How do we ascribe subjective probability? In decision theory, this question is often addressed by representation theorems, going back to Ramsey (1926), which tell us how to define or measure subjective probability by observable preferences. However, standard representation theorems make strong rationality assumptions, in particular expected utility maximization. How do we ascribe subjective probability to agents which do not satisfy these strong rationality assumptions? I present a representation theorem with weak rationality assumptions which can be used to define or measure (...) subjective probability for partly irrational agents. (shrink)

Is more information always better? Or are there some situations in which more information can make us worse off? Good (1967) argues that expected utility maximizers should always accept more information if the information is cost-free and relevant. But Good's argument presupposes that you are certain you will update by conditionalization. If we relax this assumption and allow agents to be uncertain about updating, these agents can be rationally required to reject free and relevant information. Since there are good reasons (...) to be uncertain about updating, rationality can require you to prefer ignorance. (shrink)

In her 1993 book Freedom within Reason, Susan Wolf discusses what she identifies as an asymmetry between the good and the bad: to qualify as doing good in a praiseworthy way, it is not necessary that one should have the ability to do otherwise, but in order to qualify as doing something bad in a blameworthy way, it is necessary that one has the ability to do otherwise. In this chapter, I relate this asymmetry between the good and the bad (...) that Wolf discusses to a range of other asymmetries between the good and the bad that various philosophers – both historical figures and contemporary philosophers – have identified. I discuss different ways of thinking about the relations among these supposed asymmetries between the good and the bad, identify different ways in which one can relate to these ideas in one’s philosophical thinking, and lastly also argue that the long history of philosophical reflections on asymmetries between the good and the bad is interesting to contemporary discussions within applied ethics. In particular, I relate these ideas about asymmetries between the good and the bad to contemporary discussions about moral responsibility – and possible gaps in responsibility – within the ethics of artificial intelligence. (shrink)

I explain the New Riddle of Induction (Goodman 1946, 1955) in very brief words.

Many of our sources of knowledge only afford us knowledge that is inexact. When trying to see how tall something is, or to hear how far away something is, or to remember how long something lasted, we may come to know some facts about the approximate size, distance or duration of the thing in question but we don’t come to know exactly what its size, distance or duration is. In some such situations we also have some pointed knowledge of how (...) inexact our knowledge is. That is, we can knowledgeably pinpoint some exact claims that we do not know. We show that standard models of inexact knowledge leave little or no room for such pointed knowledge. We devise alternative models that are not afflicted by this shortcoming. (shrink)

The framework of Solomonoff prediction assigns prior probability to hypotheses inversely proportional to their Kolmogorov complexity. There are two well-known problems. First, the Solomonoff prior is relative to a choice of Universal Turing machine. Second, the Solomonoff prior is not computable. However, there are responses to both problems. Different Solomonoff priors converge with more and more data. Further, there are computable approximations to the Solomonoff prior. I argue that there is a tension between these two responses. This is because computable (...) approximations to Solomonoff prediction do not always converge. (shrink)

In diesem Aufsatz stelle ich eine neue Interpretation der Reinhold’schen Sprachphilosophie vor. Mein Ziel ist es zu erklären, wie Reinhold der Meinung sein konnte, seine Sprachphilosophie stelle, ebenso wie seine Elementarphilosophie, den Versuch dar, Kants Kritische Philosophie zu fundieren. Außerdem möchte ich zeigen, worin die philosophische Bedeutung von Reinholds Ansatz gegenüber den Sprachphilosophien seiner Zeitgenossen besteht.

How might emerging and future technologies—sex robots, love drugs, anti-love drugs, or algorithms to track, quantify, and ‘gamify’ romantic relationships—change how we understand and value love? We canvass some of the main ethical worries posed by such technologies, while also considering whether there are reasons for “cautious optimism” about their implications for our lives. Along the way, we touch on some key ideas from the philosophies of love and technology.

The absence of meaningfulness in life is meaninglessness. But what is the polar opposite of meaningfulness? In recent and ongoing work together with Stephen Campbell and Marcello di Paola respectively, I have explored what we dub ‘anti-meaning’: the negative counterpart of positive meaning in life. Here, I relate this idea of ‘anti-meaningful’ actions, activities, and projects to the topic of death, and in particular the deaths or suffering of those who will live after our own deaths. Connecting this idea of (...) anti-meaning and what happens after our own deaths to recent work by Samuel Scheffler on what he calls ‘the collective afterlife’ and his four reasons to care about future generations, I argue that if we today make choices or have lifestyles that later lead to unnecessarily early deaths and otherwise avoidable suffering of people who will live after we have died, this robs our current choices and lifestyles of some of their meaning, perhaps even making them the opposite of meaningful in the long run. (shrink)

Chancy modus ponens is the following inference scheme: ‘probably φ’, ‘if φ, then ψ’, therefore, ‘probably ψ’. I argue that Chancy modus ponens is invalid in general. I further argue that the invalidity of Chancy modus ponens sheds new light on the alleged counterexample to modus ponens presented by McGee. I close by observing that, although Chancy modus ponens is invalid in general, we can recover a restricted sense in which this scheme of inference is valid.

Christine M. Korsgaard ist eine der einflussreichsten Stimmen der Gegenwartsphilosophie. In ihren Arbeiten zur Moralphilosophie Kants verteidigt sie diese gegen zwei Einwände: erstens, dass der kategorische Imperativ auf externe Werte angewiesen ist, mithin als formales Testverfahren scheitere, und, zweitens, dass Kant empfindungsfähige Wesen, die kein Vernunftvermögen besitzen, aus seiner Ethik ausgeschlossen habe und ausschließen musste. Den ersten Einwand glaubt Korsgaard durch eine spezifische Interpretation des kantischen Widerspruchsverständnisses zumindest partiell zurückweisen zu können. Wie ich zeigen werde, unterschätzt Korsgaard allerdings die Probleme, (...) die die Allgemeine Formel des kategorischen Imperativs mit sich bringt. Den zweiten Einwand wiederum glaubt Korsgaard in Form einer immanenten Kritik entkräften zu können: Kant selbst hätte auf Grundlage seines transzendentalen Arguments für die Selbstzweckformel zu dem Schluss kommen können, dass Tiere Zwecke an sich sind. Meine Thesen lauten, (a) dass Korsgaards Kant-Auslegung nicht vom Text gedeckt ist, (b) ihr Regress-upon-the-conditions-Argument nicht zur Begründung einer interpersonellen Moral taugt und es (c) auch tierethisch nicht zum gewünschten Ziel führt. (shrink)

It has long been known that memory need not be a literal reproduction of the past but may be a constructive process. To say that memory is a constructive process is to say that the encoded content may differ from the retrieved content. At the same time, memory is bound by the authenticity constraint which states that the memory content must be true to the subject's original perception of reality. This paper addresses the question of how the constructive nature of (...) visual memory can be reconciled with the authenticity constraint. In what respect and to what extent may the content of a visual memory differ from the original perceptual state while still adequately reflecting the subject's original perception? (shrink)

In this paper I argue in favor of the compatibility of semantic externalism with privileged self-knowledge by showing that an argument for incompatibilism from switching scenarios fails. Given the inclusion theory of self-knowledge, the hypothesis according to which I am having twater thoughts while thinking that I have water thoughts simply isn't a (entertainable) possibility. When I am on Earth thinking earthian concepts, I cannot believe that I am thinking that twater is wet for I don't have the concept of (...) twater available; so this concept cannot figure in any of my mental states. Analogously, when I am on Twin Earth, I cannot mistakenly believe that I am entertaining water thoughts. No matter how often I am switched between Earth and Twin Earth, I will never erroneously think that I am having water thoughts while in fact I am having twater thoughts and vice versa. Privileged self-knowledge is therefore immune to skeptical arguments from switching and twinning scenarios. (shrink)

What is a concept? Philosophers have given many different answers to this question, reflecting a wide variety of approaches to the study of mind and language. Nonetheless, at the most general level, there are two dominant frameworks in contemporary philosophy. One proposes that concepts are mental representations, while the other proposes that they are abstract objects. This paper looks at the differences between these two approaches, the prospects for combining them, and the issues that are involved in the dispute. We (...) argue that powerful motivations have been offered in support of both frameworks. This suggests the possibility of combining the two. Unlike Frege, we hold that the resulting position is perfectly coherent and well worth considering. Nonetheless, we argue that it should be rejected along with the view that concepts are abstract objects. (shrink)

In this paper, I develop a novel account of concept acquisition for an atomistic theory of concepts. Conceptual atomism is rarely explored in cognitive science because of the feeling that atomistic treatments of concepts are inherently nativistic. My model illustrates, on the contrary, that atomism does not preclude the learning of a concept.

In this paper, we engage in dialogue with Jonathan Pugh, Hannah Maslen, and Julian Savulescu about how to best interpret the potential impacts of deep brain stimulation on the self. We consider whether ordinary people’s convictions about the true self should be interpreted in essentialist or existentialist ways. Like Pugh et al., we argue that it is useful to understand the notion of the true self as having both essentialist and existentialist components. We also consider two ideas from existentialist philosophy (...) – Jean-Paul Sartre and Simone de Beauvoir’s ideas about “bad faith” and “ambiguity” – to argue that there can be value to patients in regarding themselves as having a certain amount of freedom to choose what aspects of themselves should be considered representative of their true selves. Lastly, we consider the case of an anorexia nervosa-patient who shifts between conflicting mind-sets. We argue that mind-sets in which it is easier for the patient and his or her family to share values can plausibly be considered to be more representative of the patient’s true self, if this promotes a well-functioning relationship between the patient and the family. However, we also argue that families are well-advised to give patients room to figure out what such shared values mean to them, since it can be alienating for patients if they feel that others try to impose values on them from the outside. (shrink)

While Spelke provides powerful support for concept nativism, her focus on understanding concept nativism through six innate core knowledge systems is too confining. There is also no reason to suppose that thecurse of a compositional mindconstitutes a principled reason for positing less innate structure in explaining the origins of concepts. Any solution to such problems must take into account poverty of the stimulus considerations, which argue for postulating more innate structure, not less.

PurposeIn this article, we aim to present and defend a contextual approach to mathematical explanation.MethodTo do this, we introduce an epistemic reading of mathematical explanation.ResultsThe epistemic reading not only clarifies the link between mathematical explanation and mathematical understanding, but also allows us to explicate some contextual factors governing explanation. We then show how several accounts of mathematical explanation can be read in this approach.ConclusionThe contextual approach defended here clears up the notion of explanation and pushes us towards a pluralist vision (...) on mathematical explanation. (shrink)

It is a mistake to think that we cannot be morally responsible for forgetting because, as a matter of principle, forgetting is outside of our control. Sometimes we do have control over our forgetting. When forgetting is under our control there is no question that it is the proper object of praise and blame. But we can also be morally responsible for forgetting something when it is beyond our control that we forget that thing. The literature contains three accounts of (...) the blameworthiness of forgetting over which the agent has no control—the tracing account, the liberalized awareness condition, and attributionism. Even though these are competing accounts of the blameworthiness of harmful forgetting they are compatible with one another. In particular, it is possible to come up with a position that endorses the tracing account for certain kinds of harmful forgetting and attributionism for other kinds of harmful forgetting. (shrink)

Ramsey (1926) sketches a proposal for measuring the subjective probabilities of an agent by their observable preferences, assuming that the agent is an expected utility maximizer. I show how to extend the spirit of Ramsey's method to a strictly wider class of agents: risk-weighted expected utility maximizers (Buchak 2013). In particular, I show how we can measure the risk attitudes of an agent by their observable preferences, assuming that the agent is a risk-weighted expected utility maximizer. Further, we can leverage (...) this method to measure the subjective probabilities of a risk-weighted expected utility maximizer. (shrink)

Advocates of dynamic systems have suggested that higher mental processes are based on continuous representations. In order to evaluate this claim, we first define the concept of representation, and rigorously distinguish between discrete representations and continuous representations. We also explore two important bases of representational content. Then, we present seven arguments that discrete representations are necessary for any system that must discriminate between two or more states. It follows that higher mental processes require discrete representations. We also argue that discrete (...) representations are more influenced by conceptual role than continuous representations. We end by arguing that the presence of discrete representations in cognitive systems entails that computationalism (i.e., the view that the mind is a computational device) is true, and that cognitive science should embrace representational pluralism. (shrink)

This paper argues for a noncognitiveist computationalism in the philosophy of mind. It further argues that both humans and computers have intentionality, that is, their mental states are semantical -- they are about things in their worlds.

In some recent works, Crupi and Iacona have outlined an analysis of ‘if’ based on Chrysippus’ idea that a conditional holds whenever the negation of its consequent is incompatible with its antecedent. This paper presents a sound and complete system of conditional logic that accommodates their analysis. The soundness and completeness proofs that will be provided rely on a general method elaborated by Raidl, which applies to a wide range of systems of conditional logic.

One relatively neglected challenge in ethical artificial intelligence (AI) design is ensuring that AI systems invite a degree of emotional and moral concern appropriate to their moral standing. Although experts generally agree that current AI chatbots are not sentient to any meaningful degree, these systems can already provoke substantial attachment and sometimes intense emotional responses in users. Furthermore, rapid advances in AI technology could soon create AIs of plausibly debatable sentience and moral standing, at least by some relevant definitions. Morally (...) confusing AI systems create unfortunate ethical dilemmas for the owners and users of those systems, since it is unclear how those systems ethically should be treated. I argue here that, to the extent possible, we should avoid creating AI systems whose sentience or moral standing is unclear and that AI systems should be designed so as to invite appropriate emotional responses in ordinary users. (shrink)

I frame my argument by way of Hayek's tendency to treat Hume and Smith as central articulations of the rule of law. The rest of the paper explores their defense of clientelism. First, I introduce Hume’s ideas on the utility of patronage in his essay, “Of the Independency of Parliament.” I argue that in Hume clientelism just is a feature of parliamentary business. It seems ineliminable. I then contextualize Hume’s account by comparing it to Montesquieu’s account of this system of (...) patronage in Book XIX, chapter 27 of The Spirit of the Laws. Montesquieu primarily treats it as a species of bad corruption. However, he also sees some benefits to it. I then turn to Smith and I show that he echoes Hume’s analysis of corruption in an easily ignored passage in Wealth of Nations. I then show that for Smith one argument in favor of a kind of federal parliamentary union between Great Brittain and her American colonies lies in its ability to facilitate and make more efficient the system of patronage by the Crown. While Smith’s account of these matters is quite Humean, one can discern in Smith a distinct cost-benefit argument for the acceptance of the necessity of a system of patronage in the service of the peaceful expansion and entrenchment of the rule of law in his proposal for parliamentary union. (shrink)

Reuben Hersh confided to us that, about forty years ago, the late Paul Cohen predicted to him that at some unspecified point in the future, mathematicians would be replaced by computers. Rather than focus on computers replacing mathematicians, however, our aim is to consider the (im)possibility of human mathematicians being joined by “artificial mathematicians” in the proving practice—not just as a method of inquiry but as a fellow inquirer.

This paper, which is a homage to the life and work of Stephen Gaukroger, explores competing receptions of Spencer’s programmatic synthetic philosophy. In so doing, I show how T.H Huxley and C.S. Peirce reconfigured a familiar, long-standing debate about cosmogeny and cosmology in the early modern period.

My dissertation is about Bayesian rationality for non-ideal agents. I show how to derive subjective probabilities from preferences using much weaker rationality assumptions than other standard representation theorems. I argue that non-ideal agents might be uncertain about how they will update on new information and consider two consequences of this uncertainty: such agents should sometimes reject free information and make choices which, taken together, yield sure loss. The upshot is that Bayesian rationality for non-ideal agents makes very different normative demands (...) than ideal Bayesian rationality. (shrink)

An Artificially Intelligent system (an AI) has debatable moral personhood if it is epistemically possible either that the AI is a moral person or that it falls far short of personhood. Debatable moral personhood is a likely outcome of AI development and might arise soon. Debatable AI personhood throws us into a catastrophic moral dilemma: Either treat the systems as moral persons and risk sacrificing real human interests for the sake of entities without interests worth the sacrifice, or do not (...) treat the systems as moral persons and risk perpetrating grievous moral wrongs against them. The moral issues become even more perplexing if we consider cases of possibly conscious AI that are subhuman, superhuman, or highly divergent from us in their morally relevant properties. (shrink)

Advancements in artificial intelligence and (social) robotics raise pertinent questions as to how these technologies may help shape the society of the future. The main aim of the chapter is to consider the social and conceptual disruptions that might be associated with social robots, and humanoid social robots in particular. This chapter starts by comparing the concepts of robots and artificial intelligence and briefly explores the origins of these expressions. It then explains the definition of a social robot, as well (...) as the definition of humanoid robots. A key notion in this context is the idea of anthropomorphism: the human tendency to attribute human qualities, not only to our fellow human beings, but also to parts of nature and to technologies. This tendency to anthropomorphize technologies by responding to and interacting with them as if they have human qualities is one of the reasons why social robots (in particular social robots designed to look and behave like human beings) can be socially disruptive. As is explained in the chapter, while some ethics researchers believe that anthropomorphization is a mistake that can lead to various forms of deception, others — including both ethics researchers and social roboticists — believe it can be useful or fitting to treat robots in anthropomorphizing ways. The chapter explores that disagreement by, among other things, considering recent philosophical debates about whether social robots can be moral patients, that is, whether it can make sense to treat them with moral consideration. Where one stands on this issue will depend either on one’s views about whether social robots can have, imitate, or represent morally relevant properties, or on how people relate to social robots in their interactions with them. Lastly, the chapter urges that the ethics of social robots should explore intercultural perspectives, and highlights some recent research on Ubuntu ethics and social robots. (shrink)

At least since W. V. O. Quine's famous critique of the analytic/synthetic distinction, philosophers have been deeply divided over whether there are any analytic truths. One line of thought suggests that the simple fact that people have ' intuitions of analyticity' might provide an independent argument for analyticities. If defenders of analyticity can explain these intuitions and opponents cannot, then perhaps there are analyticities after all. We argue that opponents of analyticity have some unexpected resources for explaining these intuitions and (...) that, accordingly, the argument from intuition fails. (shrink)

There is a prevalent notion among cognitive scientists and philosophers of mind that computers are merely formal symbol manipulators, performing the actions they do solely on the basis of the syntactic properties of the symbols they manipulate. This view of computers has allowed some philosophers to divorce semantics from computational explanations. Semantic content, then, becomes something one adds to computational explanations to get psychological explanations. Other philosophers, such as Stephen Stich, have taken a stronger view, advocating doing away with semantics (...) entirely. This paper argues that a correct account of computation requires us to attribute content to computational processes in order to explain which functions are being computed. This entails that computational psychology must countenance mental representations. Since anti-semantic positions are incompatible with computational psychology thus construed, they ought to be rejected. Lastly, I argue that in an important sense, computers are not formal symbol manipulators. (shrink)

I argue that Smith proposed a new kind of imperialism, which we would describe as a species of ‘federalism,’ and that his plan influenced Bentham and Kant in their federal projects, although they seem to have been unaware of each other’s proposals. In what follows, I outline Smith’s position. I then describe Kant’s and Bentham’s debts to Smith in turn. This will also allow for greater clarity about the nature of early liberalism.

We examine a proposal for dealing with perhaps the chief difficulty facing holistic theories of meaning—meaning instability. The problem is that, given a robust holism, small changes in a representational system are likely to lead to meaning changes throughout the system. Consequently, different individuals are likely never to mean the same thing. Eric Lormand suggests that holists can avoid this problem—and even secure more stability than non-holists—by positing that symbols have multiple meanings. We argue that the proposal doesn't work, (...) however, since multiple meanings are unstable for much the same reason that single meanings are. (shrink)

In the Laws, Plato argues that legislation must not only compel, but also persuade. This is accomplished by prefacing laws with preludes. While this procedure is central to the legislative project of the dialogue, there is little interpretative agreement about the strategy of the preludes. This paper defends an interpretation according to which the strategy is to engage with citizens in a way that anticipates their progress toward a more mature evaluative outlook, and helps them grow into it. This paper (...) shall refer to this strategy as proleptic engagement. While the virtuous ways of life required by law are intimately connected to happiness, the preludes do not persuade by spelling out this connection. Rather, they persuade by telling citizens what they need to hear so that they can come to appreciate this connection for themselves, in the context of their own lives. While the preludes are many and varied, this paper argues that all preambular material can be understood as proleptic engagement. (shrink)

Could groups ever be an understanding subject (an epistemic agent ascribed with understanding) or should we keep our focus exclusively on the individuals that make up the group? The way this paper will shape an answer to this question is by starting from a case we are most willing to accept as group understanding, then mark out the crucial differences with an unconvincing case, and, ultimately, explain why these differences matter. In order to concoct the cases, however, we need to (...) elucidate what it means to be attributed with understanding and what makes up an epistemic agent. I shall argue that it is abilities, above all, that guide our attributions of understanding. While it is true that understanding must go beyond single acts, this is not going beyond as in going behind them (to private occurrences which are impossible to discern and don’t themselves contribute anything of value), but beyond as in considering what people could and would do: their discernable and valuable abilities. To conceptualize whom the abilities belong to, I will specify what it means to be an epistemic agent. I shall argue that it is being a successful target of the epistemic stance. The epistemic stance (heavily inspired by Dennett’s intentional stance) forms an instrumental abstraction by attributing epistemic properties (i.e., beliefs, epistemic aims, problem-solving tactics) to an entity to explain or predict its behavior. Macro-systematicity (a higher-level pattern which a theory can exploit) is what makes the epistemic stance’s abstraction an explanatory powerful one (regardless of how that macro-systematicity is realized) and emergence (the lack of a straightforward mapping-relation between the micro and the macro) is what makes its power unique to a particular level of explanation. To end, I suggest two kinds of mapping-relations and walk through the shift from reducibility to emergence. (shrink)

The thesis that mental states are physical states enjoys widespread popularity. After the abandonment of typeidentity theories, however, this thesis has typically been framed in terms of state tokens. I argue that token states are a philosopher’s fiction, and that debates about the identity of mental and physical state tokens thus rest on a mistake.

Après un examen des emplois antérieurs du terme « pseudotechnologie », une définition est proposée : « Une pseudotechnologie est une technologie présumée, irrémédiablement dysfonctionnelle pour l’usage auquel elle est destinée, puisqu’elle est basée sur des principes de construction qui ne peuvent pas être mis en œuvre ». La relation entre la pseudotechnologie et la pseudoscience est examinée, tout comme la relation entre la pseudotechnologie et le concept beaucoup plus faible de malfonction technologique. Une explication est proposée de la raison (...) pour laquelle la pseudotechnologie est beaucoup plus rarement mentionnée que la pseudoscience : le dysfonctionnement d’une technologie se manifeste généralement au moment de son utilisation, tandis que le dysfonctionnement d’une science est généralement plus difficile à établir. (shrink)

Hilary Putnam has famously argued that “we are brains in a vat” is necessarily false. The argument assumes content externalism (also known as semantic externalism and anti-individualism), that is, the view that the individuation conditions of mental content depend, in part, on external or relational properties of the subject’s environment. Recently content externalism has given rise to the hypothesis of the extended mind, whereby mental states are not only externally individuated but also externally located states. This chapter argues that when (...) content externalism is combined with the extended mind hypothesis it is robbed of its anti-skeptical power. Given the extended mind hypothesis, the supercomputer and the envatted brain can be regarded as aspects of the extended mind of the evil scientist. On this view, the thought contents of the coupled brain–computer–scientist system do not differ from those of a normal human. But without a difference in thought contents Putnam’s anti-skeptical argument crumbles. (shrink)

“What is the structure of thought?” is as central a question as any in cognitive science. A classic answer to this question has appealed to a Language of Thought (LoT). We point to emerging research from disparate branches of the field that supports the LoT hypothesis, but also uncovers diversity in LoTs across cognitive systems, stages of development, and species. Our letter formulates open research questions for cognitive science concerning the varieties of rules and representations that underwrite various LoT-based systems (...) and how these variations can help researchers taxonomize cognitive systems. (shrink)

To study conscious experience we must, to some extent, trust introspective reports; yet introspective reports often do not merit our trust. A century ago, E.B. Titchener advocated extensive introspective training as a means of resolving this difficulty. He describes many of his training techniques in his four-volume laboratory manual of 1901- 1905. This paper explores Titchener's laboratory manual with an eye to general questions about the prospects of introspective training for contemporary consciousness studies, with a focus on the following examples: (...) introspective knowledge of the combination tones that arise when a musical interval is played; the 'flight of colours' in the afterimage of a field of bright, broad- spectrum light; and the possibility of non-obvious visual illusions. Introspective training appears to have some merit, but also to involve significant hazards. (shrink)

Inquiry, Volume 57, Issue 1, Page 55-96, February 2014.

It is widely held that every person is a person essentially, where being a person is having special mental properties such as intelligence and self-consciousness. It follows that nothing can acquire or lose these properties. The paper argues that this rules out all familiar psychological-continuity views of personal identity over time. It also faces grave difficulties in accounting for the mental powers of human beings who are not intelligent and self-conscious, such as foetuses and those with dementia.