Popper Seminar

Prioritarianism is often considered a preferable alternative to egalitarianism. However, seeing exactly what distinguishes these two views can be difficult. Prioritarianism says it is better to benefit the worse off (other things being equal). Egalitarianism says it is better to reduce inequality (other things being equal). But by benefiting the worse off we narrow the gap between them and the better off, thereby reducing inequality. The two views thus seem to go hand in hand. So what's the difference? Parfit illustrates this with an analogy. People at lower altitudes can breath more easily than those at higher altitudes, but the ease with which a person breathes depends only on her own altitude, not that of anyone else. Similarly, on prioritarianism, benefiting people at lower levels of well-being matters more than benefiting those at higher levels, but the extent to which benefiting a person matters depends only on her own well-being level, not that of anyone else. Egalitarianism disagrees: benefiting a person at a given level matters more when others are at a higher level; that is, when doing so has the effect of reducing inequality. One aim of this paper is to spell out the analogy more precisely. I argue that one natural way of doing this commits the prioritarian to a view about the betterness of uncertain prospects or lotteries, a view sometimes called 'ex post prioritarianism'. This view faces significant objections. It violates 'ex ante' versions of two plausible principles, the Pigou-Dalton Principle and the Pareto Principle. A second aim is to consider some responses to these objections.

In Constructing the World, David Chalmers aims to defend strong reductionist claims he calls “scrutability theses”. One such thesis says, roughly speaking, that every truth about the world could, in principle, be “read off” a complete list of the physical facts and the facts about conscious experience. However, his strategy for establishing such scrutability theses faces a fairly basic logical problem that has not previously been recognized: what I call the “problem of cross-family quantifications”. I argue that the problem is pervasive, and discuss potential ways to overcome it, including the assumption that the fundamental structure of the world lacks certain symmetries.

I argue that acyclicity of preference cannot be defended as a general requirement of instrumental rationality. The standard instrumentalist defence of the requirement to have acyclical preferences, namely the money pump argument, relies on a fatal equivocation about the standard of instrumental rationality. Instead, I show that on the most plausible view of the standard of instrumental rationality, acyclicity can be justified as a conditional requirement of instrumental rationality: It turns out to be a requirement of instrumental rationality for agents who have a desire to have choice dispositions that are stable over time and across different choice contexts. For the rest of us, instrumental rationality is more permissive.

Any statements we make in science are about some presumed entities (e.g., hormones, electrons, or the gross national product), unless it is a pure report of sensation within oneself. Entity-realism is prior to truth-realism, since it would not make sense to maintain that a statement about nature is true unless it speaks about real entities. Therefore it is necessary for realists to grapple with ontology in some basic sense. But how can we actually judge what is real? In a move partly inspired by Hacking, I propose a coherence theory of reality: we should, and usually do, consider as real the presumed referents of concepts that play a significant role in a coherent system of practice. This judgement of reality is internal to each system, and it is continuous with everyday usage as in “Ghosts aren’t real.” The demand for coherence rules out many things, but also rules in many things. In the absence of what else we might operationally mean by “real”, we should have the audacity to embrace the reality of many different kinds of things (as with Dupré’s “promiscuous realism”), even if the concepts referring to them belong to mutually incommensurable systems of practice. This is what we ought to do if we really take success as our only reliable guide in deciding what to be realist about.

Abstract: Leslie Stephen once wrote that “The pig has a stronger interest than anyone in the demand for bacon. If all the world were Jewish, there would be no pigs at all.”  In recent debates about the ethics of eating animals, some have advanced the related claim that if people cause animals to exist and give them good lives in…

Abstract: The isomorphism invariance criterion of logical nature has much to commend it. It can be philosophically motivated by the thought that logic is distinctively general or topic neutral. It is capable of precise set-theoretic formulation. And it delivers a plausible extension of ‘logical constant’ which respects the intuitively clear cases. Despite its attractions, the criterion has recently come under…

Abstract: David Papineau (2009) has posed a dilemma for the Fodorian picture of causal laws in the special sciences, involving multiply-realised causes and effects. If the causes are genuinely physically diverse, then their production of a common effect is coincidental; but if they share relevant physical features, it is reducible. Papineau acknowledges that selection offers an answer to this puzzle:…

Abstract: A number of philosophers have argued that certain epistemic norms can be justified by appeal to the fundamental value of truth or accuracy. In his recent monograph (Accuracy and the Laws of Credence, OUP 2016) Richard Pettigrew makes an impressive case for the comprehensive grounding of epistemology in the epistemic utility of accuracy together with standard principles of decision…

When people achieve knowledge of things by sharing mental resources, they think thoughts whose linguistic expression makes salient the use of the first-person plural pronoun, ‘we’. Jane Heal (2013) has argued that considerations about the relevance of acts of shared ('we') intentionality, or ‘co-cognition', suggest that the notion of mentality recommended by (social) anti-individualism ought to be privileged in accounts of psychological knowledge. In this paper, I challenge Heal’s argument by distinguishing two routes to understanding claims about the scope and philosophical significance of acts of co-cognition. Both routes lend credibility to aspects of an anti-individualistic view of the nature of thoughts about others’ minds. However, neither provides decisive support for the conclusion that a 'co-cognitivist' account of psychological concepts provides support for anti-individualism.

Today mental health is a universally valued outcome. It is prioritised by governments, hospitals, schools, employers, charities. And yet mental health appears to be prized more as a label than as a concept, because remarkably for a state so uncontroversially prized, it has no accepted definition. In this talk based on joint work with Sam Wren-Lewis I survey the existing explicit and implicit definitions. They turn out to be either too demanding (for example, the one by the World Health Organization which identifies mental health with a happy and productive community life) or not demanding enough (for example, mental health as the absence of diagnosable psychiatric disorder). I articulate the desiderata for a better definition and a potential candidate that meets them.

Abstract: Recently, a putative truism about explanation has come under increasing criticism. The putative truism is this: only obtaining facts and existing entities can explain. If the truism fails, then arguments for realism based on explanatory indispensability are also challenged. I will focus on what I take to be the strongest challenge to the putative truism; namely, the explanatory use of fictions and argue that it possible to rescue a limited version of the truism.

When dealing with incomplete preference or betterness orderings, expansion consistency condition beta is violated. As a result, incompleteness can give rise to dynamic inconsistency. This paper develops global choice principles that ensure dynamic consistency.

An infinite lottery machine induces a non-standard inductive logic that turns out to be the same logic appropriate to a problem in inductive inference arising in present theories of eternal inflation.

I argue that the aim of belief and the aim of science are both knowledge. The ‘aim of belief’ is to be identified with the product of a properly functioning cognitive system. Science is an institution that is the social, functional analogue of a cognitive system, and its aim is the same as that of belief. In both cases it is knowledge rather than true belief that is the product of proper functioning.

Sometimes one ends up in an unfortunate situation when you cannot come to a stable opinion: whatever belief you adopt makes you want to change your mind. I suggest that in such scenarios you should adopt imprecise probabilities.

Abstract: In the first part of the talk we review and critically evaluate the received view of physical possibility. In the second part we sketch two alternative approaches – a metaphysical and an epistemic – to physical possibility which aim to be compatible with actualism, eternalism, humeanism, as well as with a simplistic inductive picture of confirming physical theories.

Assertions are, speaking roughly, descriptive statements which purport to describe some fact about the world. Philosophers have given a lot of attention to the idea that assertions come with special norms governing their behaviour. Frequently, in fact, philosophers claim that for something to count as an assertion it has to be governed by these norms. So what exactly are the norms of assertion? Here there is disagreement. Some philosophers believe assertions are governed by special factive norms, to the effect that an assertion must be true, or known to be true, or known with certainty to be true - or in any case that an assertion is normatively good just in case it meets some condition that entails its truth. Other philosophers place weaker epistemic constraints on good assertion. For instance the claim that an assertion is justified given the assertor's evidence. We argue that no such norm could apply to a special class of scientific utterances - namely, the conclusions of scientific papers, or more generally the sort of utterances scientists use to communicate the results of their inquiry. Such utterances might look like paradigm instances of descriptive statements purporting to describe some fact, yet the norms of assertion philosophers have surveyed are systematically inapt for science. Hence, either philosophers are generally wrong about these norms, or strictly speaking scientists should not be considered to be making assertions at all when they report their results. After surveying our argument for this negative claim, we end by suggesting a norm of utterance that would be more appropriate to scientific practice.