Stephen Mumford

Omissions are sometimes linked to responsibility. A harm can counterfactually depend on an omission to prevent it. If someone had the ability to prevent a harm but didn’t, this could suffice to ground their responsibility for the harm. Michael S. Moore’s claim is illustrated by the tragic case of Peter Parker, shortly after he became Spider-Man. Sick of being pushed around as a weakling kid, Peter became drunk on the power he acquired from the freak bite of a radioactive spider. When a police officer called to Spider-Man to stop an escaping burglar, which he could have done easily, he failed to act. He was through taking orders. The omission was followed by a crime. That very same burglar later robbed Peter’s own house and when challenged he shot dead Peter’s Uncle Ben. Later, Spider-Man tracked down the killer and, when seeing his face close up, the possibility of prevention dawned on him. He could have stopped this crook and had he done so Uncle Ben would still be alive. Stan Lee’s tale of power finished with a Shakespearean twist. Young Peter realised the truth of the WGPCGR-thesis: With Great Power Comes Great Responsibility. We too will endorse the WGPCGR-thesis. There is a close connection between our notions of moral and legal responsibility and the powers we have as causal agents. This will be particularly important when it comes to the case of omissions: where we had the power to act but failed to do so. We hope to show the connections between the notions of power, cause, act, omission and responsibility but also some of the nuances. We will do so with particular reference to Moore’s account in Causation and Responsibility.

Is the world of appearances the real world? Are there facts that exist independently of our minds? Are there vague objects? _Russell on Metaphysics_ brings together for the first time a comprehensive selection of Russell's writing on metaphysics in one volume. Russell's major and lasting contribution to metaphysics has been hugely influential and his insights have led to the establishment of analytic philosophy as a dominant stream in philosophy. Stephen Mumford chronicles the metaphysical nature of these insights through accessible introductions to the texts, setting them in context and understanding their continued importance. _Russell on Metaphysics_ is both a valuable introduction to Bertrand Russell as a metaphysician, and an introduction to analytic philosophy and its history

Stephen Mumford puts forward a new theory of dispositions, showing how central their role is in metaphysics and philosophy of science. Much of our understanding of the physical and psychological world is expressed in terms of dispositional properties--from the solubility of sugar to the belief that zebras have stripes. Mumford discusses what it means to say that something has a property of this kind, and how dispositions can possibly be real things in the world. His clear, straightforward, realist account reveals them to be less mysterious than they seem, and shows that an understanding of dispositions is essential to an understanding of properties, causation, and scientific laws.

Hume thought that if you believed in powers, you believed in necessary connections in nature. He was then able to argue that there were none such because anything could follow anything else. But Hume wrong-footed his opponents. A power does not necessitate its manifestations: rather, it disposes towards them in a way that is less than necessary but more than purely contingent. -/- In this paper a dispositional theory of causation is offered. Causes dispose towards their effects and often produce them. But a set of causes, even though they may succeed in producing an effect, cannot necessitate it since the effect could have been counteracted by some additional power. This would require a separation of our concepts of causal production and causal necessitation. The most conspicuous cases of causation are those where powers accumulate and pass a requisite threshold for an effect to occur. -/- We develop a model for representing powers as constituent vectors within an n-dimensional quality space, where composition of causes appears as vector addition. Even our resultant vector, however, has to be understood as having dispositional force only. This model throws new light on causal modality and cases of prevention, causation by absence and probabilistic causation

What is the new essentialist asking us to accept? Not that there are natural kinds, nor that there are intrinsic causal powers. These things could be accepted without a commitment to essentialism. They are asking us to accept something akin to the Kripke‐Putnam position: a metaphysical theory about kind‐membership in virtue of essential properties. But Salmon has shown that there is no valid argument for the Kripke‐Putnam position: no valid inference that gets us from reference to essence. Why then should we accept essentialism? A remaining reason is Ellis's argument by display: we should buy essentialism because of the benefits it will bring. But are these benefits real? The problem is that the putative benefits of essentialism – that the laws of nature are necessary, that the problem of induction is solved, and so on – look actually to be the assumptions of Ellis's theory. If that is the case, there is no real benefit to be gained from adopting the theory. The argument for essentialism is therefore underdetermined and it remains possible to accept natural kinds into one's ontology without accepting their corresponding essences.

A standard way of representing causation is with neuron diagrams. This has become popular since the influential work of David Lewis. But it should not be assumed that such representations are metaphysically neutral and amenable to any theory of causation. On the contrary, this way of representing causation already makes several Humean assumptions about what causation is, and which suit Lewis’s programme of Humean Supervenience. An alternative of a vector diagram is better suited for a powers ontology. Causation should be understood as connecting property types and tokens where there are dispositions towards some properties rather than others. Such a model illustrates how an effect is typically polygenous: caused by many powers acting with each other, and sometimes against each other. It models causation as a tendency towards an effect which can be counteracted. The model can represent cases of causal complexity, interference, over-determination and causation of absence (equilibrium).

This paper argues that the technical notion of conditional probability, as given by the ratio analysis, is unsuitable for dealing with our pretheoretical and intuitive understanding of both conditionality and probability. This is an ontological account of conditionals that include an irreducible dispositional connection between the antecedent and consequent conditions and where the conditional has to be treated as an indivisible whole rather than compositional. The relevant type of conditionality is found in some well-defined group of conditional statements. As an alternative, therefore, we briefly offer grounds for what we would call an ontological reading: for both conditionality and conditional probability in general. It is not offered as a fully developed theory of conditionality but can be used, we claim, to explain why calculations according to the RATIO scheme does not coincide with our intuitive notion of conditional probability. What it shows us is that for an understanding of the whole range of conditionals we will need what John Heil (2003), in response to Quine (1953), calls an ontological point of view.