This thesis focuses on two related though different topics: first, the metaphysics of dispositions; second, the relation between dispositionalism and time. For this reason, the thesis is divided in two main parts: the first part concerns the first topic, and the second part concerns the second. The aim of the project is to argue that dispositionalism faces two different problems: first, there is no viable metaphysics for dispositional properties; second, there is no viable theory of time that can fit in a dispositional framework.

The first part of our thesis will explore the nature and history of the development of Hegel’s reconciliatory self-determining philosophical science, by demonstrating how Hegel radicalises and reformulates the essence of skepticism as the principle of determinate negation. We will attempt to elucidate precisely why the persistence of external skepticism represents nothing more for Hegel than abstract dogmatism and philosophical naivety. In the second part of our thesis we will concentrate upon early 19th century post-Hegelian skeptical responses to Hegel’s speculative idealism. We will argue that Schelling, Feuerbach and Kierkegaard all attempt to disrupt what they see as the oppressive self-satisfaction of Speculative Reason by elaborating a skeptical attack upon Hegelianism in the name of the particular. Each thinker attempts to articulate a skeptical opposition to what they respectively argue to be Hegel’s illegitimate effacement of the particular within the totality of speculative reason itself. They each seek to return to an irreducible point of entry take Hegel back with them, to take him back ‘outside’ of the system of reason and return him to the particular. We will begin by analysing Schelling’s attempts to confront Hegel with the ‘Real Being’ he accuses Hegel of effacing from the very beginning through the illegitimate identity of thought and being. We will then examine Feuerbach’s attempt to deconstruct Hegel’s dialectic of sense certainty in an effort to return Hegel to the irreducible sensory quality of Being. We conclude this part with an analysis of Kierkegaard’s arguments for what he understands as the ‘paradox’ of faith. We will show that Kierkegaard’s efforts are aimed at bringing Hegel into proximity with this paradoxical faith in order to demonstrate his failure to comprehend the true nature of faith. The skeptical attacks of all three thinkers will be rigorously examined in the light of Hegel’s understanding of the relationship between skepticism and philosophy that we will have outlined in the first part of our thesis. Our aim will be to show precisely how and why they ultimately fail to articulate a radically heterogeneous skeptical position with regard to Hegel’s speculative idealism. By demonstrating the precise nature of their failure we will set the scene for our discussion of Levinas’s skeptical relation to Hegel in the third part of this thesis. It will be our contention that Levinas successfully elaborates a response to Hegel’s speculative reason that clearly continues upon the trajectory initiated by the three 19* century post-Hegelian skeptics that we have examined, and that what ultimately marks his success in articulating a genuinely heterological thought will be the extent to which he precisely avoids the failures we have identified.

Philosophical discussion of the value of knowledge, inspired by Plato’s seminal discussion in the Meno, typically focuses on the question why it is better to know that p than to have a mere true belief that p. This question is notoriously difficult to answer in a satisfactory way. I argue that the difficulty we experience in trying to solve this problem is a symptom of the fact that we are approaching issues about the value of knowledge in the wrong way. Beneath the traditional problem there lurks a more fundamental issue about the aim of enquiry, namely, why should an enquirer who wants the truth about whether p aim to find out (i.e. acquire knowledge of) whether p, and not merely aim to arrive at a true belief about whether p? Identifying respects in which knowledge is superior to mere true belief is only one way of trying to answer this question, and, I argue, it is difficult to see how this approach to the question can succeed. An alternative is called for. Central to my alternative proposal is the idea that an enquirer will not have arrived at so much as a belief about whether p until he takes himself to have acquired knowledge of whether p. It is because this is so that an enquirer cannot make life easier for himself by merely aiming to arrive at true beliefs instead of knowledge. I justify this proposal by developing an account of belief according to which outright belief involves a disposition to judge that p, where judging that p is distinct from merely supposing that p for the sake of argument or guessing that p.

Hierarchies of evidence are an important and influential tool for appraising evidence in medicine. In recent years, hierarchies have been formally adopted by organizations including the Cochrane Collaboration [1], NICE [2,3], the WHO [4], the US Preventive Services Task Force [5], and the Australian NHMRC [6,7]. The development of such hierarchies has been regarded as a central part of Evidence-Based Medicine (e.g. [8-10]), a movement within healthcare which prioritises the use of epidemiological evidence such as that provided by Randomised Controlled Trials (RCTs). Philosophical work on the methodology of medicine has so far mostly focused on claims about the superiority of RCTs, and hence has largely neglected the questions of what hierarchies are, what assumptions they require, and how they affect clinical practice. This thesis shows that there is great variation in the hierarchies defended and in the interpretations they are, and can be, given. The interpretative assumptions made in using hierarchies are crucial to the content and defensibility of the underlying philosophical commitments concerning evidence and medical practice. Once this variation is been identified, it becomes clear that the little philosophical work that has been done so far affects only some hierarchies, under some interpretations. Modest interpretations offered by La Caze [11], conditional hierarchies like GRADE [12-14], and heuristic approaches such as that defended by Howick et al. [15,16] all survive previous philosophical criticism. This thesis extends previous criticisms by arguing that modest interpretations are so weak as to be unhelpful for clinical practice; that GRADE and similar conditional models omit clinically relevant information, such as information about variation in treatments’ effects and the causes of different responses to therapy; and that heuristic approaches lack the necessary empirical support. The conclusion is that hierarchies in general embed untenable philosophical assumptions: principally that information about average treatment effects backed by high-quality evidence can justify strong recommendations, and that the impact of evidence from individual studies can and should be appraised in isolation. Hierarchies are a poor basis for the application of evidence in clinical practice. The Evidence-Based Medicine movement should move beyond them and explore alternative tools for appraising the overall evidence for therapeutic claims.

The thesis is intended to contribute to the growing understanding of the indispensable role played by phenomenal consciousness in human cognition, and specifically in making our concepts of the external world available. The focus falls on so called observational concepts, a type of rudimentary, perceptually-based objective concepts in our repertoire — picking out manifest properties such as colors and shapes. A theory of such concepts gets provided, and, consequently, the exact role that perceptual consciousness plays in making concepts of this sort available gets settled. In the first half of the thesis, observational concepts get construed as a special type of recognitional concepts. On an analogy with perceptual demonstratives, having such concepts would involve having non-trivial knowledge of their reference. The experiential basis of such concepts would, among other things, provide for such constitutive knowledge. The theoretical background relevant to the hypothesis gets provided in the first chapter. A defence of the hypothesis follows in the second. In the second half of the thesis, care is taken to distinguish among two ways in which the constitutive knowledge of the reference of an observational concept could be fleshed out. In the third chapter, perceptual experience is shown to provide the basis both for knowledge of observational properties by acquaintance, and for knowledge of the essence of such properties — provided that knowledge of essence gets construed in the right, modest way. It might be natural to take knowledge by acquaintance to be the sort relevant to observational concept possession, especially given that in the case of perceptual demonstratives this is the role likely played by experience. However, this initial impression proves to be mistaken. The constitutive knowledge of the referent of an observational concept turns out to consist in the capacity to determine a priori the essence of the respective property. To show this, an argument gets provided in the penultimate fourth chapter, based on the key role played by experiences of instances of observational properties in optimal viewing conditions in enabling the possession of the respective observational concept.

In the thesis I explain why an immanent approach in philosophy means taking contingency to be "irreducible". I show why Deleuze and Guattari believe this to be the case and why they think Hegel fails to do this. I then go on to show in what way Hegel incorporates contingency into his system and how he also creates his own sense of "necessity" that emerges from the systematic treatment of contingent concepts. In this way I show how Hegel can respond to the demand for immanence made by Deleuze and Guattari. I suggest that freedom, for Hegel, consists in the systematic treatment of contingency in our lives and in our thinking.

The principal aim of this thesis is to mobilize the conceptual apparatus of the philosophy of Martin Heidegger in order to recuperate an understanding of life as it is concretely known and experienced in the immediacy of its actual being-lived-out, or simply, to develop a distinctly Heideggerian conception of primordial phenomenal life.

This thesis seeks to make a contribution to the history of modern continental philosophy by establishing a structural link between the thoughts of Friedrich Nietzsche and Maurice Merleau-Ponty. I argue that this link lies in the question of truth: both thinkers criticise the traditional concept of truth as objectivity. However, they both find in the existence of this very concept a problem that its rejection alone does not solve. What is it in our natural axistence that gave rise to the notion of truth? It is this questioning which I call the "question of truth". I locate three ways in which the question of truth informs Nietzsche and Merleau-Ponty's thoughts. Firstly, both thinkers propose a genealogy of the concept of "truth," one in which they suggest that our natural existence is structured in a pre-objective way: existing means making implicit truthclaims. Further, they each explain the appearance of our belief in truth in terms of a radicalisation of this implicit attribution of truth (Chapters I and IV). Secondly, both thinkers seek to recover the pre-objective ground from which truth as an erroneous concept arose. They propose strikingly similar methods to do so (Chapters II and V). This ground, once uncovered, must be examined. This investigation leads both Nietzsche and Merleau-Ponty to ontological considerations. They both ask how we must conceive of a Being whose structure allows for the existence of the belief in truth, or as I argue, error. As a conclusion, I suggest that both thinkers' investigations of the question of truth lead them to conceive of Being in a similar way, as the process of self-falsification by which indeterminate Being presents itself as determinate (Chapters III and VI).

This dissertation seeks to substantiate the thesis that Nietzsche's physiological thinking constitutes a radicalisation of Kantian critique. To this end it attempts to mark out some of the salient points of the latter project and to examine the ways in which it falls short of its own potential radicality. In chapters one and two the categories of relation - in which Kant articulates his theory of the temporal connection of phenomena explicitly - are traced through the Analytic and Dialectic of the Critique of Pure Reason and are read against the Deduction of the Pure Concepts of the Understanding which implicitly contains another theory of time. Since the Critique of the Teleological Faculty of Tudgerment complements Kant's theory of the temporal cohesion of phenomena, the third chapter offers a reading of it under the aspect of its relation to the wider project of critique. Chapter four draws together the multiple strands around which Kantian critique can be shown to mutate into Nietzsche's philosophical physiology and the theory of temporality implicit in it. Finally, Nietzschean physiology is presented in terms of his thinking of the becoming of matter, in terms of the will to power as eternal recurrence.

Heidegger perceives a naivety at the heart of Greek metaphysics to which he believes philosophy has remained prey throughout its history. This consists in having taken the understanding of being appropriate to the activity and experience of production [ποίησις] as the basis for understanding being in general. What such a interpretation lacks above all is a conception of human being as that which, distinct from the work, engages in productive activity. Only if such a conception were secured in contradistinction to the understanding of being derived from the work could, in Heidegger's view, ontology itself be placed on firm footing. By way of a response, Heidegger undertook a critical appropriation of Aristotle's practical philosophy and of the concept of πραξις in particular. This was to provide the basis of an account of Dasein. However, the outcome of the appropriation was problematic in two respects. First, Aristotle's own presentation of πραξις as the horizonal structure of teleological activity is dogged by incoherencies arising precisely from the influence exerted on the language of metaphysics by the experience of ποίησις. Indeed, the extent of this influence renders the language of metaphysics intrinsically ill-suited to the articulation of πραξις. Heidegger's appropriation of the figure of the end-in-itself must therefore be accompanied by an attempt to wrest it from the dominant conceptual structures of production. Second, insofar as the terms in which Heidegger couches the ontological determination of Dasein are taken from the language of practical philosophy, there arises a formal parallel between the transcendence of Dasein and possible structures of activity. Such a parallel invites the supposition that Dasein's transcendence may be enacted or accomplished in its comportment in and towards the world. Although I shall be concerned primarily with the first of these problems, the second remains a constant consideration and recurs explicitly at several junctures. Drawing on Heidegger's reading of Metaphysics Θ, I argue that he sought to secure an ontological interpretation of χίνησις, δύναμις and ένέργεια from which the influence of production had been displaced. Specifically, this hinges on the idea of finite appropriation as the essence of δύναμις. In addition, Heidegger emphasises the way in which each potentiality is related to the manner of its accomplishment. As an activity that is an end in itself, πραξις, is therefore understood as an activity of finite appropriation whose end is the very movement of appropriation itself. As such, it constitutes a repetition of the essence of δύναμις and of the transcendence of Dasein insofar as it is understood to be constituted by δύναμις.