This paper aims to address the question of how one ought to choose when one is uncertain about what outcomes will result from one’s choices, but when one can nevertheless assign probabilities to the different possible outcomes. These choices are commonly referred to as choices (or decisions) under risk. I assume in this paper that one ought to make instrumentally rational choices—more precisely, one ought to adopt suitable means to one’s morally permissible ends. Expected utility (EU) theory is generally accepted (...) as a normative theory of rational choice under risk, or, more specifically, as a theory of instrumental rationality. According to EU theory, when faced with a decision under risk, one ought to rank one’s options (from least to most choiceworthy) according to their EU and one ought to choose whichever option carries the greatest EU (or one of them in the event that several alternatives are tied). The EU of an option is a probability-weighted sum of each of its possible utilities. In this paper, I argue that EU theory is not the correct theory of instrumental rationality. In its place, I argue for a new theory of instrumental rationality, namely expected comparative utility (ECU) theory. I first show that for any choice option, a, and for any state of the world, G, the measure of the choiceworthiness of a in G is the comparative utility of a in G—that is, the difference in utility, in G, between a and whichever alternative to a carries the greatest utility in G. On the basis of this principle, I then argue, roughly speaking, that for any agent, S, faced with any decision under risk, S ought to rank her options (in terms of how choiceworthy they are) according to their ECU and S ought to choose whichever option carries the greatest ECU (or one of them in the event that several alternatives are tied). For any option, a, a’s ECU is a probability‐weighted sum of a’s comparative utilities across the various possible states of the world. In this paper, I show that in some commonplace decisions under risk, ECU theory delivers different verdicts from those of EU theory. (shrink)

In this paper, I argue for a new normative theory of rational choice under risk, namely expected comparative utility (ECU) theory. I first show that for any choice option, a, and for any state of the world, G, the measure of the choiceworthiness of a in G is the comparative utility (CU) of a in G—that is, the difference in utility, in G, between a and whichever alternative to a carries the greatest utility in G. On the basis of this (...) principle, I then argue that for any agent, S, faced with any decision under risk, S should rank his or her decision options (in terms of how choiceworthy they are) according to their comparative expected comparative utility (CECU) and should choose whichever option carries the greatest CECU. For any option, a, a's CECU is the difference between its ECU and that of whichever alternative to a carries the greatest ECU, where a's ECU is a probability-weighted sum of a's CUs across the various possible states of the world. I lastly demonstrate that in some ordinary decisions under risk, ECU theory delivers different verdicts from those of standard decision theory. (shrink)

In situations where we ignore everything but the space of possibilities, we ought to suspend judgment—that is, remain agnostic—about which of these possibilities is the case. This means that we cannot sum our degrees of belief in different possibilities, something that has been formalized as an axiom of non-additivity. Consistent with this way of representing our ignorance, I defend a doxastic norm that recommends that we should nevertheless follow a certain additivity of possibilities: even if we cannot sum degrees of (...) belief in different possibilities, we should be more confident in larger groups of possibilities. It is thus shown that, in the type of situation considered (in so-called ‘classical ignorance’, i.e. “behind a thin veil of ignorance”), it is epistemically rational for advocates of suspending judgment to endorse this comparative confidence; while on the other hand it is shown that, even in classical ignorance, no stronger belief—such as a precise uniform probability distribution—is warranted. (shrink)

Causation appears to present us with an interpretative difficulty. While arguably a redundant relation given fundamental physics, it is nevertheless apparently pragmatically indispensable. This chapter revisits certain arguments made previously by the author for these claims with the benefit of hindsight, starting with the role of causal models in the human sciences, and attempting to explain why it is not possible to straightforwardly ground such models in fundamental physics. This suggests that further constraints, going beyond physics, are needed to legitimate (...) such models. These supplementary constraints could be reified, but that would seem to conflict with the completeness of physics. A response is to emphasize the practical role of causal talk, and the author suggests that a fictionalist approach might be worth exploring. After clarifying fictionalism as a general approach, they carry out in some detail the project of clarifying what a fictionalist attitude to causation would involve. (shrink)

The dominant theory of the evolution of moral cognition across a variety of fields is that moral cognition is a biological adaptation to foster social cooperation. This chapter argues, to the contrary, that moral cognition is likely an evolutionary exaptation: a form of cognition where neurobiological capacities selected for in our evolutionary history for a variety of different reasons—many unrelated to social cooperation—were put to a new, prosocial use after the fact through individual rationality, learning, and the development and transmission (...) of social norms. This chapter begins with a brief overview of the emerging behavioral neuroscience of moral cognition. It then outlines a novel theory of moral cognition that I have previously argued explains these findings better than alternatives. Finally, it shows how the evidence for this theory of moral cognition and human evolutionary history together suggest that moral cognition is likely not a biological adaptation. Instead, like reading sheet music or riding a bicycle, moral cognition is something that individuals learn to do—in this case, in response to sociocultural norms created in our ancestral history and passed down through the ages to enable cooperative living. (shrink)

The notion of existential catastrophe is increasingly appealed to in discussion of risk management around emerging technologies, but it is not completely clear what this notion amounts to. Here, I provide an opinionated survey of the space of plausibly useful definitions of existential catastrophe. Inter alia, I discuss: whether to define existential catastrophe in ex post or ex ante terms, whether an ex ante definition should be in terms of loss of expected value or loss of potential, and what kind (...) of probabilities should be involved in any appeal to expected value. (shrink)

The paper focuses on the issue of compatibility of social institution and convention. At first, it introduces the modest account of conventionality building on five distinctive features – interdependence, arbitrariness, mind-independence, spontaneity, and normative-neutrality – which constitute conventional behaviour, then it presents the two major theories of social institutions that explain them in terms of rules, or equilibria. The argument is that conventions cover a wide-ranging area and cannot be identified with the category of institutions because it would be too (...) restrictive and contradictory to the initial modest account. (shrink)

A large body of research in cognitive psychology and neuroscience draws on Bayesian statistics to model information processing within the brain. Many theorists have noted that this research seems to be in tension with a large body of experimental results purportedly documenting systematic deviations from Bayesian updating in human belief formation. In response, proponents of the Bayesian brain hypothesis contend that Bayesian models can accommodate such results by making suitable assumptions about model parameters. To make progress in this debate, I (...) argue that it is fruitful to focus not on specific experimental results but rather on what I call the ‘sources of epistemic irrationality’ in human cognition. I identify four such sources and I explore whether and, if so, how Bayesian models can be reconciled with them: processing costs, evolutionary suboptimality, motivated cognition, and error management. 1 Introduction 2 The Bayesian Brain 3 The Problem of Epistemic Irrationality 3.1 Bayesian inference and rationality 3.2 Intuitive Bayesian inference 4 Sources of Epistemic Irrationality 4.1 Processing costs 4.2 Evolutionary suboptimality 4.3 Motivational influences 4.4 Error management 5 Conclusion. (shrink)

The focus of this study is cognitive choice: the selection of one cognitive option (a hypothesis, a theory, or an axiom, for instance) rather than another. The study proposes that cognitive choice should be based on the plausibilities of states posited by rival cognitive options and the utilities of these options' information outcomes. The proposal introduces a form of decision theory that is novel because comparative; it permits many choices among cognitive options to be based on merely comparative plausibilities and (...) utilities. This form of decision theory intersects with recommendations by advocates of decision theory for cognitive choice, on the one hand, and defenders of comparative evaluation of scientific hypotheses and theories, on the other. But it differs from prior decision-theoretic proposals because it requires no more than minimal precision in specifying plausibilities and utilities. And it differs from comparative proposals because none has shown how comparative evaluations can be carried out within a decision-theoretic framework. (shrink)

A common type of change in science occurs as theorists generalize a model of a phenomenon by removing some idealizations of the model. This type of change occurs in the decision sciences and also in the normative branch of the decision sciences that treats rational choice. After presenting a general ac-count of model generalization, the paper illustrates generalization of models in normative decision theory. The principal illustration generalizes a standard model of rational choice by removing the idealization that deliberation has (...) no cost. (shrink)

Scoring rules constitute a particularly popular technique for aggregating a set of rankings. However, setting the weights associated with rank positions is a crucial task, as different instantiations of the weights can often lead to different winners. In this work we adopt minimax regret as a robust criterion for determining the winner in the presence of uncertainty over the weights. Focusing on two general settings we provide a characterization of the minimax regret rule in terms of cumulative ranks, allowing a (...) quick computation of the winner. We then analyze the properties of using minimax regret as a social choice function. Finally we provide some test cases of rank aggregation using the proposed method. (shrink)

There are few models of price competition in a homogeneous-good market which permit general asymmetries of information amongst the sellers. This work studies a price game with discontinuous payoffs in which both costs and market demand are ex ante uncertain. The sellers evaluate uncertain profits with maximin expected utilities exhibiting ambiguity aversion. The buyers in the market are permitted to split between sellers tieing at the minimum price in arbitrary ways which may be deterministic or random. The role of the (...) primitives in determining equilibrium prices in the market is analyzed in detail. (shrink)

Precautionary Principles are often said to be appropriate for decision-making in contexts of uncertainty such as climate policy. Contexts of uncertainty are contrasted to contexts of risk depending on whether we have probabilities or not. Against this view, I argue that the risk-uncertainty distinction is practically irrelevant. I start by noting that the history of the distinction between risk and uncertainty is more varied than is sometimes assumed. In order to examine the distinction, I unpack the idea of having probabilities, (...) in particular by distinguishing three interpretations of probability: objective, epistemic, and subjective probability. I then claim that if we are concerned with whether we have probabilities at all—regardless of how low their epistemic credentials are—then we almost always have probabilities for policy-making. The reason is that subjective and epistemic probability are the relevant interpretations of probability and we almost always have subjective and epistemic probabilities. In contrast, if we are only concerned with probabilities that have sufficiently high epistemic credentials, then we obviously do not always have probabilities. Climate policy, for example, would then be a case of decision-making under uncertainty. But, so I argue, we should not dismiss probabilities with low epistemic credentials. Rather, when they are the best available probabilities our decision principles should make use of them. And, since they are almost always available, the risk-uncertainty distinction remains irrelevant. (shrink)

Pure time preference is a preference for something to come at one point in time rather than another merely because of when it occurs in time. In opposition to Sidgwick, Ramsey, Rawls, and Parfit we argue that it is not always irrational to be guided by pure time preferences. We argue that even if the mere difference of location in time is not a rational ground for a preference, time may nevertheless be a normatively neutral ground for a preference, and (...) this makes it plausible to claim that the preference is rationally permitted. (shrink)

This article addresses Taruek’s much discussed Number Problem from a non-consequentialist point of view. I argue that some versions of the Number Problem have no solution, meaning that no alternative is at least as choice-worthy as the others, and that the best way to behave in light of such moral indeterminacy is to let chance make the decision. I contrast my proposal with F M Kamm ’s nonconsequentialist argument for saving the greatest number, the Argument for Best Outcomes, which I (...) argue does not follow from the premises it is based on. (shrink)

Hare proposes a view he calls prospectism for making choices in situations in which preferences have a common, but problematic structure. I show that prospectism permits the decision-maker to make a series of choices she knows in advance will lead to a sure loss. I also argue that a theory that permits the decision-maker to make choices she knows in advance will lead to a sure loss should be rejected.

To consequentialise a moral theory means to account for moral phenomena usually described in nonconsequentialist terms, such as rights, duties, and virtues, in a consequentialist framework. This paper seeks to show that all moral theories can be consequentialised. The paper distinguishes between different interpretations of the consequentialiser’s thesis, and emphasises the need for a cardinal ranking of acts. The paper also offers a new answer as to why consequentialising moral theories is important: This yields crucial methodological insights about how to (...) pursue ethical inquires. (shrink)

Most ethical work is done at a low level of formality. This makes practical moral questions inaccessible to formal and natural sciences and can lead to misunderstandings in ethical discussion. In this paper, we use Bayesian inference to introduce a formalization of preference utilitarianism in physical world models, specifically cellular automata. Even though our formalization is not immediately applicable, it is a first step in providing ethics and ultimately the question of how to “make the world better” with a formal (...) basis. (shrink)

As artificial intelligence (AI) continues to proliferate into every area of modern life, there is no doubt that society has to think deeply about the potential impact, whether negative or positive, that it will have. Whilst scholars recognise that AI can usher in a new era of personal, social and economic prosperity, they also warn of the potential for it to be misused towards the detriment of society. Deliberate strategies are therefore required to ensure that AI can be safely integrated (...) into society in a manner that would maximise the good for as many people as possible, whilst minimising the bad. One of the most urgent societal expectations of artificial agents is the need for them to behave in a manner that is morally relevant, i.e. to become artificial moral agents (AMAs). In this article, I will argue that exemplarism, an ethical theory based on virtue ethics, can be employed in the building of computationally rational AMAs with weak machine ethics. I further argue that three features of exemplarism, namely grounding in moral exemplars, meeting community expectations and practical simplicity, are crucial to its uniqueness and suitability for application in building AMAs that fit the ethos of AI4SG. (shrink)

Auch in der Sozialen Arbeit stellt sich die Notwendigkeit, Entscheide ethisch legitimieren zu müssen. Nicht nur können durch ihre Interventionen hohe ethische Güter der betroffenen Person berührt sein, sondern zudem treten nicht selten auch Entscheidungssituationen auf, in denen die anstehende Entscheidung unsicher und umstritten ist. Anhand der erwachsenenschutzrechtlichen Seite der Kindes- und Erwachsenenschutzbehörde in der Schweiz werden wir in diesem Beitrag den Versuch unternehmen, John Rawls’ Überlegungsgleichgewicht in seinen Grundzügen in eine konkrete Praxis zu überführen mit dem Ziel, ethische Leitlinien (...) zur Entscheidungsfindung im Rahmen der KESB zu entwickeln. Dafür sind zunächst ein paar einleitende Bemerkungen zur KESB erforderlich, um ihre Spezifika zu skizzieren. Anschließend erfolgen einige Anmerkungen zu Herausforderungen der Entscheidungsfindung in der Praxis. Danach werden wir unser Modell in seinen Grundzügen umreißen und gesondert auf den Prozess der Deliberation eingehen, die in einem kollektiven Überlegungsgleichgewicht mündet. (shrink)

Ronald Dworkin's theory of equality of resources makes extensive use of markets. I show that all these markets rely on one specific neoclassical conception of the ideal market in full equilibrium, as analyzed by Debreu. This market must be understood as operating under circumstances of certainty, and this is incompatible with several components of Dworkin's account. In particular, it does not allow one to hold people responsible for their option luck, and it implies a high social safety net rather than (...) insurance schemes for addressing brute luck. I conclude by outlining an interpretation of equality of resources that takes the ideal market seriously. (shrink)

The Bhagavadgītā, part of the sixth book of the Hindu epic The Mahābhārata, offers a practical approach to mokṣa, or liberation, and freedom from saṃsāra, or the cycle of death and rebirth. According to the approach, known as karmayoga, salvation results from attention to duty and the recognition of past acts that inform the present and will direct the future. In the Bhagavadgītā, Kṛṣṇa advocates selfless action as the ideal path to realizing the truth about oneself as well as the (...) ultimate reality. Kṛṣṇa proclaims that humans have rights only to actions and not to their results, whether good or bad. Therefore, humans should not desire any results whatsoever. The prisoner’s dilemma is a fictional story that shows why individuals who seek only their personal benefit meet worse outcomes than those possible by cooperating with others. The dilemma provides an effective, albeit often overlooked, method for studying the Hindu principle of niṣkāmakarma that is arguably the central teaching of the Bhagavadgītā. In the context of the prisoner’s dilemma, a prisoner who wants to uphold niṣkāmakarma may choose one of two decision-making strategies: to be indifferent and leave the decision to chance or to either pursue the common good or the other person’s benefit instead of his or her own. Assuming that followers of niṣkāmakarma can be goal-oriented, the second strategy is more appropriate than the first, as long as one pursues unselfish goals and remains both indifferent and uncommitted to personal benefit. (shrink)

In “Experience and Time,” Brian Garrett poses a challenge to friends of the rationality of pure time preferences. In this discussion note, we accept the challenge and provide two kinds of cases wherein some pure time preferences could be deemed rational.

Innovative research on decision making under ‘deep uncertainty’ is underway in applied fields such as engineering and operational research, largely outside the view of normative theorists grounded in decision theory. Applied methods and tools for decision support under deep uncertainty go beyond standard decision theory in the attention that they give to the structuring of decisions. Decision structuring is an important part of a broader philosophy of managing uncertainty in decision making, and normative decision theorists can both learn from, and (...) contribute to, the growing deep uncertainty decision support literature. (shrink)

Historically, the hypothesis that our world is a computer simulation has struck many as just another improbable-but-possible “skeptical hypothesis” about the nature of reality. Recently, however, the simulation hypothesis has received significant attention from philosophers, physicists, and the popular press. This is due to the discovery of an epistemic dependency: If we believe that our civilization will one day run many simulations concerning its ancestry, then we should believe that we are probably in an ancestor simulation right now. This essay (...) examines a troubling but underexplored feature of the ancestor-simulation hypothesis: the termination risk posed by both ancestor-simulation technology and experimental probes into whether our world is an ancestor simulation. This essay evaluates the termination risk by using extrapolations from current computing practices and simulation technology. The conclusions, while provisional, have great implications for debates concerning the fundamental nature of reality and the safety of contemporary physics. (shrink)

John Rawls famously argued that the Difference Principle would be chosen by any rational agent in the original position. Derek Parfit and Philippe Van Parijs have claimed, contra Rawls, that it is not the Difference Principle which is implied by Rawls’ original position argument, but rather the more refined Lexical Difference Principle. In this paper, we study both principles in the context of social choice under ignorance. First, we present a general format for evaluating original position arguments in this context. (...) We argue that in this format, the Difference Principle can be specified in three conceptually distinct ways. We show that these three specifications give the same choice recommendations, and can be grounded in an original position argument in combination with the well-known maximin rule. Analogously, we argue that one can give at least four plausible specifications of the Lexical Difference Principle, which however turn out to give different recommendations in concrete choice scenarios. We prove that only one of these four specifications can be grounded in an original position argument. Moreover, this one specification seems the least appealing from the viewpoint of distributive justice. This insight points towards a general weakness of original position arguments. (shrink)

A common objection to the precautionary principle is that it is irrational. I argue that this objection goes beyond the often-discussed claim that the principle is incoherent. Instead, I argue, exp...

Does ‘remembering that p’ entail ‘knowing that p’? The widely-accepted epistemic theory of memory answers affirmatively. This paper purports to reveal the tension between ETM and the prevailing anti-luck epistemology. Central to my argument is the fact that we often ‘vaguely remember’ a fact, of which one plausible interpretation is that our true memory-based beliefs formed in this way could easily have been false. Drawing on prominent theories of misremembering in philosophy of psychology, I will construct cases where the subject (...) vaguely remembers that p while fails to meet the safety condition, which imply either that ETM is false or that safety is unnecessary for knowledge. The conclusion reached in this paper will be a conditional: if veritic epistemic luck is incompatible with knowledge, then ‘remembering that p’ does not entail ‘knowing that p’. (shrink)

When extended cognition is extended into mainstream epistemology, an awkward tension arises when considering cases of environmental epistemic luck. Surprisingly, it is not at all clear how the mainstream verdict that agents lack knowledge in cases of environmental luck can be reconciled with principles central to extended cognition.

Trends in corporate governance to minimize employee participation and to promote shareholder rights, in both the EU and US contexts, evidence the practical efficacy of the separation thesis and the dominance of models of corporate governance founded upon decision theory. Giving expression to a vision of human agency in terms of instrumental rationality, such models of corporate governance, presuppose clearly defined objectives. Drawing on the work of Talbot Brewer, Alasdair MacIntyre, and Robert Brandom, this paper offers an alternative practice-based model (...) of corporate governance that emphasizes the role of socially and historically embodied forms of reasoning in promoting a better understanding of the aims or objectives of the corporation, particularly with respect to the social, environmental, and economic context of the firm. After reviewing recent empirical literature concerning employee participation, criteria are offered concerning effective employee participation programs, as a means of implementing a practice-based model of corporate governance. (shrink)

Confronted with the possibility of severe environmental harms, such as catastrophic climate change, some researchers have suggested that we should abandon the principle at the heart of standard decision theory—the injunction to maximize expected utility—and embrace a different one: the Precautionary Principle. Arguably, the most sophisticated philosophical treatment of the Precautionary Principle is due to Steel. Steel interprets PP as a qualitative decision rule and appears to conclude that a quantitative decision-theoretic statement of PP is both impossible and unnecessary. In (...) this article, we propose a decision-theoretic formulation of PP in terms of lexical utilities. We show that this lexical model is largely faithful to Steel’s approach, but also that it corrects three problems with Steel’s account and clarifies the relationship between PP and standard decision theory. Using a range of examples, we illustrate how the lexical model can be used to explore a variety of issues related to precautionary reasoning. (shrink)

Probably many people have cyclic preferences: they prefer A to B, B to C and C to A for some objects of choice A, B and C. Recent work has resurrected the objection to cyclic preference that agents possessing them are open to exploitation by means of ‘money pumps’. The paper briefly reviews this work and proposes a general approach to problems of sequential choice that makes cyclic preference immune to exploitation by means of these new mechanisms.

Good’s theorem is the apparent platitude that it is always rational to ‘look before you leap’: to gather information before making a decision when doing so is free. We argue that Good’s theorem is not platitudinous and may be false. And we argue that the correct advice is rather to ‘make your act depend on the answer to a question’. Looking before you leap is rational when, but only when, it is a way to do this.

Lately, there has been an explosion of literature exploring the the relationship between one’s practical situation and one’s knowledge. Some involved in this discussion have suggested that facts about a person’s practical situation might affect whether or not a person knows in that situation, holding fixed all the things standardly associated with knowledge (like evidence, the reliability of one’s cognitive faculties, and so on). According to these “pragmatic encroachment” views, then, one’s practical situation encroaches on one’s knowledge. Though we won’t (...) endorse pragmatic encroachment here, we find the view intriguing, and it’s popularity warrants carefully considering it’s implications. One potential avenue of exploration concerns religious epistemology, in particular, whether pragmatic encroachment has consequences concerning the epistemic requirements of atheism. We begin the journey down that avenue by connecting Pascal’s Wager to pragmatic encroachment in order to defend this conditional: If there is pragmatic encroachment, then it is ceteris paribus more difficult to know that atheism is true (if it is) than it is to know that God exists (if God does exist). (shrink)

Decision-making has traditionally been modelled as a serial process, consisting of a number of distinct stages. The traditional account assumes that an agent first acquires the necessary perceptual evidence, by constructing a detailed inner repre- sentation of the environment, in order to deliberate over a set of possible options. Next, the agent considers her goals and beliefs, and subsequently commits to the best possible course of action. This process then repeats once the agent has learned from the consequences of her (...) actions and subsequently updated her beliefs. Under this interpretation, the agent’s body is considered merely as a means to report the decision, or to acquire the relevant goods. However, embodied cognition argues that an agent’s body should be understood as a proper part of the decision-making pro- cess. Accepting this principle challenges a number of commonly held beliefs in the cognitive sciences, but may lead to a more unified account of decision-making. This thesis explores an embodied account of decision-making using a recent frame- work known as predictive processing. This framework has been proposed by some as a functional description of neural activity. However, if it is approached from an embodied perspective, it can also offer a novel account of decision-making that ex- tends the scope of our explanatory considerations out beyond the brain and the body. We explore work in the cognitive sciences that supports this view, and argue that decision theory can benefit from adopting an embodied and predictive perspective. (shrink)

Over the centuries since the modern scientific revolution that started with Copernicus, Galileo, Kepler, and Newton, two things have changed that have required reorientation of our assumptions and re-education of our reflexes. First, we have learned that even the very best science is fallible; eminently successful theories investigated and supported through the best methods, and by the best evidence available, might be not just incomplete but wrong. That is, it is possible to have a justified belief that is false.

Die Übernahme des KI-Unternehmens DeepMind durch Google für rund eine halbe Milliarde US-Dollar signalisierte vor einem Jahr, dass von der KI-Forschung vielversprechende Ergebnisse erwartet werden. Spätestens seit bekannte Wissenschaftler wie Stephen Hawking und Unternehmer wie Elon Musk oder Bill Gates davor warnen, dass künstliche Intelligenz eine Bedrohung für die Menschheit darstellt, schlägt das KI-Thema hohe Wellen. Die Stiftung für Effektiven Altruismus (EAS, vormals GBS Schweiz) hat mit der Unterstützung von Experten/innen aus Informatik und KI ein umfassendes Diskussionspapier zu den Chancen (...) und Risiken der künstlichen Intelligenz verfasst und geht darin auf aktuelle, mittel- und langfristige Herausforderungen im Bereich der KI-Entwicklung ein. (shrink)

To be optimistic, it is standardly assumed, is to have positive expectations. I here argue that this definition is correct but captures only one variety of optimism – here called factual optimism. It leaves out two other important varieties of optimism. The first – focal optimism – corresponds to the idea of seeing the glass half full. The second – axiological optimism – consists in the view that good is stronger than bad. Those three varieties of optimism are irreducible to (...) each other and do not belong to a common kind. I define each of these, characterize their respective correctness conditions, and contrast hope with optimism. (shrink)

This thesis will utilise the literature on the distinction between doing harm and allowing harm to develop a novel system of moral sequencing that can be applied to general moral problems to decide if, when, and how an agent should intervene to prevent harm from occurring to another agent. Off the back of this discussion, this thesis will offer a way of determining the responsibility of certain agents for their actions within a moral sequence. These motivations will be at the (...) centre of the discussions in this thesis and will be accomplished by ultimately updating the system of moral sequencing so that it makes sense of practical cases of inner-agent change, which itself provides a justification for intervening earlier, and potentially diminishing the responsibility for agents who have experienced an inner-agent change, in a moral sequence. (shrink)

A choice function C is rational iff: if it allows a path through a sequence of decisions with a particular outcome, then that outcome is amongst the ones that C would have chosen from amongst all the possible outcomes of the sequence. This implies, and it is the strongest definition that implies, that anyone who is irrational could be talked out of their own preferences. It also implies weak but non-vacuous constraints on choices over ends. These do not include alpha (...) or beta. (shrink)

The Precautionary Principle (PP) is an influential principle of risk management. It has been widely introduced into environmental legislation, and it plays an important role in most international environmental agreements. Yet, there is little consensus on precisely how to understand and formulate the principle. In this paper I prove some impossibility results for two plausible formulations of the PP as a decision-rule. These results illustrate the difficulty in making the PP consistent with the acceptance of any trade-offs between catastrophic risks (...) and more ordinary goods. (shrink)