This paper investigates Hume's theory of the perception of spatial magnitude or size as developed in the _Treatise<D>, as well as its relation to his concepts of space and geometry. The central focus of the discussion is Hume's espousal of the 'composite' hypothesis, which holds that perceptions of spatial magnitude are composed of indivisible sensible points, such that the total magnitude of a visible figure is a derived by-product of its component parts. Overall, it will be argued that a straightforward (...) reading of this hypothesis fails to do full justice to the complexity of Hume's theory of spatial perception and geometry, and that a more adequate treatment must also admit an important role for the more direct process of spatial magnitude perception which he dubs 'intuition'. (shrink)

In this paper we consider a puzzle concerning Hume's account of time and what he calls “steadfast unchanging objects”—that is, unchanging objects coexisting with temporal successions. On the one hand, Hume maintains that steadfast unchanging objects are temporally indivisible. On the other, he allows that such unchanging objects are capable of undergoing a determinate number of alterations in a given length of time, which seems to imply that they are at least potentially temporally divisible. After arguing that Donald Baxter's influential (...) interpretation of Hume's theory of time cannot resolve this tension, we propose that Hume offers a skeptical resolution of the difficulty. (shrink)

Hume’s discussion of space, time, and mathematics at T 1.2 appeared to many earlier commentators as one of the weakest parts of his philosophy. From the point of view of pure mathematics, for example, Hume’s assumptions about the infinite may appear as crude misunderstandings of the continuum and infinite divisibility. I shall argue, on the contrary, that Hume’s views on this topic are deeply connected with his radically empiricist reliance on phenomenologically given sensory images. He insightfully shows that, working within (...) this epistemological model, we cannot attain complete certainty about the continuum but only at most about discrete quantity. Geometry, in contrast to arithmetic, cannot be a fully exact science. A number of more recent commentators have offered sympathetic interpretations of Hume’s discussion aiming to correct the older tendency to dismiss this part of the Treatise as weak and confused. Most of these commentators interpret Hume as anticipating the contemporary idea of a finite or discrete geometry. They view Hume’s conception that space is composed of simple indivisible minima as a forerunner of the conception that space is a discretely (rather than continuously) ordered set. This approach, in my view, is helpful as far as it goes, but there are several important features of Hume’s discussion that are not sufficiently appreciated. I go beyond these recent commentators by emphasizing three of Hume’s most original contributions. First, Hume’s epistemological model invokes the “confounding” of indivisible minima to explain the appearance of spatial continuity. Second, Hume’s sharp contrast between the perfect exactitude of arithmetic and the irremediable inexactitude of geometry reverses the more familiar conception of the early modern tradition in pure mathematics, according to which geometry (the science of continuous quantity) has its own standard of equality that is independent from and more exact than any corresponding standard supplied by algebra and arithmetic (the sciences of discrete quantity). Third, Hume has a developed explanation of how geometry (traditional Euclidean geometry) is nonetheless possible as an axiomatic demonstrative science possessing considerably more exactitude and certainty that the “loose judgements” of the vulgar. (shrink)

Eric Watkins has argued on philosophical, textual, and historical grounds that Kant’s account of causation in the first Critique should not be read as an attempt to refute Hume’s account of causation. In this paper, I challenge the arguments for Watkins’ claim. Specifically, I argue (1) that Kant’s philosophical commitments, even on Watkins’ reading, are not obvious obstacles to refuting Hume, (2) that textual evidence from the “Disciple of Pure Reason” suggests Kant conceived of his account of causation as such (...) a refutation, and (3) that none of Hume’s early German critics provided responses to this account that would have satisfied Kant. Watkins’ reading of Kant’s account of causation is thus more compatible with traditional views about Kant’s relationship to Hume than Watkins believes. (shrink)

This paper considers whether elements of T 1.2 Of the Ideas of Space and Time in Hume’s Treatise is inconsistent with skepticism regarding the external world in T 1.4.2 Of Scepticism with regard to the Senses. This apparent tension vexes commentators, and efforts to resolve it drives the recent scholarship on this section of Hume’s Treatise. To highlight this tension I juxtapose Hume’s “Adequacy Principle” with what I call his “skeptical causal argument” in T 1.4.2. The Adequacy Principle appears to (...) state that we can form conclusions about objects through the comparison of our ideas of them, while Hume’s skeptical causal argument asserts that we cannot form any conclusions about objects using ideas. Is Hume being inconsistent? I argue that he is not. My paper has three parts. First, I give a general reading of the Adequacy Principle in light of Hume’s peculiar claim that it is “the foundation of all human knowledge.” I then explain why the Adequacy Principle itself is not inconsistent with Hume’s skeptical causal argument by explaining how the term “object” should not be strictly read as “external” object but merely the “the object of inquiry” or even “the matter under consideration.” Second, I sketch Hume’s employment of the Adequacy Principle in his Divisibility Argument, explaining how this is also not at odds with his skeptical causal argument. In the third and final part I explore various interpretations in the literature and consider whether “finite extensions” need necessarily be read as external objects. (shrink)

In the Treatise of Human Nature, David Hume mounts a spirited assault on the doctrine of the infinite divisibility of extension, and he defends in its place the contrary claim that extension is everywhere only finitely divisible. Despite this major departure from the more conventional conceptions of space embodied in traditional geometry, Hume does not endorse any radical reform of geometry. Instead Hume espouses a more conservative approach, claiming that geometry fails only “in this single point” – in its purported (...) proofs of infinite divisibility – while “all of its other arguments” remain intact. -/- In this paper, after laying out the prima facie case for Hume’s radical challenge to traditional geometry, I consider five strategies for blocking the arguments for infinite divisibility while conserving most of geometry. I show that each of these interpretive strategies suffers from serious substantive problems, and so none of them delivers an interpretation of Hume’s account that provides him with a way of blocking the geometric arguments for infinite divisibility while sustaining his geometric conservatism. (shrink)