Juan Comesaña

No False Lemmas (NFL) says: necessarily, S’s belief that p is knowledge only if it is not inferred from any falsehood. Its proponents argue that alleged counterexamples to NFL are really cases of knowledge despite falsehood, wherein the false premise is inessential to the inference; perhaps some nearby truth does the justificatory heavy-lifting. We argue that there can be cases of inferential knowledge from a blindspot premise. Given that in such cases the relevant falsehood is essential to the inference, one cannot employ the knowledge despite falsehood strategy to defend NFL. We conclude by discussing how cases of knowledge from blindspots exemplify one way in which we can gain inferential knowledge defectively or non-ideally.

In Being Rational and Being Right, Juan Comesaña argues for a cluster of theses related to the rationality of action and belief. His starting point is that rational action requires rational belief but tolerates false belief. From there, Comesaña provides a novel account of empirical evidence according to which said evidence consists of the content of undefeated experiences. This view, which Comesaña calls "Experientialism," differs from the two main views of empirical evidence on offer nowadays: Factualism, according to which our evidence is what we know, and Psychologism, according to which our experiences themselves are evidence. He reasons that Experientialism fares better than these rival views in explaining different features of rational belief and action. Comesaña embeds this discussion in a Bayesian framework, and discusses in addition the problem of normative requirements, the easy knowledge problem, and how Experientialism compares to Evidentialism, Reliabilism, and Comesaña's own (now superseded) Evidentialist Reliabilism.

In this paper I argue against Mentalism, the claim that all the factors that contribute to the epistemic justification of a doxastic attitude towards a proposition by a subject S are mental states of S. My objection to mentalism is that there is a special kind of fact (what I call a "support fact") that contributes to the justification of any belief, and that is not mental. My argument against mentalism, then, is the following: Anti-mentalism argument: 1. If mentalism is true, then support facts are mental. 2. Support facts are not mental. Therefore, 3. Mentalism is not true. In what follows I explain what support facts are, and then defend each of the premises of my argument. I conclude with some remarks regarding the relevance of my argument for the larger internalism/externalism debate(s) in epistemology.

In this paper I argue that McDowell's brand of disjunctivism about perceptual knowledge is ill‐motivated. First, I present a reconstruction of one main motivation for disjunctivism, in the form of an argument that theories that posit a “highest common factor” between veridical and non‐veridical experiences must be wrong. Then I show that the argument owes its plausibility to a failure to distinguish between justification and warrant (where “warrant” is understood as whatever has to be added to true belief to yield knowledge).

The traditional view in epistemology is that we must distinguish between being rational and being right (that is also, by the way, the traditional view about practical rationality). In his paper in this volume, Williamson proposes an alternative view according to which only beliefs that amount to knowledge are rational (and, thus, no false belief is rational). It is healthy to challenge tradition, in philosophy as much as elsewhere. But, in this instance, we think that tradition has it right. In this paper we defend our version of the traditional view and argue against Williamson’s alternative.

Evidentialism and Reliabilism are two of the main contemporary theories of epistemic justification. Some authors have thought that the theories are not incompatible with each other, and that a hybrid theory which incorporates elements of both should be taken into account. More recently, other authors have argued that the resulting theory is well- placed to deal with fine-grained doxastic attitudes (credences). In this paper I review the reasons for adopting this kind of hybrid theory, paying attention to the case of credences and the notion of probability involved in their treatment. I argue that the notion of probability in question can only be an epistemic (or evidential) kind of probability. I conclude that the resulting theory will be incompatible with Reliabilism in one important respect: it cannot deliver on the reductivist promise of Reliabilism. I also argue that attention to the justification of basic beliefs reveals limitations in the Evidentialist framework as well. The theory that results from the right combination of Evidentialism and Reliabilism, therefore, is neither Evidentialist nor Reliabilist.

This dissertation is about rationality, both practical rationality , and theoretical rationality . I argue that there are interesting similarities as well as interesting differences between practical and theoretical rationality. One of the similarities is that both of them are essentially related to the explanation of actions and beliefs, and one of the differences is that whereas theoretical rationality has the hyper-external aim of truth, practical rationality has the non-hyper-external aim of desire satisfaction. ;In chapter 1 I present a general framework for the development of theories of rationality, and in chapter 2 I apply that framework to practical rationality. The result is an instrumentalist view of practical rationality. In chapter 3 I discuss the relation between practical rationality and morality, and I argue that one can be an instrumentalist about practical rationality without being a subjectivist about morality, even while accepting plausible forms of motivational internalism. In chapter 4 I argue that theoretical rationality is not reducible to practical rationality. In chapter 5 I apply the framework of chapter I to theoretical rationality, and the result is a theory with both internalist and externalist components. In chapters 6 through 8 I defend that theory from some of the main objections that can be leveled at it, such as the objection from disjunctivism and the "new evil demon problem"

Reliabilism about epistemic justification - the thesis that what makes a belief epistemically justified is that it was produced by a reliable process of belief-formation - must face two problems. First, what has been called "the new evil demon problem", which arises from the idea that the beliefs of victims of an evil demon are as justified as our own beliefs, although they are not - the objector claims - reliably produced. And second, the problem of diagnosing why skepticism is so appealing despite being false. I present a special version of reliabilism, "indexical reliabilism", based on two-dimensional semantics, and show how it can solve both problems.

The two main theories of perceptual reasons in contemporary epistemology can be called Phenomenalism and Factualism. According to Phenomenalism, perceptual reasons are facts about experiences conceived of as phenomenal states, i.e., states individuated by phenomenal character, by what it’s like to be in them. According to Factualism, perceptual reasons are instead facts about the external objects perceived. The main problem with Factualism is that it struggles with bad cases: cases where perceived objects are not what they appear or where there is no perceived object at all. The main problem with Phenomenalism is that it struggles with good cases: cases where everything is perfectly normal and the external object is correctly perceived, so that one’s perceptual beliefs are knowledge. In this paper we show that there is a theory of perceptual reasons that avoids the problems for Factualism and Phenomenalism. We call this view Propositionalism. We use ‘proposition’ broadly to mean the entities that are contents of beliefs and other doxastic attitudes. The key to finding a middle ground between Phenomenalism and Factualism, we claim, is to allow our reasons to be false in bad cases. Despite being false, they are about the external world, not our phenomenal states

We examine whether the "evidence of evidence is evidence" principle is true. We distinguish several different versions of the principle and evaluate recent attacks on some of those versions. We argue that, whatever the merits of those attacks, they leave the more important rendition of the principle untouched. That version is, however, also subject to new kinds of counterexamples. We end by suggesting how to formulate a better version of the principle that takes into account those new counterexamples.