The counterfactual account of physical computation is simple and, for the most part, very attractive. However, it is usually thought to trivialize the notion of physical computation insofar as it implies ‘limited pancomputationalism’, this being the doctrine that every deterministic physical system computes some function. Should we bite the bullet and accept limited pancomputationalism, or reject the counterfactual account as untenable? Jack Copeland would have us do neither of the above. He attempts to thread a path between the two horns (...) of the dilemma by buttressing the counterfactual account with extra conditions intended to block certain classes of deterministic physical systems from qualifying as physical computers. His theory is called the ‘algorithm execution account’. Here we show that the algorithm execution account entails limited pancomputationalism, despite Copeland’s argument to the contrary. We suggest, partly on this basis, that the counterfactual account should be accepted as it stands, pancomputationalist warts and all. (shrink)

Famous examples of conceivability arguments include (i) Descartes’ argument for mind-body dualism, (ii) Kripke's ‘modal argument’ against psychophysical identity theory, (iii) Chalmers’ ‘zombie argument’ against materialism, and (iv) modal versions of the ontological argument for theism. In this paper, we show that for any such conceivability argument, C, there is a corresponding ‘mirror argument’, M. M is deductively valid and has a conclusion that contradicts C's conclusion. Hence, a proponent of C—henceforth, a ‘conceivabilist’—can be warranted in holding that C's premises (...) are conjointly true only if she can find fault with one of M's premises. But M's premises are modelled on a pair of C's premises. The same reasoning that supports the latter supports the former. For this reason, a conceivabilist can repudiate M's premises only on pain of severely undermining C's premises. We conclude on this basis that all conceivability arguments, including each of (i)–(iv), are fallacious. (shrink)

This paper concerns the three great modal dichotomies: (i) the necessary/contingent dichotomy; (ii) the a priori/empirical dichotomy; and (iii) the analytic/synthetic dichotomy. These can be combined to produce a tri-dichotomy of eight modal categories. The question as to which of the eight categories house statements and which do not is a pivotal battleground in the history of analytic philosophy, with key protagonists including Descartes, Hume, Kant, Kripke, Putnam and Kaplan. All parties to the debate have accepted that some categories are (...) void. This paper defends the contrary view that all eight categories house statements—a position I dub ‘octopropositionalism’. Examples of statements belonging to all eight categories are given. (shrink)

This is a review of Kris McDaniel's book, 'The Fragmentation of Being'. In the book McDaniel defends ontological pluralism -- the doctrine that there are multiple 'ways of being' (i.e., multiple modes, or degrees, or orders, or levels, or gradations of existence). In defending ontological pluralism, McDaniel must reject the rival, Quinean position that there is at root just one generic way for a thing to exist: viz., by its falling in the domain of unrestricted quantification. McDaniel argues against Quine (...) by contending that the unrestricted quantifier is really just shorthand for a ‘gruesome’ disjunction of restricted quantifiers. On McDaniel's view, the unrestricted quantifier plays ontological 'second fiddle' to these restricted quantifiers, which are ontologically fundamental, and which each represent one particular mode of being. Against this, I contend that if the disjunction in question was as gruesome as McDaniel makes out then logic would be apt to explode in our faces. If I am right then McDaniel's response to Quine falls flat. (shrink)

In Radicalizing Enactivism, D. D. Hutto and E. Myin develop a theory of mind they call ‘Radical Enactive (or Embodied) Cognition’ (REC). They argue that extant enactivist and embodied theories of mind are, although pretty radical, not radical enough, because such theories buy into the representationalist doctrine that perceptual experience (along with other forms of ‘basic’ mentality) possesses representational content. REC denies this doctrine. It implies that perceptual experience lacks reference, truth conditions, accuracy conditions, or conditions of satisfaction. In this (...) review I summarise their anti-representationalist argument and show that it has at least three major weaknesses. (shrink)

David Lewis describes, then attempts to refute, a simple anti-Humean theory of desire he calls ‘Desire as Belief’. Lewis’ critics generally accept that his argument is sound and focus instead on trying to show that its implications are less severe than appearances suggest. In this paper I argue that Lewis’ argument is unsound. I show that it rests on an essential assumption that can be straightforwardly proven false using ideas and principles to which Lewis is himself committed.

This chapter surveys and critically evaluates all the main arguments both for and against de-extinction. It presents a qualified defence of the claim that conservationists should embrace de-extinction. It ends with a list of do’s and don’ts for conservationist de-extinction projects.

Are the methods of synthetic biology capable of recreating authentic living members of an extinct species? An analogy with the restoration of destroyed natural landscapes suggests not. The restored version of a natural landscape will typically lack much of the aesthetic value of the original landscape because of the different historical processes that created it—processes that involved human intentions and actions, rather than natural forces acting over millennia. By the same token, it would appear that synthetically recreated versions of extinct (...) natural organisms will also be less aesthetically valuable than the originals; that they will be, in some strong sense, ‘inauthentic’, because of their peculiar history and mode of origin. I call this the ‘genesis argument’ against de-extinction. In this article I critically evaluate the genesis argument. I highlight an important disanalogy between living organisms and natural landscapes: viz., it is of the essence of the former, but not of the latter, to regularly reproduce and die. The process of iterated natural reproduction that sustains the continued existence of a species through time obviously does not undermine the authenticity of the species. I argue that the authenticity of a species will likewise be left intact by the kind of artificial copying of genes and traits that a de-extinction project entails. I conclude on this basis that the genesis argument is unsound. (shrink)

The title of Beth Shapiro’s ‘How to Clone a Mammoth’ contains an implicature: it suggests that it is indeed possible to clone a mammoth, to bring extinct species back from the dead. But in fact Shapiro both denies this is possible, and denies there would be good reason to do it even if it were possible. The de-extinct ‘mammoths’ she speaks of are merely ecological proxies for mammoths—elephants re-engineered for cold-tolerance by the addition to their genomes of a few mammoth (...) genes. Shapiro’s denial that genuine species de-extinction is possible is based on her assumption that resurrected organisms would need to be perfectly indistinguishable from the creatures that died out. In this article I use the example of an extinct New Zealand wattlebird, the huia, to argue—contra Shapiro—that there are compelling reasons to resurrect certain species if it can be done. I then argue—again, contra Shapiro—that synthetically created organisms needn’t be perfectly indistinguishable from their genetic forebears in order for species de-extinction to be successful. (shrink)

How many attitudes must be posited at the level of reductive bedrock in order to reductively explain all the rest? Motivational Humeans hold that at least two attitudes are indispensable, belief and desire. Desire-As-Belief theorists beg to differ. They hold that the belief attitude can do the all the work the desire attitude is supposed to do, because desires are in fact nothing but beliefs of a certain kind. If this is correct it has major implications both for the philosophy (...) of mind, with regards the problem of naturalizing the propositional attitudes, and for metaethics, with regards Michael Smith’s ‘moral problem’. This paper defends a version of Desire-As-Belief, and shows that it is immune to several major objections commonly levelled against such theories. (shrink)

This chapter introduces the two main philosophical questions that are raised by the prospect of extinct species being brought back from the dead—namely, the ‘Authenticity Question’ and the ‘Ethical Question’. It distinguishes different types of de-extinction, and different methods by which de-extinction can be accomplished. Finally, it examines the aims of wildlife conservation with a view to whether they are compatible with de-extinction, or not.

This chapter examines three prime candidates for de-extinction—namely, the aurochs, the woolly mammoth, and the passenger pigeon. It will be about what these animals were like, why people want to resurrect them, and the methods by which their resurrections could be accomplished.

In this paper I argue that human beings should reason, not in accordance with classical logic, but in accordance with a weaker ‘reticent logic’. I characterize reticent logic, and then show that arguments for the existence of fundamental Gödelian limitations on artificial intelligence are undermined by the idea that we should reason reticently, not classically.

Is the resurrection of an extinct species genuinely possible, or not? Will organisms produced by de-extinction technology be authentic new members of the species that died out, or just convincing fakes? We seek to answer these questions in this chapter. Critics of de-extinction have offered many reasons for thinking that the products of de-extinction will be inauthentic. The bulk of the chapter is taken up with surveying their arguments. We attempt to show that none are convincing. We end the chapter (...) by offering and defending two arguments in favour of the view that authentic de-extinctions are possible. (shrink)

An unknown process is generating a sequence of symbols, drawn from an alphabet, A. Given an initial segment of the sequence, how can one predict the next symbol? Ray Solomonoff’s theory of inductive reasoning rests on the idea that a useful estimate of a sequence’s true probability of being outputted by the unknown process is provided by its algorithmic probability (its probability of being outputted by a species of probabilistic Turing machine). However algorithmic probability is a “semimeasure”: i.e., the sum, (...) over all x∈A, of the conditional algorithmic probabilities of the next symbol being x, may be less than 1. Prevailing wisdom has it that algorithmic probability must be normalized, to eradicate this semimeasure property, before it can yield acceptable probability estimates. This paper argues, to the contrary, that the semimeasure property contributes substantially to the power and scope of an algorithmic-probability-based theory of induction, and that normalization is unnecessary. (shrink)

Penrose [40] has discussed a new point of view concerning the nature of physics that might underline conscious thought processes. He has argued that it might be the case that some physical laws are not computable, i.e. they cannot be properly simulated by computer; such laws can most probably arise on the “no-man’s-land” between classical and quantum physics. Furthermore, conscious thinking is a non-algorithmic activity. He is opposing both strong AI , and Searle’s [47] contrary viewpoint mathematical “laws”).

This book is about the philosophy of de-extinction. -/- CHAPTER 1 introduces the two main philosophical questions that are raised by the prospect of extinct species being brought back from the dead—namely, the ‘Authenticity Question’ and the ‘Ethical Question’. It distinguishes the many different types and methods of de-extinction. Finally, it examines the aims of wildlife conservation with a view to whether they are compatible with de-extinction, or not. -/- CHAPTER 2 examines three prime candidates for de-extinction—namely, the aurochs, the (...) woolly mammoth, and the passenger pigeon. It is about what these animals were like, why people want to resurrect them, and the methods by which their resurrections could be accomplished. -/- CHAPTER 3 is about the authenticity of de-extinct animals. Critics of de-extinction have offered many reasons for thinking that the products of de-extinction will be inauthentic. The bulk of the chapter is taken up with surveying their arguments. We attempt to show that none are convincing, and end the chapter by offering and defending two arguments in favour of the view that authentic de-extinctions are possible. -/- CHAPTER 4 surveys and critically evaluates all the main arguments both for and against de-extinction. It presents a qualified defence of the claim that conservationists should embrace de-extinction. It ends with a list of do’s and don’ts for conservationist de-extinction projects. (shrink)