Causal Necessity in Aristotle

Like many realists about causation and causal powers, Aristotle uses the language of necessity when discussing causation, and he appears to think that by invoking necessity, he is clarifying the manner in which causes bring about or determine their effects. In so doing, he would appear to run afoul of Humean criticisms of the notion of a necessary connection between cause and effect. The claim that causes necessitate their effects may be understood— or attacked— in several ways, however, and so whether the view or its criticism is tenable depends on how we understand the necessitation claim. In fact, Aristotelian efficient causation may be said to involve two distinct necessary connections: one is a relation between causes considered as potential, while the other relates them considered as active. That is, the claims that (1) what has the power to heat necessarily heats what has the power to be heated, and that (2) a particular flame which is actually under a pot necessarily heats it, both of which appear to be true for Aristotle, involve distinct notions of necessity. The latter kind of necessity is based on the facts, as Aristotle sees them, about change, whereas the former is based in the nature of properties. Though different, both kinds of necessity are instances of what contemporary philosophers would call metaphysical necessity, and together they also amount to a theory of causal determination.     

Necessity, Sufficiency, and Perspective Effects in Causal Conditional Reasoning

A growing body of research indicates that in causal conditional reasoning, the conclusion that P is necessary for Q is suppressed where alternative conditions for Q are available. Similarly, the conclusion that P is sufficient for Q is suppressed where disabling conditions for P or additional requirements for Q are available. This paper describes experiments in which these factors were used to produce 'perspective effects' in causal contexts that appear identical to the perspective effects found in previous research with deontic tasks. It is therefore proposed that deontic perspective effects are themselves also attributable to the influence of pragmatic factors upon perceived necessity and sufficiency. A generalized theory based on a modification of the mental model theory of deontic reasoning is presented, which accounts for perspective effects across the two domains.     

Nosology and Causal Necessity; The Relation BetweenDefining a Disease and Discovering its Necessary Cause

The problem of disease definition is related to theproblem of proving that a certain agent is thenecessary cause of a certain disease. Natural kindterms like rheumatoid arthritis and AIDS refer toessences which are discoverable rather thanpredeterminate. No statement about such diseases isa priori necessarily true. Because theories onnecessary causes involve natural kind semantics,Koch's postulates cannot be used to falsify or verifysuch theories. Instead of proving that agent A is thenecessary cause of disease D, we include A in atheoretical definition of D, take this to representthe real meaning of D, and discard thepretheoretical definition. This is illustrated byKoch's own attempt to prove he had discovered thenecessary cause of tuberculosis. Methodologicalarguments about disease causation require a clear viewof our use of diagnostic terms. Medical lexicographersshould do more to provide such a view.     

Metaphysical Rationalism

The Principle of Sufficient Reason states that everything has an explanation. But different notions of explanation yield different versions of this principle. Here a version is formulated in terms of the notion of a “grounding” explanation. Its consequences are then explored, with particular emphasis on the fact that it implies necessitarianism, the view that every truth is necessarily true. Finally, the principle is defended from a number of objections, including objections to necessitarianism. The result is a defense of a “rationalist” metaphysics, one that constitutes an alternative to the contemporary dogmas that some aspects of the world are “metaphysically brute” and that the world could in so many ways have been different.     

Abstractions and Metaphysical Politics

Books reviewed in this article:
David Toole, Waiting for Godot in Sarajevo: Theological Reflections on Nihilism, Tragedy and Apocalypse     

No-Futurism and Metaphysical Contingentism

According to no-futurism, past and present entities are real, but future ones are not. This view faces a skeptical challenge (Bourne in Australas J Philos 80(3):359–371 2002; A future for presentism, Clarendon Press, Oxford 2006; Braddon-Mitchell in Analysis 64(283):199–203 2004): if no-futurism is true, how do you know you are present? I shall propose a new skeptical argument based on the physical possibility of Gödelian worlds (Albert Einstein: philosopher-scientist, Open Court, La Salle, pp. 555–562, 1949). This argument shows that a no-futurist has to endorse a metaphysical contingentist reading of no-futurism, the view that no-futurism is contingently true. But then, the no-futurist has to face a new skeptical challenge: how do you know that you are in a no-futurist world?     

Quantum Mechanics and Metaphysical Indeterminacy

There has been recent interest in formulating theories of non-representational indeterminacy. The aim of this paper is to clarify the relevance of quantum mechanics to this project. Quantum-mechanical examples of vague objects have been offered by various authors, displaying indeterminate identity, in the face of the famous Evans argument that such an idea is incoherent. It has also been suggested that the quantum-mechanical treatment of state-dependent properties exhibits metaphysical indeterminacy. In both cases it is important to consider the details of the metaphysical account and the way in which the quantum phenomenon is captured within it. Indeed if we adopt a familiar way of thinking about indeterminacy and apply it in a natural way to quantum mechanics, we run into illuminating difficulties and see that the case is far less straightforward than might be hoped.     

Causal Exclusion and Causal Bayes Nets

In this paper I reconstruct and evaluate the validity of two versions of causal exclusion arguments within the theory of causal Bayes nets. I argue that supervenience relations formally behave like causal relations. If this is correct, then it turns out that both versions of the exclusion argument are valid when assuming the causal Markov condition and the causal minimality condition. I also investigate some consequences for the recent discussion of causal exclusion arguments in the light of an interventionist theory of causation such as Woodward's ( 2003 ) and discuss a possible objection to my causal Bayes net reconstruction.