The oldest solution to the circularity problem for Humeanism about the laws of nature

According to Humeanism about the laws, the laws of nature are nothing over and above certain kinds of regularities about particular facts (the “Humean mosaic”). Humeanism has often been accused of circularity: according to scientific practice laws often explain their instances, but on the Humean view they also reduce to the mosaic, which includes those instances. In this paper I formulate the circularity problem in a way that avoids a number of controversial assumptions routinely taken for granted in the literature, and against which many extant responses are therefore ineffective. I then propose a solution that denies the alleged Humean commitment that laws are explained by their instances. The solution satisfies three desiderata that other solutions don’t: it provides independent motivation against the idea that Humean laws are explained by their instances; it specifies the sense in which Humean laws are nonetheless “nothing over and above” their instances; and it gives an alternative account of what does explain the laws, if not their instances. This solution, I will argue, is not only the simplest but also the oldest one: it appeals only to tools and theses whose first appearance predates the earliest statements of the circularity problem itself.

     

There is no measurement problem for Humeans

The measurement problem concerns an apparent conflict between the two fundamental principles of quantum mechanics, namely the Schrödinger equation and the measurement postulate. These principles describe inconsistent behavior for quantum systems in so-called “measurement contexts.” Many theorists have thought that the measurement problem can only be resolved by proposing a mechanistic explanation of (genuine or apparent) wavefunction collapse that avoids explicit reference to “measurement.” However, I argue here that the measurement problem dissolves if we accept Humeanism about laws of nature. On a Humean metaphysics, there is no conflict between the two principles, nor is there any inherent problem with the concept of “measurement” figuring into the account of collapse.     

What the Humean Should Say About Entanglement

Tim Maudlin has influentially argued that Humeanism about laws of nature stands in conflict with quantum mechanics. Specifically Humeanism implies the principle Separability: the complete physical state of a world is determined by the intrinsic physical state of each space‐time point. Maudlin argues Separability is violated by the entangled states posited by QM. We argue that Maudlin only establishes that a stronger principle, which we call Strong Separability, is in tension with QM. Separability is not in tension with QM. Moreover, while the Humean requires Separability to capture the core tenets of her view, there's no Humean‐specific motivation for accepting Strong Separability. We go on to give a Humean account of entangled states which satisfies Separability. The core idea is that certain quantum states depend upon the Humean mosaic in much the same way as the laws do. In fact, we offer a variant of the Best System account on which the systemization procedure that generates the laws also serves to ground these states. We show how this account works by applying it to the example of Bohmian Mechanics. The 3N‐dimensional configuration space, the world particle in it and the wave function on it are part of the best system of the Humean mosaic, which consists of N particles moving in 3‐dimensional space. We argue that this account is superior to the Humean account of Bohmian Mechanics defended by Loewer and Albert, which takes the 3N‐dimensional space, and its inhabitants, as fundamental.     

Grounding, scientific explanation, and Humean laws

It has often been argued that Humean accounts of natural law cannot account for the role played by laws in scientific explanations. Loewer (Philosophical Studies 2012) has offered a new reply to this argument on behalf of Humean accounts—a reply that distinguishes between grounding (which Loewer portrays as underwriting a kind of metaphysical explanation) and scientific explanation. I will argue that Loewer’s reply fails because it cannot accommodate the relation between metaphysical and scientific explanation. This relation also resolves a puzzle about scientific explanation that Hempel and Oppenheim (Philosophy of Science 15:135–75, 1948) encountered.     

Realism,Rational Action,and the Humean Theory of Motivation

Realists about practical reasons agree that judgments regarding reasons are beliefs. They disagree, however, over the question of how such beliefs motivate rational action. Some adopt a Humean conception of motivation, according to which beliefs about reasons must combine with independently existing desires in order to motivate rational action; others adopt an anti-Humean view, according to which beliefs can motivate rational action in their own right, either directly or by giving rise to a new desire that in turn motivates the action. I argue that the realist who adopts a Humean model for explaining rational action will have a difficult time giving a plausible account of the role that desire plays in this explanation. I explore four interpretations of this role and argue that none allows a Humean theory to explain rational action as convincingly as an anti-Humean theory does. The first two models, in different ways, make acting on a reason impossible. The third allows this possibility, but only by positing a reason-sensitive desire that itself demands an explanation. The fourth avoids this explanatory challenge only by retreating to an empty form of the Humean view. In contrast, an anti-Humean theory can provide an intuitively plausible explanation of rational action. I conclude that the realist about reasons should adopt an anti-Humean theory to explain rational action.

In Defence of Proportionalism

In his book Slaves of the Passions, Mark Schroeder defends a Humean theory of reasons. Humeanism is the view that you have a reason to X only if X‐ing promotes at least one of your desires. But Schroeder rejects a natural companion theory of the weight of reasons, which he calls proportionalism. According to it, the weight of a reason is proportionate to the strength of the desire that grounds it and the extent to which the act promotes the object of that desire. In this paper, I aim to do three things: (1) to show why Schroeder's arguments against proportionalism do not refute it; (2) to identify the real trouble with proportionalism; and (3) to suggest a better way of understanding it (preferentialism). According to this theory, the overall strength of reasons is determined by the agent's preferences.     

La Bohume

This paper critically assesses whether quantum entanglement can be made compatible with Humean supervenience. After reviewing the prima facie tension between entanglement and Humeanism, I outline a recently-proposed Humean response, and argue that it is subject to two problems: one concerning the determinacy of quantities, and one concerning its relationship to scientific practice.

     

Laws and Lawlessness

I develop a metaphysical position that is both lawless and anti-Humean. The position is called realist lawlessness and contrasts with both Humean lawlessness and nomological realism – the claim that there are laws in nature. While the Humean view also allows no laws, realist lawlessness is not Humean because it accepts some necessary connections in nature between distinct properties. Realism about laws, on the other hand, faces a central dilemma. Either laws govern the behaviour of properties from the outside or from the inside. If the former, an unacceptable quidditist view of properties follows. But no plausible account of laws within properties can be developed that permits a governing role specifically for laws. I conclude in favour of eliminativism about laws. At the conceptual core, the notion of a law in nature is misleading. It is suggestive of an otherwise static world in need of animation.     

NON‐RELATIVE REASONS AND HUMEAN THOUGHT: IF WHAT IS A REASON FOR YOU IS A REASON FOR ME,WHERE DOES THAT LEAVE THE HUMEAN?

Abstract: A variety of strategies have been used to oppose the influential Humean thesis that all of an agent's reasons for action are provided by the agent's current wants. Among these strategies is the attempt to show that it is a conceptual truth that reasons for action are non‐relative. I introduce the notion of a basic reason‐giving consideration and show that the non‐relativity thesis can be understood as a corollary of the more fundamental thesis that basic reason‐giving considerations are generalizable. I then consider the relationship between the generalizability thesis and the Humean thesis that all of an agent's reasons for action are provided by the agent's current wants. I argue that, contrary to a common assumption, there is a subtle and clearly motivated version of the Humean thesis that does not deny, and so is not threatened by, the generalizability thesis.     

Scientific Representation: Paradoxes of Perspective

David Lewis is a natural target for those who believe that findings in quantum physics threaten the tenability of traditional metaphysical reductionism. Such philosophers point to allegedly holistic entities they take both to be the subjects of some claims of quantum mechanics and to be incompatible with Lewisian metaphysics. According to one popular argument, the non-separability argument from quantum entanglement, any realist interpretation of quantum theory is straightforwardly inconsistent with the reductive conviction that the complete physical state of the world supervenes on the intrinsic properties of and spatio-temporal relations between its point-sized constituents. Here I defend Lewis's metaphysical doctrine, and traditional reductionism more generally, against this alleged threat from quantum holism. After presenting the non-separability argument from entanglement, I show that Bohmian mechanics, an interpretation of quantum mechanics explicitly recognized as a realist one by proponents of the non-separability argument, plausibly rejects a key premise of that argument. Another holistic worry for Humeanism persists, however, the trouble being the apparently holistic character of the Bohmian pilot wave. I present a Humean strategy for addressing the holistic threat from the pilot wave by drawing on resources from the Humean best system account of laws.     

Defending Desire: Scanlon's Anti-Humeanism

In the opening chapter of What We Owe To Each Other , Tim Scanlon produces a sustained critique of a Humean conception of practical reason. Scanlon claims he will argue that unless having a desire just is to see something as a reason, desires play (almost) no role in the explanation or justification of action. Yet his specific arguments against Humeanism all employ a very austere understanding of desire (which he calls the "standard model"), and attempt to show that desires so understood are not up to any explanatory or justificatory task. Since the standard model represents only one understanding of desire (distinct from the "recognition of reasons") his specific arguments cannot establish his stated general thesis. I show how a more robust conception of desire will leave the Humean account safe from Scanlon's specific arguments.     

A Defense of Humeanism from Nagel's Persimmon

This paper defends Humeanism: the view that an agent has a reason for an intentional action if and only if it fulfills, or is a means to fulfilling, a current desire of that agent. Thomas Nagel presents an example involving a short-lived desire for eating a persimmon tomorrow. He claims that, contrary to Humeanism, this example is a clear case of irrationality. Furthermore, the Humean cannot simply dismiss all current desires with future objects, because desires of this sort are crucial to the Humean account of prudence. I respond that, correctly understood, Humeanism can simultaneously account for prudent conduct and other conduct motivated by present desires with future objects.     

True-to-Hume laws and the open-future (or Hypertemporal Humeanism)

Take open-future Humeanism to comprise the following four tenets: (T1) that truth supervenes on a mosaic of local particular matters of fact; (T2) that there are no necessary connections between distinct existences; (T3) that there is a dynamic present moment; and (T4) that there are no future facts; that is, contingent propositions about the future obtain truth values only when their referents are actualised. Prima facie this is a deeply problematic metaphysic for the Humean, since given that the widely accepted Humean conception takes all truths (inclusive of nomological truths) to supervene on an omnitemporal mosaic of local particular matters of fact, if there are no future facts, then the Humean can neither provide laws of nature, nor justify many everyday inductive inferences. However, I argue that this eternalist metaphysic is in tension with at least one of Hume’s central metaphysical claims concerning causation, e.g. that causal regularities may cease to hold at any time. In this paper I propose and defend one possible open-future Humean metaphysic which admits of “true-to-Hume” causal and nomological facts. Furthermore, although I am happy to concede that induction is problematic for the open-future Humean, I demonstrate that it poses no greater threat to the open-future conception than it does to the popular Lewisian conception of natural law.     

Where No Mind Has Gone Before: Exploring Laws in Distant and Lonely Worlds

Do the laws of nature supervene on ordinary, non‐nomic matters of fact? Lange’s criticism of Humean supervenience (HS) plays a key role in his account of natural laws. Though we are sympathetic to his account, we remain unconvinced by his criticism. We focus on his thought experiment involving a world containing nothing but a lone proton and argue that it does not cast sufficient doubt on HS. In addition, we express some concern about locating the lawmakers in an ontology of primitive subjunctive facts and suggest that a ‘mixed’ metaphysics to the lawmaker question might be attractive.     

John Stuart Mill,Determinism, and the Problem of Induction

Auguste Comte's doctrine of the three phases through which sciences pass (the theological, the metaphysical, and the positive) allows us to explain what John Stuart Mill was attempting in his magnum opus, the System of Logic: namely, to move the science of logic to its terminal and ‘positive’ stage. Both Mill's startling account of deduction and his unremarked solution to the Humean problem of induction eliminate the notions of necessity or force—in this case, the ‘logical must’—characteristic of a science's metaphysical stage. Mill's treatment had a further surprising payoff: his solution to the Problem of Necessity (what today we call the problem of determinism and freedom of the will).     

Hume's “Wilt Chamberlain Argument” and taxation

Robert Nozick addresses the idea of egalitarian redistribution in an argument standardly considered original: the “Wilt Chamberlain Argument”. However, this argument (without reference to Wilt Chamberlain) is found in David Hume's AnEnquiry Concerning the Principles of Morals, first published in 1751. Placing this argument within a Humean and Hayekian, rather than a Lockean or Kantian, perspective radically changes its import for issues of economic justice. Rather than vindicating the radical individualism of Nozick and other libertarians, applied to our circumstances using Hume's conventionalist and evolutionary account of justice, Hume's Wilt Chamberlain argument vindicates moderate redistribution constrained by the rule of general laws and the goal of fostering innovation and industriousness.     

A priori causal laws

Sober and Elgin defend the claim that there are a priori causal laws in biology. Lange and Rosenberg take issue with this on Humean grounds, among others. I will argue that Sober and Elgin don’t go far enough – there are a priori causal laws in many sciences. Furthermore, I will argue that this thesis is compatible with a Humean metaphysics and an empiricist epistemology.     

Humean nomic essentialism

Humeanism – the idea that there are no necessary connections between distinct existences – and Nomic Essentialism – the idea that properties essentially play the nomic roles that they do – are two of the most important and influential positions in the metaphysics of science. Traditionally, it has been thought that these positions were incompatible competitors. We disagree. We argue that there is an attractive version of Humeanism that captures the idea that, for example, mass essentially plays the role that it actually does in the laws of nature. In this paper we consider the arguments that have lead many to conclude that Humeanism cannot be combined with Nomic Essentialism; we identify the weaknesses in these arguments; and we argue in detail that a version of Humeanism based on a variant of the Best System account of laws captures the key intuitions behind nomic essentialism.     

Postmodernism's Self-Nullifying Reading of Nietzsche

In his very rich and insightful book, Kant's Theory of Freedom, Henry Allison argues that in the first Critique Kant's reason for rejecting Humean compatibilism in favor of an incompatibilist conception of practical freedom stems, not from a specific concern to ground morality, as many have supposed, but from his general conception of rational agency, which Allison explicates in terms of the idea of practical spontaneity. Practically spontaneous rational agency is subject to imperatives and therefore distinct from Humean agency. But it is not necessarily subject to the categorical imperative and hence is distinct from fully spontaneous (transcendentally free) moral agency. A conception thus emerges of an agent with limited spontaneity, subject to hypothetical but not categorical imperatives. A doubt may be raised, however, as to whether Kant's view can accommodate this conception of limited practical spontaneity. Reflection on Kant's notion of a hypothetical imperative suggests that the idea of limited spontaneity is in danger of either collapsing into the Humean picture or else turning out to be equivalent to the conception of full spontaneity appropriate to moral agency. There is thus reason to suppose that, for Kant, we would not be bound by imperatives at all if we were not bound by the categorical imperative.     

The inertness of reason and Hume's legacy

Hume argues against the seventeenth-century rationalists that reason is impotent to motivate action and to originate morality. Hume's arguments have standardly been considered the foundation for the Humean theory of motivation in contemporary philosophy. The Humean theory alleges that beliefs require independent desires to motivate action. Recently, however, new commentaries allege that Hume's argument concerning the inertness of reason has no bearing on whether beliefs can motivate. These commentaries maintain that for Hume, beliefs about future pleasurable and painful objects on their own can produce the desires that move us to action. First, I show that this reading puts Hume at odds with Humeans, since the latter are committed, not only to the view that beliefs and desires are both necessary to action, but also to the view that beliefs do not produce desires. Second, I review textual, philosophical and historical grounds for my interpretation of Hume's argument for the inertness of reason. I argue that the new line on Hume, while consistent with a certain reading of the Treatise, is not supported by the Dissertation on the Passions and the second Enquiry, where Hume argues that all motivation has an origin in “taste”, which I take to be different from belief. Thus, Hume's arguments do support the contemporary Humean theory of motivation.