Epistemologists are interested in what makes beliefs well justified. Even before considering competing theories of epistemic justification, however, we should ask what sort of valuational structure we are trying to explain. If, as far as epistemic justification is concerned, beliefs are like bank accounts, then all beliefs are comparable: just as in any bank account there must be more, less, or as much money as in any other, one belief must be better, worse, or as good as any other. Contemporary epistemologists take for granted the assumption that beliefs are comparable in the same way that bank accounts are comparable: bank accounts have balances, sprinters have personal bests for the 100-meter dash, and beliefs have degrees of justifiedness. Alternatively, we could understand the justificatory status of a belief to be more like the expensiveness of a restaurant. Consider a concept of restaurant expensiveness on which the expensiveness of a restaurant is determined by the range of prices for meals at that restaurant. If meals at Restaurant A are 25 to 50 and meals at B are 10 to 20, then A is more expensive than B. Restaurant C, however (30 to 40), is neither more nor less expensive than A. Nor is it equally expensive, for there are restaurants that are more expensive than C that are not more expensive than A (like D, 45 to 50). Some evaluative concepts, like this concept of restaurant expensiveness, do not reduce values to single numbers. If epistemic justification is like this, then there may be pairs of beliefs such that neither is better justified than the other, but nor are they equally well justified. Such beliefs would be incomparable. While incomparability is familiar in the ethics literature, it has not previously been explored in epistemology. I discuss the implications of allowing for incomparability in epistemology, both for theories of epistemic justification and theories of knowledge.

What is moral epistemology? It is the attempt to construct a theory that explains whether and how moral beliefs are epistemically justified. This dissertation is an evaluation of this project. Should we develop a specialized, topic-specific epistemology that applies only to the domain of morality, or should we develop a perfectly general theory which can be applied to ethics as a special case? In chapter one, I argue that we should be very cautious about developing topic-specific epistemologies like moral epistemology, and that we are in need of a good reason to do so. I explore and ultimately reject several skeptical motivations for the pursuit of moral epistemology. In chapter two, I sketch an argument put forth by Sinnott-Armstrong that because there are strong limits on the degree to which we can convince those who doubt the truth of our ethical beliefs, therefore a weak form of skepticism is reasonable. This argument fails because it targets nothing distinctive about morality. In chapter three, I consider Harman's view that there is something about our best epistemology that forces us to deny the existence of ethical facts. I reject this argument because the presupposed epistemology risks collapsing into general skepticism. In chapter four, I develop a new argument for moral skepticism. Sometimes if a person has the justified belief that there is enough disagreement about a topic this belief can defeat the justifications for that person's own beliefs about that topic. Given apparent widespread ethical disagreement, this presents a difficult challenge. In chapter five, I attempt to defuse the epistemological problem generated by disagreement, arguing that it is reasonable to deny that there is enough moral disagreement for the argument developed in chapter four to apply. Finally, in chapter six I consider a non-skeptical motivation for the development of moral epistemology, namely that there might be a process of belief formation important to moral beliefs but not to other sorts of beliefs. I argue that the moral emotions seem to carry some epistemic force, and that better understanding the moral emotions does provide an incentive for further work on moral epistemology.

When we believe for reasons, we appreciate those reasons. That is, we believe on the basis of those reasons. This relation between beliefs and their reasons is the basing relation. The basing relation is a psychological relation. How should we understand the nature of this relation? I examine two accounts: a causal theory of the basing relation and a noncausal, dispositional theory. Sententialism is the most widely embraced version of the causal theory of the basing relation. According to general sententialism, when beliefs are produced by deliberation, they are supported by a relation of causal production. Standing beliefs, on the other hand--our background beliefs--are organized into a structure of relations of causal sustaining. The systems theory provides a noncausal, dispositional account of the basing relation. A single, cognitively efficacious state contains all the contents we attribute when we attribute standing or "background" beliefs. These contents do not participate in relations of causal sustaining with each other. Nevertheless, we can make sense of the claim that some contents are based on others as reasons. The basing relation is understood in terms of counterfactual dependencies; or more generally, it is understood as a dispositional property. Counterfactual dependencies do not necessarily reflect the presence of causal relations. They may instead reflect our conceptual tools for organizing certain kinds of possibilities--possible ways that our public and cognitive behaviors might be. In the end, I argue for a "mixed" theory. If we claim that sententialism is true across the board, we encounter a serious objection: the problem of congestion. But if we claim that the systems theory is a theory of all intentional properties, we will be hard-pressed to say how the systems theory explains inferential activity and occurrent belief. The best solution is to admit that in the case of occurrent thought, sententialism is the best theory of belief states and the relations between them; while the systems theory accounts nicely for nonoccurrent thought and the basing relation between nonoccurrent contents. The basing relation is both causal and noncausal; it depends on what sort of beliefs you are interested in.

In this dissertation, I argue that the structure of eudaimonist ethics is similar to the structure of Kant's ethics and its relatives. In Chapter One, I discuss some different ways of thinking about the good life of a person and its relation to morality, as a way of situating eudaimonism and clarifying what is distinctive about it. In Chapter Two I argue that eudaimonism does not violate strong intuitions about the subjective aspect of the good life. In Chapter Three I discuss and defend the view of our nature to which Aristotle and other eudaimonists are committed. I argue reflection on our practical thinking reveals incompatibilities between the presuppositions we make in the practical sphere and a reductive naturalism. The Interlude explicates eudaimonia's conceptual role in the structure of human willing and the formal constraints of completeness and self-sufficiency . In Chapter Four, I argue that a dominant end interpretation of eudaimonism is motivated by an untenable consequentialist interpretation of our reasons for acting. In Chapter Five I develop a formal conception of eudaimonism, based on central features of our practical thought, or willing. The two key steps here are recognizing the essential intersubjective appeal at work in our willing, and recognizing the nature of this appeal. In Chapter Six I show how this formal conception can respond to a common objection to eudaimonist theory, that it presents an unacceptably egoistic account of our reasons for being moral.

Eudaimonism once had great success in fostering a public appreciation of philosophy. In contrast, a recent editorial on the subject of bioethics was titled, "The Ethicist's New Clothes." Contemporary ethical theories have not been well popularized, and to the public these theories seem untried. But perhaps the public is right to be suspicious of ethical accounts that regard ethics as the province of those with advanced training in philosophy. Once we start thinking this, we have perhaps forgotten what ethics is meant to do, and how it is meant to do what it does for all of us. In this project, I set up a contest between ethical theories, seeking to determine which is the most practically guiding to agents. In chapters one and two I argue that a number of contemporary approaches to ethics are inappropriately inapplicable. In contrast, a version of virtue ethics, ancient eudaimonist theory, is shown to be more applicable and practical to agents than either Kant's theory or consequentialism. In chapters three and four I argue for how this is. In chapters five and six, I look to how far-ranging ethical theories' applicability may be, by considering how eudaimonist ethical theory can help to justify political organization. Stoic and Epicurean eudaimonism, for example, can justify arrangements that we might recognize as liberal, but not by attempting to remain neutral on the subject of value.

There is something it is like to see a bright red cardinal, to touch a stucco wall, or to hear an ambulance pass by. Each of these experiences has a distinctive phenomenal character. But in virtue of what it is like to have a particular experience--in virtue of the experience's phenomenal character--the world is presented to the subject as being a certain way. The dissertation is concerned with the nature of this "phenomenal content". In Chapter One I argue that there is such a thing as phenomenal content, understood as intentional content that supervenes necessarily on phenomenal character. The rest of the dissertation is concerned with the nature of this phenomenal content, and in particular the phenomenal content of visual experiences. In Chapter Two I present and critique the dominant view about phenomenal color content, what I call "standard Russellianism". According to standard Russellianism, the content of color experience consists solely in the representation of specific mind-independent physical color properties. I present an argument against such views based on the possibility of spectrum inversion without illusion. Further, I argue that such views fail to properly accommodate the phenomenon of color constancy. In Chapter Three, I address a different form of Russellian theory of phenomenal content advocated by Sydney Shoemaker. I present my own positive view of phenomenal color content in Chapter Four. There I argue that color content is a kind of Fregean content, involving modes of presentation of colors. In particular, I argue that phenomenal color content involves indexical, response-dependent, and holistic modes of presentation. Finally, in Chapter Five I turn to the spatial aspects of visual experience. I argue against Russellianism for spatial phenomenal content, based on the consideration of a kind of spatial Twin Earth thought experiment. In its place, I argue that spatial phenomenal content is also a kind of Fregean content.

In epistemology, justification is supposed to capture what makes a belief reasonable as opposed to merely true. However, imagine someone in a society where throwing bones to predict the future is completely accepted. Of course this is a terrible way to come to hold beliefs, but if she is being as responsible as she knows how, we want to call her beliefs reasonable or justified in one sense, but not another. In this dissertation, I argue that we should incorporate two separate senses of justification into epistemological theorizing. Many philosophers have discussed two-sense views, but they have contrasted exclusive senses (e.g., a belief is either internally or externally justified), or included one sense within the other (e.g., all objectively justified beliefs must be subjectively justified as well). I am making a novel proposal, distinguishing between two overlapping senses: internal and objective senses of justification. They are independent but not exclusive, so that beliefs can be justified in either way independently, but the conditions for being justified in one sense do not fall completely outside of the conditions f or being justified in the other sense. Basically, a person's belief can be reasonable when considered on the inside or it can be reasonable when considered from an objective, all-things considered point of view . In Chapter One, I survey the internalism/externalism literature, in order to find in it a motivation for finding two senses of justification. I argue that intuitions and differences in use pose a strong motivation for attempting a two-sense view. My second chapter is a methodological one, exploring ways to make linguistic and theoretical arguments for adopting a two-sense view. In Chapter Three, I discuss various ways to disambiguate justification. I argue that the most promising way to make the distinction is between the internal and objective senses. Chapter Five is an argument that the internal/objective distinction has more theoretical utility and explanatory power than either a univocal sense or than other distinctions. The final chapter is an exploration of the implications of the internal/objective two-sense view for the internalism/externalism debate, justification, knowledge, and epistemology as a whole.

We must change our beliefs, and change them in particular ways, in response to new information. But not all changes are created equal: some are rational changes, some not. The Problem of Epistemic Change is the problem of specifying the rational constraints on how the epistemic state of an agent ought to change in the face of new information. This dissertation is about the philosophical and logical investigation of rational belief change. I start by arguing that the familiar foundations---coherence distinction from static epistemology does not adequately carve up the logical space of theories of epistemic change. It is better to think of theories as being loosely ordered along a continuum from more to less foundational. The ordering, however, is "clumpy" in the sense that there are large regions in the ordering which remain unexplored. I then present and develop GDEC which is a new foundations model of belief revision that fills a gap in this ordering of theories of epistemic change. The key insight in GDEC is that belief that...is ambiguous between the attitudes of accept that...and expect that... GDEC respects the difference and how it matters for epistemic change. I show that GDEC is a genuine competitor to the AGM theory of belief revision in the sense that the two approaches are incompatible. The remainder of the dissertation is devoted to exploring the logical dynamics of GDEC and the models I develop here which extend it by applying them to a series of richer epistemic environments. I show how puzzles and paradoxes which confound other theories of belief revision are solved in a unified way by GDEC and its extensions. In particular, I give solutions to Moore's Paradox, Fuhrmann's Impossibility Theorem, the Reduction Problem of Epistemic Conditionals, and the Gardenfors Impossibility Theorem.

I show Means/end or "instrumental" models of practical rationality maintain that an agent is rational if she is taking efficient means to secure her most important ends. According to this view, an agent's goals are not themselves open to rational assessment. Only the efficiency of means to chosen ends is evaluated. These accounts raise an important question in contemporary debates about practical rationality: whether a complete theory of practical rationality must include a theory of value (a theory by which ends are evaluated to determine whether they are rational). After placing various means/end accounts in historical perspective and illustrating their contemporary significance, I defend a negative answer to the above question and thus embrace a form of instrumentalism. I show that certain arguments concerning the rationality of final ends are reducible to arguments about other matters pertaining to things being constituents of ends or means to final ends. Moreover, examples of irrational desires designed to show that means/end conceptions are inadequate simply appeal to our intuitions and many will not share those intuitions in all cases. The intuitive appeal of instrumental theories will be bolstered if it is emphasized that they do not permit the pursuit of every fleeting desire, but rather those which the agent herself deems most important. There are no sufficient grounds for a rejection of instrumentalism. Attempts at alternative views either collapse into instrumentalist accounts or they fail to provide the principles needed to establish a satisfactory account of rationality applicable to all agents.

<p> This thesis considers how Martin Heidegger treats &ldquo;wonder&rdquo; (<i>thaumazein</i>) in Plato and Aristotle versus how it appears to be treated by them. The introduction outlines how the problem of wonder arises when Heidegger mentions particular instances from Plato&rsquo;s <i> Theaetetus</i> and Aristotle&rsquo;s <i>Metaphysics</i> as the basis for his claim that philosophy originates in wonder. In chapter one, I analyze each of the twenty-four occurrences of wonder in Plato&rsquo;s <i> Theaetetus</i>, beginning with a preliminary discussion of Heidegger&rsquo;s delimitation of wonder from the wondrous. In chapter two, I examine the relation between philosophy and wonder in chapters one and two of Book Alpha of Aristotle&rsquo;s <i> Metaphysics.</i> In chapter three, I begin by considering Heidegger&rsquo;s later lecture, <i>What is that&mdash;Philosophy?</i>, before turning to his earlier writing, <i>The Need and Necessity of the First Beginning and the Need and Necessity of an Other Way to Question and to Begin.</i> I end by reflecting on Heidegger&rsquo;s account of pre-Socratic versus Socratic philosophy in these writings and consider how Leo Strauss seems to provide an alternative to Heidegger&rsquo;s analysis. Finally, in the conclusion, I discuss the relation between wonder and Eros in Plato and Aristotle.</p>