One of Hume's most well-known works and a masterpiece of philosophy, A Treatise of Human Nature is indubitably worth taking the time to read.

This book is an important contribution to the contemporary epistemological literature. It is the only available book-length treatment of epistemological issues associated with the a priori. Moreover, it provides the most comprehensive articulation and defense of traditional rationalism. The book is tightly organized, crisply argued, and sets the standard against which competing accounts must be measured.

The central recommendation of this article is that philosophers trained in the analytic tradition ought to add the sensibilities and skills of the historian to their methodological toolkit. The value of an historical approach to strictly philosophical matters is illustrated by a case study focussing on the medieval origin of conceivability arguments and contemporary views of modality. It is shown that common metaphilosophical views about the nature of the philosophical enterprise as well as certain inference patterns found in thinkers from (...) Descartes to Chalmers have their origin in the theological concerns of the Scholastics. Since these assumptions and inference patterns are difficult to motivate when shorn of their original theological context, the upshot is that much post-Cartesian philosophy is cast in an altogether unfamiliar, and probably unwelcome, light. The methodological point, however, is that this philosophical gain is born of acquaintance with the history of ideas. (shrink)

A comprehensive defence of the rationalist view that insight independent of experience is a genuine basis for knowledge.

Descartes propounded the allegedly "strange", "peculiar", "curious" and "incoherent" doctrine that necessary truths are made true by God's voluntary act. It is generally held that this doctrine must be kept out of sight while other Cartesian topics are being discussed. This paper offers an interpretation of this Cartesian doctrine under which it comes out as reasonable, consistent with the rest of his philosophy, and possible even true. According to this interpretation--which is more respectful of and close to Descartes's text than (...) is the customary one--Descartes equated the alethic modalities with facts about human intellectual limitations, somewhat in the manner of Wittgenstein. Thus, God created modalities creating humans in the way he did. (shrink)

The infinitesimal methods commonly used in the 17th and 18th centuries to solve analytical problems had a great deal of elegance and intuitive appeal. But the notion of infinitesimal itself was flawed by contradictions. These arose as a result of attempting to representchange in terms ofstatic conceptions. Now, one may regard infinitesimals as the residual traces of change after the process of change has been terminated. The difficulty was that these residual traces could not logically coexist with the static quantities (...) traditionally employed by mathematics. The solution to this difficulty, as it turns out, is to regard these quantities asalso being subject to (a form of) change, for then they will have the same nature as the infinitesimals representing the residual traces of change, and will become,ipso facto, compatible with these latter.In fact, the category-theoretic models which realize the Principle of Infinitesimal Linearity may themselves be regarded as representations of a general concept of variation (cf. Bell (1986)). While the static set-theoretical models represent change or motion by making a detour through the actual (but static) infinite, the varying category-theoretic models enable such change to be representeddirectly, thus permitting the introduction of geometric infinitesimals and, as we have attempted to demonstrate in this paper, the virtually complete incorporation of the methods of the early calculus.It is surely a remarkable — even an ironic — fact that the contradiction between the flux of the objective world and the stasis of mathematical entities has found its resolution in category theory, a branch of mathematics commonly, and, as one now sees, mistakenly, regarded as the summit of gratuitous abstraction. (shrink)

The paper begins with a clarification of the notions of intuition (and, in particular, modal intuition), modal error, conceivability, metaphysical possibility, and epistemic possibility. It is argued that two-dimensionalism is the wrong framework for modal epistemology and that a certain nonreductionist approach to the theory of concepts and propositions is required instead. Finally, there is an examination of moderate rationalism’s impact on modal arguments in the philosophy of mind -- for example, Yablo’s disembodiment argument and Chalmers’s zombie argument. A less (...) vulnerable style of modal argument is defended, which nevertheless wins the same anti-materialist conclusions sought by these other arguments. (shrink)

This chapter contains section titled: Acknowledgments References and Further Reading.

This book is a defense of modal realism; the thesis that our world is but one of a plurality of worlds, and that the individuals that inhabit our world are only a few out of all the inhabitants of all the worlds. Lewis argues that the philosophical utility of modal realism is a good reason for believing that it is true.

This paper examines Descartes' controversial theory of the creation of eternal truths and the views of modality attributed to Descartes in recent interpretations of it. It shows why attempts to make Descartes' view intelligible by distinctions of different kinds of modality fail to do justice to his theory, which is radical indeed without being incoherent or involving universal possibilism or irrationalism. Descartes' opposition to traditional rationalist views of modality, it suggests, can be seen instead as foreshadowing contemporary views prefixed, logical (...) structure of reality or of the divine intellect. (shrink)

" Il est à remarquer en tout ce que j'écris que je ne suis pas l'ordre des matières mais seulement celui des raisons, c'est-à-dire que je n'entreprends point de dire en un même lieu tout ce qui appartient à une matière, à cause qu'il me serait impossible de la bien prouver y ayant des raisons qui doivent être tirées de bien plus loin les unes que les autres, mais en raisonnant par ordre, a facilioribus ad difficiliora, j'en déduis ce que (...) je puis, tantôt pour une matière, tantôt pour une autre, ce qui est à mon avis le vrai chemin pour bien trouver et expliquer la vérité. " (Descartes à Mersenne, 24 décembre 1640). " Si l'ordre analytique est le seul à procurer la démonstration valable de la philosophie, si les Méditations qui se développent rigoureusement selon cet ordre, permettent seules de comprendre à coup sûr l'ensemble de la doctrine, il n'y a pas d'autre méthode pour comprendre les Méditations elles-mêmes que de mettre en évidence cet ordre par lequel seul elles démontrent leur vérité. " (Martial Gueroult). (shrink)

Modal propositional logic; Modal predicate logic; A survey of modal logic.

….it [is] wholly irrational to regard as doubtful matters that are perceived clearly and distinctly by the understanding in its purity, on account of mere prejudices of the senses and hypotheses in which there is an element of the unknown.Descartes, Geometrical Exposition of the MeditationsSubstance dualism, once a main preoccupation of Western metaphysics, has fallen strangely out of view; today’s mental/physical dualisms are dualisms of fact, property, or event. So if someone claims to find a difference between minds and bodies (...) per se, it is not initially clear what he is maintaining. Maybe this is because one no longer recognizes ‘minds’ as entities in their own right, or ‘substances.’ However, selves - the things we refer to by use of ‘I’ - are surely substances, and it does little violence to the intention behind mind/body dualism to interpret it as a dualism of bodies and selves. If the substance dualist’s meaning remains obscure, that is because it can mean several different things to say that selves are not bodies. (shrink)

….it [is] wholly irrational to regard as doubtful matters that are perceived clearly and distinctly by the understanding in its purity, on account of mere prejudices of the senses and hypotheses in which there is an element of the unknown.Descartes, Geometrical Exposition of the MeditationsSubstance dualism, once a main preoccupation of Western metaphysics, has fallen strangely out of view; today’s mental/physical dualisms are dualisms of fact, property, or event. So if someone claims to find a difference between minds and bodies (...) per se, it is not initially clear what he is maintaining. Maybe this is because one no longer recognizes ‘minds’ as entities in their own right, or ‘substances.’ However, selves - the things we refer to by use of ‘I’ - are surely substances, and it does little violence to the intention behind mind/body dualism to interpret it as a dualism of bodies and selves. If the substance dualist’s meaning remains obscure, that is because it can mean several different things to say that selves are not bodies. (shrink)

Any property has two sorts of causal features: “forward-looking” ones, having to do with what its instantiation can contribute to causing, and ldquo;backward-looking” ones, having to do with how its instantiation can be caused. Such features of a property are essential to it, and properties sharing all of their causal features are identical. Causal necessity is thus a special case of metaphysical necessity. Appeals to imaginability have no more force against this view than they do against the Kripkean view that (...) statements like “Gold is an element” are metaphysically necessary. (shrink)

Any property has two sorts of causal features: “forward‐looking” ones, having to do with what its instantiation can contribute to causing, and ldquo;backward‐looking” ones, having to do with how its instantiation can be caused. Such features of a property are essential to it, and properties sharing all of their causal features are identical. Causal necessity is thus a special case of metaphysical necessity. Appeals to imaginability have no more force against this view than they do against the Kripkean view that (...) statements like “Gold is an element” are metaphysically necessary. (shrink)

The dogma that the propositional logic of metaphysical modality is S5 is rebutted. The author exposes fallacies in standard arguments supporting S5, arguing that propositional metaphysical modal logic is weaker even than both S4 and B, and is instead the minimal and weak metaphysical-modal logic T.

This paper defends an interpretation of Descartes according to which he sees us as having normative (and not merely psychological) certainty of all clear and distinct ideas during the period in which they are apprehended clearly and distinctly. However, on this view, a retrospective doubt about clear and distinct ideas is possible. This interpretation allows Descartes to avoid the Cartesian Circle in an effective way and also shows that Descartes is surprisingly, in some respects, an epistemological externalist. The paper goes (...) on to defend this interpretation against some powerful philosophical objections by Margaret Wilson and others by showing how Descartes' doctrine of the creation of the eternal truths can be brought in to support his epistemology. This doctrine and other analogous positions in Descartes can also reveal that Descartes, again surprisingly, takes important steps toward doing epistemology without direct appeal to God and God's veracity. (shrink)

Sets of contingent objects, perhaps, are as contingent as their members; but properties, propositions, numbers and states of affairs, it seems, are objects whose non-existence is quite impossible. If so, however, how are they related to God? Suppose God has a nature: a property he has essentially that includes each property essential to him. Does God have a nature? And if he does, is there a conflict between God's sovereignty and his having a nature? How is God related to such (...) abstract objects as properties and propositions? These are the questions I want to explore. - Introduction. (shrink)

This is about Gassendi's 5th Objections to the Meditations and Descartes' Reply. The main issue is what clear and distinct perception consists in and whether we need a criterion in order to know if we perceive something clearly and distinctly.

It is fortunate for my purposes that English has the two words ‘almighty’ and ‘omnipotent’, and that apart from any stipulation by me the words have rather different associations and suggestions. ‘Almighty’ is the familiar word that comes in the creeds of the Church; ‘omnipotent’ is at home rather in formal theological discussions and controversies, e.g. about miracles and about the problem of evil. ‘Almighty’ derives by way of Latin ‘omnipotens’ from the Greek word ‘ pantokratōr ’; and both this (...) Greek word, like the more classical ‘ pankratēs ’, and ‘almighty’ itself suggest God's having power over all things. On the other hand the English word ‘omnipotent’ would ordinarily be taken to imply ability to do everything; the Latin word ‘omnipotens’ also predominantly has this meaning in Scholastic writers, even though in origin it is a Latinization of ‘ pantocratōr ’. So there already is a tendency to distinguish the two words; and in this paper I shall make the distinction a strict one. I shall use the word ‘almighty’ to express God's power over all things, and I shall take ‘omnipotence’ to mean ability to do everything. (shrink)

It is fortunate for my purposes that English has the two words ‘almighty’ and ‘omnipotent’, and that apart from any stipulation by me the words have rather different associations and suggestions. ‘Almighty’ is the familiar word that comes in the creeds of the Church; ‘omnipotent’ is at home rather in formal theological discussions and controversies, e.g. about miracles and about the problem of evil. ‘Almighty’ derives by way of Latin ‘omnipotens’ from the Greek word ‘pantokratōr’; and both this Greek word, (...) like the more classical ‘pankratēs’, and ‘almighty’ itself suggest God's having power over all things. On the other hand the English word ‘omnipotent’ would ordinarily be taken to imply ability to do everything; the Latin word ‘omnipotens’ also predominantly has this meaning in Scholastic writers, even though in origin it is a Latinization of ‘pantocratōr’. So there already is a tendency to distinguish the two words; and in this paper I shall make the distinction a strict one. I shall use the word ‘almighty’ to express God's power over all things, and I shall take ‘omnipotence’ to mean ability to do everything. (shrink)

The book is an extended study of the problem of consciousness. After setting up the problem, I argue that reductive explanation of consciousness is impossible , and that if one takes consciousness seriously, one has to go beyond a strict materialist framework. In the second half of the book, I move toward a positive theory of consciousness with fundamental laws linking the physical and the experiential in a systematic way. Finally, I use the ideas and arguments developed earlier to defend (...) a form of strong artificial intelligence and to analyze some problems in the foundations of quantum mechanics. (shrink)

It hath been an old remark, that Geometry is an excellent Logic.