Peter Menzies

(1953 - 2015)

The so-called Canberra Plan is a grandchild of the Ramsey-Carnap treatment of theoretical terms. In its original form, the Ramsey-Carnap approach provided a method for analysing the meaning of scientific terms, such as “electron”, “gene” and “quark”—terms whose meanings could plausibly be delineated by their roles within scientific theories. But in the hands of David Lewis (1970, 1972), the original approach begat a more ambitious descendant, generalised and extended in two distinct ways: first, Lewis applied the technique to analyse the meaning of terms introduced not just by explicit scientific theories, but also by implicit folk theories such as folk psychology; second, he supplemented the theory to provide an account of the way in which the referents of the analysed terms might be identified on the basis of empirical investigation.

We offer a critical assessment of the “exclusion argument” against free will, which may be summarized by the slogan: “My brain made me do it, therefore I couldn't have been free”. While the exclusion argument has received much attention in debates about mental causation (“could my mental states ever cause my actions?”), it is seldom discussed in relation to free will. However, the argument informally underlies many neuroscientific discussions of free will, especially the claim that advances in neuroscience seriously challenge our belief in free will. We introduce two distinct versions of the argument, discuss several unsuccessful responses to it, and then present our preferred response. This involves showing that a key premise – the “exclusion principle” – is false under what we take to be the most natural account of causation in the context of agency: the difference-making account. We finally revisit the debate about neuroscience and free will.

The systems studied in the special sciences are often said to be causally autonomous, in the sense that their higher-level properties have causal powers that are independent of the causal powers of their more basic physical properties. This view was espoused by the British emergentists, who claimed that systems achieving a certain level of organizational complexity have distinctive causal powers that emerge from their constituent elements but do not derive from them. More recently, non-reductive physicalists have espoused a similar view about the causal autonomy of special-science properties. They argue that since these properties can typically have multiple physical realizations, they are not identical to physical properties, and further they possess causal powers that differ from those of their physical realisers. Despite the orthodoxy of this view, it is hard to find a clear exposition of its meaning or a defence of it in terms of a well-motivated account of causation. In this paper, we aim to address this gap in the literature by clarifying what is implied by the doctrine of the causal autonomy of special-science properties and by defending the doctrine using a prominent theory of causation from the philosophy of science.

Causation is a central topic in many areas of philosophy. In metaphysics, philosophers want to know what causation is, and how it is related to laws of nature, probability, action, and freedom of the will. In epistemology, philosophers investigate how causal claims can be inferred from statistical data, and how causation is related to perception, knowledge and explanation. In the philosophy of mind, philosophers want to know whether and how the mind can be said to have causal efficacy, and in ethics, whether there is a moral distinction between acts and omissions and whether the moral value of an act can be judged according to its consequences. And causation is a contested concept in other fields of enquiry, such as biology, physics, and the law. This book provides an in-depth and comprehensive overview of these and other topics, as well as the history of the causation debate from the ancient Greeks to the logical empiricists. The chapters provide surveys of contemporary debates, while often also advancing novel and controversial claims; and each includes a comprehensive bibliography and suggestions for further reading. The book is thus the most comprehensive source of information about causation currently available, and will be invaluable for upper-level undergraduates through to professional philosophers.

It is often argued that higher-level special-science properties cannot be causally efficacious since the lower-level physical properties on which they supervene are doing all the causal work. This claim is usually derived from an exclusion principle stating that if a higher-level property F supervenes on a physical property F* that is causally sufficient for a property G, then F cannot cause G. We employ an account of causation as difference-making to show that the truth or falsity of this principle is a contingent matter and derive necessary and sufficient conditions under which a version of it holds. We argue that one important instance of the principle, far from undermining non-reductive physicalism, actually supports the causal autonomy of certain higher-level properties.

In this paper we defend the view that the ordinary notions of cause and effect have a direct and essential connection with our ability to intervene in the world as agents.1 This is a well known but rather unpopular philosophical approach to causation, often called the manipulability theory. In the interests of brevity and accuracy, we prefer to call it the agency theory.2 Thus the central thesis of an agency account of causation is something like this: an event A is a cause of a distinct event B just in case bringing about the occurrence of A would be an effective means by which a free agent could bring about the occurrence of B. In our view the unpopularity of the agency approach to causation may be traced to two factors. The first is a failure to appreciate certain distinctive advantages that this approach has over its various rivals. We have drawn attention to some of these advantages elsewhere, and we summarize below. However, the second and more important factor is the influence of a number of stock objections, objections that seem to have persuaded many philosophers that agency accounts face insuperable obstacles. In this paper we want to show that these objections have been vastly overrated. There are four main objections

CHAPTER ONE This thesis is a critical analysis of arguments which Michael Dummett has developed against realism. Dummett characterizes realism as the thesis that the meaning of sentences should be analyzed in terms of the notions oftruth and falsity which obey the classical principle of bivalence. Before examining Dummett's arguments against realism, I consider the two models Dummett proposes for analyzing the content of assertions and examine his thesis that the realist notion of truth is induced for some sentences by their use as constituents in compound sentences. CHAPTER TWO I begin the examination of Dummett's arguments against realism by noting that Dummett allows in his recent work that a Tarskian truth-theory, couched in terms of a non-classical notion of truth, may act within a theory of meaning as the theory of reference yielding an inductive specification of truth- conditions. I then present Dummett's distinction between modest and full- blooded theories of meaning and suggest that the difference between them lies in the fact that the latter type possesses, while the former type lacks, a theory of sense, which Dummett conceives of as a series of correlations between practical abilities and T-sentences. I then consider the manifestation form of the argument against realism and argue that it fails on several counts. I then consider the acquisition form of the argument and point out the disputable assumptions about language-acquisition on which it is based. In the concluding section I question whether a theory of meaning which makes due allowance for idealization in the study of semantic competence should require a theory of sense of the kind Dummett suggests and question why the theory of reference should be responsive to the particular practical abilities which Dumniett emphasizes. CHAPTER THREE In this chapter I complete the discussion of Dummett's arguments against realism and argue that Dummett has no satisfactory line of defence against my principal reaction to the manifestation form of the argument against realism. I then present Dummett's distinction between demonstrations and canonic al proofs his general distinction between between direct and indirect verifications. Then consider Dummett's attempts to characterize mathematical truth in terms of canonical proof and general truth in terms of direct verification. I conclude by outlining a problem which confronts a verificationist theory meaning of the kind Dummett espouses and show that there is a flaw in his argument that a verificationist theory of meaning leads to a rejection of classical logic. CHAPTER FOUR I begin this chapter by examining Dummett's claim that reductionism is neither necessary nor sufficient for anti-realism. I argue that there is a sense in which reductionism is necessary and claim that there is a way of uniformly characterizing anti-realist positions on a number of subjects in terms of the thesis that a sentence is true in virtue of the evidence existing for it. I then consider Dummett's claim that a realist interpretation of counterfactuals involves asserting the unrestricted validity of the law of conditional excluded middle. I conclude by arguing that the anti-realist cannot acknowledge the defeasibility of evidence for empirically undecidable sentences and at the same time meet a legitimate demand that he explain in terms which do not beg any questions his conception of truth for such sentences.

Non-reductive physicalism is the view that mental events cause other events in virtue of their mental properties and that mental properties supervene on, without being identical to, physical properties. Jaegwon Kim has presented several much-discussed arguments against this view. But the much simpler causal closure argument, which purports to establish that every mental property is identical to a physical property, has received less attention than Kim’s arguments. This paper aims to show how a non-reductive physicalist should rebut the causal closure argument. A crucial premise in the argument is a principle stating that the physical world is causally closed. It states, roughly, that every physical event has a physical sufficient cause. I argue that when the principle is formulated in this way, the causal closure argument is invalid. Less frequently, the causal closure principle is formulated in terms of a difference-making conception of causation so that it states that every physical effect has a physical difference-making cause. I argue that the principle, so formulated, is false and the causal closure argument unsound. Either way the argument lacks the apodeictic force to compel acceptance of its conclusion.

Newcomb's problem, first presented by Robert Nozick in 1969, has aroused much interest among philosophers because it appears to involve a conflict between two intuitively attractive principles of decision: the Principle of Dominance and the decision-rule of Richard Jeffrey's decision theory, the Principle of Maximizing Conditional Expected Utility. I believe that the Principle of Dominance makes the rational prescription in Newcomb's problem and, consequently, that the problem constitutes a counterexample to Jeffrey's theory. ;Setting aside the question whether Jeffrey's decision theory makes the right or wrong prescription in Newcomb's problem, it has many merits as a decision theory. In Chapter One, I describe some of these merits by comparing it with the 'standard' decision theory--namely, Savage's theory. In Chapter Two, I describe some other decision problems, inspired by Newcomb's problem, which have been presented as more plausible counterexamples to Jeffrey's theory. Following custom, I call these Newcomb decision problems. ;Philosophers who believe that Newcomb decision problems are genuine counterexamples to Jeffrey's theory diagnose the deficiency in Jeffrey's theory as consisting in the fact that it does not employ any causal notion in the calculation of expected utility: for this reason it does not accurately reflect the agent's causal beliefs. In the light of this diagnosis, several so-called 'causal decision theories' have been proposed as replacements for Jeffrey's theory. They are called 'causal decision theories' because causal notions enter into their calculations of expected utility. In Chapter Three, I describe two such causal decision theories; and in Chapters Four and Five, I consider the question whether they are equivalent. ;Shortly after the various causal decision theories were developed, several subtle and ingenious arguments were proposed to the effect that Newcomb's problem and Newcomb decision problems are not genuine counterexamples to Jeffrey's theory. These defences of Jeffrey's theory try to show that Jeffrey's decision-rule makes the same prescriptions as the causal decision-rules in the alleged counterexamples. In Chapters Six and Seven, I analyze, in detail, two defences along these lines; and in Chapter Eight, I present a general argument against any defence of Jeffrey's theory which attempts to reconcile Jeffrey's theory with causal decision theories.

You are asked to call out the letters on a chart during an eyeexamination: you see and then read out the letters ‘U’, ‘R’, and ‘X’. Commonsense says that your perceptual experiences causally control your calling out the letters. Or suppose you are playing a game of chess intent on winning: you plan your strategy and move your chess pieces accordingly. Again, commonsense says that your intentions and plans causally control your moving the chess pieces. These causal judgements are as plain and evident as any can be

Delusional beliefs have sometimes been considered as rational inferences from abnormal experiences. We explore this idea in more detail, making the following points. Firstly, the abnormalities of cognition which initially prompt the entertaining of a delusional belief are not always conscious and since we prefer to restrict the term “experience” to consciousness we refer to “abnormal data” rather than “abnormal experience”. Secondly, we argue that in relation to many delusions (we consider eight) one can clearly identify what the abnormal cognitive data are which prompted the delusion and what the neuropsychological impairment is which is responsible for the occurrence of these data; but one can equally clearly point to cases where this impairments is present but delusion is not. So the impairment is not sufficient for delusion to occur. A second cognitive impairment, one which impairs the ability to evaluate beliefs, must also be present. Thirdly (and this is the main thrust of our chapter) we consider in detail what the nature of the inference is that leads from the abnormal data to the belief. This is not deductive inference and it is not inference by enumerative induction; it is abductive inference. We offer a Bayesian account of abductive inference and apply it to the explanation of delusional belief.