Online research in philosophy

A major source of latter-day skepticism about necessity is the work of David Hume. Hume is widely taken to have endorsed the Humean claim : there are no necessary connections between distinct existences. The Humean claim is defended on the grounds that necessary connections between wholly distinct things would be mysterious and inexplicable. Philosophers deploy this claim in the service of a wide variety of philosophical projects. But Saul Kripke has argued that it is false. According to Kripke, there are necessary connections between distinct existences; in particular, there are necessary connections between material objects and their material origins. This essay argues that the primary motivation for the Humean claim, Hume's datum , also motivates the key premise in an argument for the necessity of origins. The very considerations that the Humean takes to show that necessary connections between wholly distinct things would be mysterious and inexplicable indicate that there must be some such necessary connections. Thus, in the absence of alternative support, there is no reason to believe the Humean claim.

This paper sets up and then solves a puzzle for the sceptical realist interpretation of Hume. The puzzle takes off when the sceptical realist attributes to Hume the following metaphysical theses:

(NH1) Causal powers grounding necessary connections in nature exist. (NH2) Causal powers grounding necessary connections in nature are what make things happen.

It then attributes an epistemological thesis to him:

(NH3) We have no knowledge of causal powers in nature nor of the necessary connections in nature which these powers ground.

But putting these three theses together seems to yield a problematic result. The epistemological thesis seems to have two corollaries as its upshot.

(C1) We cannot know that causal powers grounding necessary connections in nature exist.

(C2) We cannot know that causal powers grounding necessary connections in nature are what make things happen.

That is, we cannot know (NH1) and (NH2). New Hume’s position, the sceptical realist interpretation, seems to make Hume out to be arguing for a view that is self-undermining or dialectically unstable by his own empiricist lights. I argue that there is an overlooked externalist dimension to Hume’s epistemology and draw on this to solve the puzzle.

It has often been suggested (1) that according to Hume it is impossible in principle for testimony to prove a miracle, and (2) that an indispensable element in Hume's argument is the claim that a miracle is by definition a violation of the laws of nature. I argue that both (1) and (2) are mistaken, and that, once Hume's 'Of Miracles' is viewed in a proper historical context, it emerges that Hume's argument against miracles is considerably different from what is usually supposed.

This paper contends that the first argument of Hume's "Of scepticism with regard to reason" entails that humans have no knowledge as Hume understands knowledge. In defending this claim, we also see how Hume's argument anticipates an important aspect of an extremely influential 20th century development: the collapse of the analytic/synthetic distinction.

'There is nothing either good or bad, but thinking makes it so.'l But if things considered in themselves are neither good nor bad, if there is no realm of value existing independently of animate beings and their activities, then thought is not the activity that summons value into being. Hume reminds us, 'Reason is, and ought only to be the slave of the passions', and while Hume's dictum has been widely disputed, we shall defend it.2 Desire, not thought, and volition, not 'cognition, are the springs of good and evil.

Why believe Hume's Dictum, according to which there are, roughly speaking, no necessary connections between wholly distinct entities? Schaffer ('Quiddistic Knowledge', 2009) suggests that HD, at least as applied to causal or nomological connections, is motivated as required by the best account of (the truth) of counterfactuals---namely, a similarity-based possible worlds account, where the operative notion of similarity requires 'miracles'---more specifically, worlds where entities of the same type that actually exist enter into different laws. The main cited motivations for such an account of similarity are first, that some salient contexts presuppose CF asymmetry, and second, that accounts of CFs failing to presuppose CF asymmetry are epistemologically problematic, such that under conditions of determinism, the variations in initial micro-conditions needed to implement a given counterfactual antecedent would result in so many changes to macro-states that evaluation of CFs would be rendered practically impossible. Against the first reason, I argue that no non-artificial contexts presuppose CF asymmetry; against the second, I observe that such micro-variation is compatible, in principle, with significant similarity as regards macroscopic states of affairs---enough, in particular, to allow CFs to be appropriately evaluated.

Humeans and non-Humeans reasonably agree that there may be necessary connections between entities that are identical or merely partly distinct—between, e.g., sets and their individual members, fusions and their individual parts, instances of determinates and determinables, members of certain natural kinds and certain of their intrinsic properties, and (especially among physicalists) certain physical and mental states. Humeans maintain, however, that as per “Hume’s Dictum”, there are no necessary connections between entities that are wholly distinct;1 and in particular, no necessary causal connections between such entities (even when the background conditions requisite for causation are in place). The Humean’s differential treatment appears principled, in reflecting that commonly accepted necessary connections involve constitutional relations, whereas wholly distinct entities (notably, causes and effects) do not constitute each other. I’ll argue, however, that the appearance of principle is not genuine, as per the following conditional: Constitutional→Causal: If one accepts certain constitutional necessities, one should accept certain causal necessities. This result provides needed leverage in assessing the two main frameworks in the metaphysics of science, treating natural kinds, causes, laws of nature, and the like. These frameworks differ primarily on whether Hume’s Dictum is taken as a working constraint on theorizing; and it has proved difficult for either side to criticize the other without presupposing their preferred stance on the dictum, hence talking past one another. The arguments for Constitutional→Causal are based, however, in general and independent considerations about what facts in the world might plausibly warrant our beliefs in certain constitutional necessities involving broadly scientific entities. The Humean can respond to these arguments, which reveal a deep tension in their view, at attendant costs of implausibilty and adhocery. The non-Humean framework doesn’t face any such tension between constitutional and causal necessities, however, and so in this respect comes out ahead.

1.Puzzle According to a standard view in contemporary metaphysics, there are no necessary connections between distinct properties. But according to a standard view in philosophy of mind there are necessary connections between distinct properties. In short, we have a puzzle: standard metaphysics inconsistent with standard philosophy of mind. By ‘a standard view in contemporary metaphysics’ I mean, of course, Hume’s dictum that there are no necessary connections between distinct existences. I don’t mean the historical Hume; whether the historical Hume held Hume’s dictum I am sure is a controversial issue, and will not concern us. What will concern us rather is the idea that contemporary metaphysicians such as David Lewis and David Armstrong discuss and attribute to Hume (see, e.g., Lewis 1986 and Armstrong 1997). Of course Hume’s dictum does not say anything explicitly about properties; it talks of existences rather than properties. But ‘existences’ I take it, means ‘things that exist’ and, if we set nominalism aside—as I will do here—properties are things that exist. Hence the Humean dictum entails as a special case that there are no necessary connections between distinct properties.

We can modify Hume’s Principle in the same manner that George Boolos suggested for modifying Frege’s Basic Law V. This leads to the principle Small Hume. Then, we can show that Small Hume is interderivable with Hume’s Principle.