Ioannis G. Ntagkas

My dissertation aims to provide a formal semantic theory for metaphors and a computational model of that theory. A computer program, NETMET, implements the ideas presented in the dissertation. Working in a thoroughly cognitive manner, my dissertation is both rigorously mathematical and psychologically well-informed. The dissertation is scientific in method. The reasoning is primarily abductive, and each proposed hypothesis is validated against large, detailed examples from the history of philosophy and science. ;The dissertation begins by sketching a formal theory of conceptual knowledge. Conceptual knowledge is modeled as a semantic network of concepts: concepts are modeled as network nodes, propositions as structures containing such nodes. A semantic field is characterized as a cluster of densely interrelated concepts. ;The core of the dissertation is a formal theory of analogy. It is argued that analogies serve as the primary basis for the generation of metaphors. Analogies are viewed as approximate homomorphisms from a source semantic field to a target field. Constraint-satisfaction algorithms are presented for computing analogies and for transfering knowledge from the source to the target by means of an underlying analogy; particular care is taken to transfer the implicative structure of the source field. Such analogical transference produces metaphorical propositions. Rules are given for generating several syntactical forms of metaphorical utterances. ;The dissertation then proceeds to the analysis and interpretation of metaphors. Logical deep structures are provided for several syntactic forms of metaphors. For instance, copula metaphors are shown to be class-inclusion statements . A forward-chaining inference algorithm is presented that deduces literal propositions from metaphorical propositions. It is then shown how such literal entailments can be incorporated into abductive argument schema which confirm or disconfirm metaphors. In this respect, at least, metaphorical propositions are analogous to theoretical statements. Since arguments can be provided for metaphorical propositions, it is argued that they carry truth-values, and so are cognitively meaningful

There is a long history of philosophers granting a privileged epistemic status to cognition of directly present objects. In this paper, I examine three important historic accounts which provide different models of this cognitive state and its connection with its objects: that of the Stoics, who are corporealists and think that ordinary perception may have an epistemically privileged status, but who seem to struggle to accommodate non-perceptual cognizance; that of Augustine, who thinks that incorporeal objects are directly present to us in ‘intellectual perception’, and that, by way of contrast, ordinary sense-perception does not have a privileged epistemic status; and that of William of Ockham, who allows for unmediated action at a distance and is fairly generous about what counts as being directly present.

By means of the Ten Modes, Pyrrhonian skeptics appeal to conflicting appearances to bring about suspension of judgment. However, precisely how the skeptic might do so in a nondogmatic manner is not entirely clear. In this paper, I argue that existing accounts of the Modes face significant objections, and I defend an alternative account that better explains the logical structure, rational nature, and effectiveness of the Modes. In particular, I clarify how the Modes appeal to concerns about epistemic impartiality and circularity, the nature of the skeptic's nondoxastic attitude(s), and how the skeptic can employ the Modes nondogmatically.

This book attempts to contribute a historical and interpretive study of Descartes' epistemology. It provides a systematic and exhaustive clarification of the mysterious and puzzling doctrine of "clear and distinct perception" and illuminates the relationships between this doctrine and four other central notions: "truth," "metaphysical doubt," "(metaphysical) certainty," and "knowledge." Roughly speaking, a clear and distinct perception is a pure understanding, an intellectual perception, or a mental intuition in which a purified and attending mind has a simple mental intuition of a simple proposition or a necessary deduction (i.e., a complex mental intuition) from such simple propositions to a complex proposition. A simple proposition can be regarded as a necessary conjunction of simple ideas. Descartes' composition theory of ideas, which supposes that all ideas are composed of simple ideas, provides a crucial basis for clear and distinct perception. Descartes' doctrine of clear and distinct perception is an attempt at mathematizing epistemology and is the main content of his new "method" (for truth and knowledge), which he sought throughout his life. This book attempts to shape a new image of Descartes' epistemology.

According to a traditional picture, perception and belief have starkly different epistemic roles. Beliefs have epistemic statuses as justified or unjustified, depending on how they are formed and maintained. In contrast, perceptions are “unjustified justifiers.” Core cognition is a set of mental systems that stand at the border of perception and belief, and has been extensively studied in developmental psychology. Core cognition's borderline states do not fit neatly into the traditional epistemic picture. What is the epistemic role of these states? Focusing on the core object system, the author argues that core object representations have epistemic statuses like beliefs do, despite their many prototypically perceptual features. First, the author argues that it is a sufficient condition on a mental state's having an epistemic status as justified or unjustified that the state is based on reasons. Then the author argues that core object representations are based on reasons, through an examination of both experimental results and key markers of the basing relation. The scope of mental states that are subject to epistemic evaluation as justified or unjustified is not restricted to beliefs.

Intuition is sometimes derided as an abstruse or esoteric phenomenon akin to crystal-ball gazing. Such derision appears to be fuelled primarily by the suggestion, evidently endorsed by traditional rationalists such as Plato and Descartes, that intuition is a kind of direct, immediate apprehension akin to perception. This paper suggests that although the perceptual analogy has often been dismissed as encouraging a theoretically useless metaphor, a quasi-perceptualist view of intuition may enable rationalists to begin to meet the challenge of supplying a theoretically satisfying treatment of their favoured epistemic source. It is argued, first, that intuitions and perceptual experiences are at a certain level of abstraction the same type of mental state, presentations, which are distinct from beliefs, hunches, inclinations, attractions, and seemings. The notion of a presentation is given a positive explication, which identifies its characteristic features, accounts for several of its substantive psychological roles, and systematically locates it in a threefold division among types of contentful states. Subsequently, it is argued that presentations, intuitive no less than sensory, are by their nature poised to play a distinctive epistemic role. Specifically, in the case of intuition, we encounter an intellectual state that is so structured as to provide justification without requiring justification in turn—something which may, thus, be thought of as ‘given’

The self, Joseph LeDoux tells us, is “the totality of the living organism”. Most disciplines in the natural sciences focus on only one or two levels of organization. Indeed, Dmitri Mendeleev figured out the periodic table of the elements without knowing any of the underlying quantum mechanics or stereochemistry. There are, however, at least a dozen levels of organization within the neurosciences — and, if we use a metaphor, we temporarily create yet another. This leads to considerable confusion and arguments at cross purposes over whether learning is an alteration at the level of gene expression, ion channels, synapses, neurons or circuits. Each neuron has thousands of synapses, which produce currents that summate to form an impulse train. But only rarely is the activity of a single neuron sufficient to cause a perception or trigger an action. Neurons usually act as members of ‘committees’ — what Donald Hebb in 1949 called cellassemblies. Just as in academia, one individual may function in different committees on different occasions. A concept, including any explicit memory that we can talk about, is probably formed by such a committee. Implicit memories are less differentiated — they are part of the ‘feltwork’, together with motivations and emotions, that biases the choice of one’s next act. In this well-written 400-page appreciation of behavioural neuroscience, LeDoux argues that synapses are the seat of self. He says, in effect, that you are your memories; that it is the uniqueness of an array of synaptic strengths that distinguishes one twin from another. Fair enough, but why not instead focus on one’s unique array of ion channels? Or neurons, because a neuron is the closest thing we have to a computational unit? Or one’s unique arrangement of those overlapping, redundant hebbian committees? None of these make for a catchy book title, but relating other things to the synapses proves to be a good way of covering a lot of fascinating material at the overlying levels, including a few updates to LeDoux’s earlier book The Emotional Brain.

ABSTRACT E. M. Curley has said that Descartes’ cogito, ergo sum “is as obscure on examination as it is compelling at first glance.” Why should that be? Maybe because the cogito raises so many textual and interpretive questions. Is it an argument or an intuition? If it is an argument, does it require an additional premise? Is it best interpreted as a “performance?” Is it best seen as the discovery that any reason proposed for doubting its success entails the meditator’s existence? And so on. But all these questions typically arise in the wake of worries about the cogency of the cogito when it is treated as an argument and worded in its canonical form, “I think, therefore I exist.” In this essay, I focus on what I take to be the most fundamental reason for questioning the cogito’s cogency when it is so treated—namely that the “I” in its premise is question-begging. I distinguish that reason from other reasons that are sometimes conflated with it, and I argue that it is not a good reason. I then comment on some of the questions mentioned above in light of my defense of the cogito seen in that traditional way.

This volume features new perspectives on the implications of cross-linguistic and cultural diversity for epistemology. It brings together philosophers, linguists, and scholars working on knowledge traditions to advance work in epistemology that moves beyond the Anglophone sphere. The first group of chapters provide evidence of cross-linguistic or cultural diversity relevant to epistemology and discuss its possible implications. These essays defend epistemic pluralism based on Sanskrit data as a commitment to pluralism about epistemic stances, analyze the use of two Japanese knowledge verbs in relation to knowledge how, explore the Confucian notion of justification, and surveys cultural differences about the testimonial knowledge. The second group of chapters defends "core monism"--which claims that despite the cross-linguistic diversity of knowledge verbs, there is certain core epistemological meaning shared by all languages--from both a Natural Semantic Metalanguage and skeptical perspective. The third cluster of essays considers the implications of cultural diversity for epistemology based on anthropological studies. These chapters explore real disparities in folk epistemology across cultures. Finally, the last two chapters discuss methods or perspectives to unify epistemology despite and based on the diversity of folk intuitions and epistemological concepts. Ethno-Epistemology is an essential resource for philosophers working in epistemology and comparative philosophy, as well as linguists and cultural anthropologists interested in the cultural-linguistic diversity of knowledge traditions.

Descartes's general rule that “whatever is clearly and distinctly perceived is true” has traditionally been criticized on two closely related grounds. As Leibniz, for example, puts it, clearness and distinctness are of no value as criteria of truth unless we have criteria of clearness and distinctness; but Descartes gives none. And consequently, the standards of judgment which the rule in fact evokes are purely subjective and psychological. There must hence be set up analytic, logical “marks” by means of which it can infallibly and without arbitrariness be recognized whether any ideas or propositions are or are not clear and distinct.

Abstract. As a general theory of reasoning—and as a general theory of what holds true under every possible circumstance—logic is supposed to be ontologically neutral. It ought to have nothing to do with questions concerning what there is, or whether there is anything at all. It is for this reason that traditional Aristotelian logic, with its tacit existential presuppositions, was eventually deemed inadequate as a canon of pure logic. And it is for this reason that modern quantification theory, too, with its residue of existentially loaded theorems and patterns of inference, has been claimed to suffer from a defect of logical purity. The law of non-contradiction rules out certain circumstances as impossible—circumstances in which a statement is both true and false, or perhaps circumstances where something both is and is not the case. Is this to be regarded as a further ontological bias?

The purpose of this paper is threefold: First, I provide a framework – based on Sellars’ distinction between the manifest and the scientific image – for illuminating the distinction between liberal and ‘orthodox’ scientific naturalism. Second, I level a series of objections against expanded liberal naturalism and its core commitment to the autonomy of manifest-image explanations. Further, I present a view which combines liberal and scientific naturalism, albeit construed in resolutely non-representationalist terms. Finally, I attempt to distinguish my own (Sellars- and Peirce-inspired) position from the very similar pragmatic liberal naturalist view, that of Huw Price. I do this by suggesting that a ‘monistic’ Peircian evolutionary naturalism which accepts the Sellarsian scientia mensura principle not only is consistent with ungrudging recognition of the irreducibility of normative facts and the plurality of our discursive practices, but also shows how this irreducibility, by being understood in terms of an evolution-by-selection of a population of perceptual-practical-inferential habits, can be at the same time considered as naturalistically explicable – without any appeal to an expanded manifest-image conception of nature.

Aristotelian metaphysics is currently undergoing something of a renaissance. This volume brings together fourteen essays from leading philosophers who are sympathetic to this conception of metaphysics, which takes its cue from the idea that metaphysics is the first philosophy. The primary input from Aristotle is methodological, but many themes familiar from his metaphysics will be discussed, including ontological categories, the role and interpretation of the existential quantifier, essence, substance, natural kinds, powers, potential, and the development of life. The volume mounts a strong challenge to the type of ontological deflationism which has recently gained a strong foothold in analytic metaphysics. It will be a useful resource for scholars and advanced students who are interested in the foundations and development of philosophy.

Van Fraassen’s (1989) infamous best of a bad lot objection is widely taken to be the most serious problem that afflicts theories of inference to the best explanation (IBE), for it alleges to show that we should not accept the conclusion of any case of such reasoning as it actually proceeds. Moreover, this is supposed to be the case irrespective of the details of the particular criteria used to select best explanations. The best of a bad lot objection is predicated on, and really only requires, the idea that in any real case of IBE where one hypothesis is favored as best over those with which it competes, it is always the case that it is more likely that the true explanation is to be found in the set of unformulated and unconsidered logical alternatives to the set of actually considered hypotheses. On this basis, Van Fraassen believes that accepting the conclusion of IBEs so understood is irrational and this is simply because such inferences are supposedly not probative. In this paper the best of a bad lot objection will be addressed and it will be shown that Van Fraassen’s notorious criticism of IBE depends on a problematic conflation of two notions of rationality and thus that his criticism of IBE involves a damning equivocation. In essence, he conflates ideal standards of rationality with epistemic standards of rationality and, in so doing, makes it appear to be the case that we should not accept the conclusions of IBEs. But, when we disambiguate the concepts of rationality at work in the argument Van Fraassen’s conclusion simply does not follow.

In this paper, I will argue that metaphysicians ought to utilize quantum theories of gravity as incubators for a future metaphysics. I will argue why this ought to be done and will present cases studies from the history of science where physical theories have challenged both the dogmatic and speculative metaphysician. I provide two theories of QG and demonstrate the challenge they pose to certain aspects of our current metaphysics; in particular, how they challenge our understanding of the abstract–concrete distinction. I demonstrate how five different accounts of the distinction each fail to hold under the received interpretations of loop quantum gravity and string theory. The central goal of this paper is to encourage metaphysicians to look to physical theories, especially those involving cosmology such as string theory and loop quantum gravity, when doing metaphysics.

It is a common view among philosophers of science that theoretical virtues (also known as epistemic or cognitive values), such as simplicity and consistency, play an important role in scientific practice. In this article, I set out to study the role that theoretical virtues play in scientific practice empirically. I apply the methods of data science, such as text mining and corpus analysis, to study large corpora of scientific texts in order to uncover patterns of usage. These patterns of usage, in turn, might shed some light on the role that theoretical virtues play in scientific practice. Overall, the results of this empirical study suggest that scientists invoke theoretical virtues explicitly, albeit rather infrequently, when they talk about models (less than 30%), theories (less than 20%), and hypotheses (less than 15%) in their published works. To the extent that they are mentioned in scientific publications, the results of this study suggest that accuracy, consistency, and simplicity are the theoretical virtues that scientists invoke more frequently than the other theoretical virtues tested in this study. Interestingly, however, depending on whether they talk about hypotheses, theories, or models, scientists may invoke one of those theoretical virtues more than the others.

We evaluate a growing trend towards anti-representationalism in cognitive science in the context of recent research into the development and maintenance of anorexia nervosa in cognitive neuropsychiatry. We argue two things: first, that this research relies on an explanatorily robust concept of representation—the concept of a long-term body schema; second, that this body representation underlies our most basic environmental interactions and affordance perception—the psychological phenomena supposed to be most hospitable to a non-representationalist treatment.

Clark has recently suggested that predictive processing advances a theory of neural function with the resources to put an ecumenical end to the “representation wars” of recent cognitive science. In this paper I defend and develop this suggestion. First, I broaden the representation wars to include three foundational challenges to representational cognitive science. Second, I articulate three features of predictive processing’s account of internal representation that distinguish it from more orthodox representationalist frameworks. Specifically, I argue that it posits a resemblance-based representational architecture with organism-relative contents that functions in the service of pragmatic success, not veridical representation. Finally, I argue that internal representation so understood is either impervious to the three anti-representationalist challenges I outline or can actively embrace them.

It is sometimes supposed that, in principle, we cannot offer an explanation for why there is something rather than nothing. I argue that this supposition is a mistake, and stems from a needlessly myopic conception of the form explanations can legitimately take. After making this more general point, I proceed to offer a speculative suggestion regarding one sort of explanation which can in principle serve as an answer to the question “why is there something rather than nothing?” The suggestion is that there may be something rather than nothing in virtue of the truth of certain sorts of subjunctive conditionals.