rational reflection. In this paper, I argue that the negative zombie argument is neither a (...) priori nor conclusive. First, I argue that the premises of the argument are true only if there exists an adequate finite ideal reasoner R that believes ◊(p ∧ ¬q) on the basis of not believing p→q on a priori basis. Roughly, a finite reasoner is a reasoner with cognitive limitations (e.g. finite memory). I argue that R is finite only if R reasons nonmonotonically and only approach ideal reflection at the limit of a reasoning sequence. This would render the argument nonconclusive. Finally, I argue that, for some q, R does not believe ◊(p ∧ ¬q) on the basis of not believing p→q on a priori basis (e.g. for q =‘something is conscious’). This would render the choice of an adequate q dependent on empirical information (and the argument a posteriori). I conclude that the negative zombie argument (and, maybe, all zombie arguments) is neither a priori nor conclusive. (shrink)

Haecceitism and Hume’s Dictum are each controversial theses about necessity and possibility. According to haecceitism, there are qualitatively indiscernible possible worlds that differ only with respect to which individuals occupy which qualitative roles. According to Hume’s Dictum, there are no necessary connections between distinct entities or, as Humeans sometimes put it, reality admits of “free recombination” so any entities can co-exist or fail to co-exist. This paper introduces a puzzle that results from the combination of haecceitism and Hume’s Dictum. This (...) puzzle revolves around the free recombination of non-qualitative properties like being Socrates. After considering several responses to this puzzle, I defend an ideology-driven solution, which dispenses with non-qualitative properties like being Socrates in favour of primitive theoretical ideology while, at the same time, preserving a commitment to both haecceitism and Hume’s Dictum. (shrink)

In this paper, after clarifying certain features of Gideon Rosen’s Modal Fictionalism, I raise two problems for that view and argue that these problems strongly suggest that advocates of a “Deflationist Strategy” ought not to endorse, or adopt Rosen-style Modal Fictionalism.

The dissertation is in the format of a collection of several academic texts, composed of a two-part presentation and three papers on the topic of conceivability and the epistemology of modality. The presentation is composed of, first, a general introduction to conceivability theses and objections and, second, a discussion of two cases. Following the presentation, Asger provides three papers. The first paper, Pretense and Conceivability: A reply to Roca-Royes, presents a problem and a dilemma for Roca-Royes’ Non-Standard Dilemma for conceivability-based (...) epistemologies of de re modality in which she concludes that conceivability cannot be the whole story of our de re modal knowledge. The second paper, Conceivability Externalized, proposes an externalist conceivability-based epistemology of possibility inspired by Stalnaker. The third paper, Inconceivability as a Guide to Impossibility, considers inconceivability as an epistemic guide to impossibility, aiming to explore and add support to the underexplored thesis that one can justify beliefs about the impossibility of P on the basis of the inconceivability of P. (shrink)

The notion of an ideal reasoner has several uses in epistemology. Often, ideal reasoners are used as a parameter of (maximum) rationality for finite reasoners (e.g. humans). However, the notion of an ideal reasoner is normally construed in such a high degree of idealization (e.g. infinite/unbounded memory) that this use is unadvised. In this dissertation, I investigate the conditions under which an ideal reasoner may be used as a parameter of rationality for finite reasoners. In addition, I present and justify (...) the research program of computational epistemology, which investigates the parameter of maximum rationality for finite reasoners using computer simulations. (shrink)

Accounts of modal knowledge are many and varied. How should we choose between them? I propose that we employ inference to the best explanation, and I suggest that there are three desiderata that we should use to rank hypotheses: conservatism, simplicity, and the ability to handle disagreement. After examining these desiderata, I contend that they can’t be used to justify belief in the modal epistemology that fares best, but that they can justify our accepting it in an epistemically significant sense. (...) Finally, I outline a modal epistemology that seems to do well by the standards I’ve recommended. (shrink)