A polemical account of Australian philosophy up to 2003, emphasising its unique aspects (such as commitment to realism) and the connections between philosophers' views and their lives. Topics include early idealism, the dominance of John Anderson in Sydney, the Orr case, Catholic scholasticism, Melbourne Wittgensteinianism, philosophy of science, the Sydney disturbances of the 1970s, Francofeminism, environmental philosophy, the philosophy of law and Mabo, ethics and Peter Singer. Realist theories especially praised are David Armstrong's on universals, David Stove's on logical probability (...) and the ethical realism of Rai Gaita and Catholic philosophers. In addition to strict philosophy, the book treats non-religious moral traditions to train virtue, such as Freemasonry, civics education and the Greek and Roman classics. (shrink)

Although the doctrine of divine simplicity has faced substantial criticism in recent years, Jeffrey Brower has recently offered a novel defense of the view by appealing to contemporary truthmaker theory. In this paper, I will argue that Brower’s defense of divine simplicity requires an implausible account of how truthmaking works for essential intrinsic predications. I will first argue that, unless Brower is willing to make an ad hoc exception for how truthmaking works in God’s case, he is committed to saying (...) that essential intrinsic predications about any object are made true by that object alone, not by its having essential properties. I will then argue that reflecting on cases where distinct essential intrinsic predications about an object have different causal explanations behind them shows that this general view of truthmaking is implausible. (shrink)

The possibility of multi-location—of one entity having more than one exact location—is required by several metaphysical theories such as the immanentist theory of universals and three-dimensionalism about persistence. One of the most pressing challenges for multi-location theorists is that of making sense of exact location—in that extant definitions of exact location entail a principle called ‘functionality’, according to which nothing can have more than one exact location. Recently in a number of promising papers, Antony Eagle has proposed and defended a (...) definition of exact location in terms of weak location that does not entail functionality. This paper provides the first thorough assessment of Eagle’s proposal. In particular, we argue that it cannot account for the location of immanent universals, the multi-location of mereologically changing three-dimensional objects, the multi-location of mereologically complex objects, and that it makes extended simples impossible. (shrink)

Presentists face a challenge from truthmaker theory: if you hold both that the only existing objects are presently existing and that truth supervenes on being, then you will be hard pressed to identify some existent on which a given true but traceless claim about the past supervenes. One reconciliation strategy, advocated by Cameron (2011), is to appeal to distributional properties so to serve as presently existing truthmakers for past truths. I argue that a presentist ought to deny that distributional properties (...) can serve as truthmakers. (shrink)

Mathematics has a great variety ofapplications in the physical sciences.This simple, undeniable fact, however,gives rise to an interestingphilosophical problem:why should physical scientistsfind that they are unable to evenstate their theories without theresources of abstract mathematicaltheories? Moreover, theformulation of physical theories inthe language of mathematicsoften leads to new physical predictionswhich were quite unexpected onpurely physical grounds. It is thought by somethat the puzzles the applications of mathematicspresent are artefacts of out-dated philosophical theories about thenature of mathematics. In this paper I argue (...) that this is not so.I outline two contemporary philosophical accounts of mathematics thatpay a great deal of attention to the applicability of mathematics and showthat even these leave a large part of the puzzles in question unexplained. (shrink)

Paul Benacerraf's argument from multiple reductions consists of a general argument against realism about the natural numbers (the view that numbers are objects), and a limited argument against reductionism about them (the view that numbers are identical with prima facie distinct entities). There is a widely recognized and severe difficulty with the former argument, but no comparably recognized such difficulty with the latter. Even so, reductionism in mathematics continues to thrive. In this paper I develop a difficulty for Benacerraf's argument (...) against reductionism that is of comparable severity to the now widely recognized difficulty with his general argument against realism. Thanks to Kit Fine, Hartry Field, Jeff Sebo, Ted Sider, Stephen Schiffer, and anonymous referees at Philosophia Mathematica for helpful comments on earlier versions of this paper. Thanks to Aron Edidin for many helpful discussions of the problems that inspired it. CiteULike Connotea Del.icio.us What's this? (shrink)

The truth-making principle is one of the main subjects in contemporary meta- physics, and this paper is an elementar exposition of the main issues of the on-going debate. I will proceed as follows. First, I will expose the basics, including the principle’s range, the main kinds of truth-making, the main interpretations of the principle, and some applications. Second, I will expose some technical issues about ontological commitment, reification, necessity, reality, and truth.

Three plausible views—Presentism, Truthmaking, and Independence—form an inconsistent triad. By Presentism, all being is present being. By Truthmaking, all truth supervenes on, and is explained in terms of, being. By Independence, some past truths do not supervene on, or are not explained in terms of, present being. We survey and assess some responses to this.

Together, these entail that for every true proposition p, there exists some thing which could not exist and p be false.

There is widespread disagreement as to what the facts are concerning just when a collection of objects composes some further object; but there is widespread agreement that, whatever those facts are, they are necessary. I am unhappy to simply assume this, and in this paper I ask whether there is reason to think that the facts concerning composition hold necessarily. I consider various reasons to think so, but find fault with each of them. I examine the theory of composition as (...) identity, but argue that the version of this doctrine that entails universalism is implausible. I consider the claim that the a priority of such facts leads to their necessity, but give a defence of substantial contingent a priori truths. I ask whether the contingency of such facts would lead to unwelcome possibilities, but argue that the worrying looking possibilities can be blocked if it is desired. Next, I argue against the thought that the Lewis-Sider argument against restricted composition might give us reason to accept the necessity of universalism. Lastly, I respond to two objections from the 2006 BSPC. I conclude in favour of the contingency of the facts concerning when some things compose some thing. (shrink)

What are the ontological commitments of a sentence? In this paper I offer an answer from the perspective of the truthmaker theorist that contrasts with the familiar Quinean criterion. I detail some of the benefits of thinking of things this way: they include making the composition debate tractable without appealing to a neo-Carnapian metaontology, making sense of neo-Fregeanism, and dispensing with some otherwise recalcitrant necessary connections.

There is a traditional theistic doctrine, known as the doctrine of divine simplicity, according to which God is an absolutely simple being, completely devoid of any metaphysical complexity. On the standard understanding of this doctrine—as epitomized in the work of philosophers such as Augustine, Anselm, and Aquinas—there are no distinctions to be drawn between God and his nature, goodness, power, or wisdom. On the contrary, God is identical with each of these things, along with anything else that can be predicated (...) of him intrinsically. (shrink)

According to the doctrine of divine simplicity, God is an absolutely simple being lacking any distinct metaphysical parts, properties, or constituents. Although this doctrine was once an essential part of traditional philosophical theology, it is now widely rejected as incoherent. In this paper, I develop an interpretation of the doctrine designed to resolve contemporary concerns about its coherence, as well as to show precisely what is required to make sense of divine simplicity.

I propose an account truthmaking that provides truthmakers for negative truths. The account replaces Truthmaker Necessitarianism with a "Duplication Principle", according to which a suitable entity T is a truthmaker for a proposition P just in case the existence of an appropriate counterpart of T entails the truth of P, where the counterpart relation is cashed out in terms of qualitative duplication. My account captures an intuitive notion of truthmakers as "things the way they are", validates two appealing principles about (...) entailment and containment proposed by David Armstrong, and invalidates the controversial Disjunction Thesis. (shrink)

17th-century Iberian and Italian scholastics had a concept of a truthmaker [verificativum] similar to that found in contemporary metaphysical debates. I argue that the 17th-century notion of a truthmaker can be illuminated by a prevalent 17th-century theory of truth according to which the truth of a proposition is the mereological sum of that proposition and its intentional object. I explain this theory of truth and then spell out the account of truthmaking it entails.

It is sometimes supposed that, in principle, we cannot offer an explanation for why there is something rather than nothing. I argue that this supposition is a mistake, and stems from a needlessly myopic conception of the form explanations can legitimately take. After making this more general point, I proceed to offer a speculative suggestion regarding one sort of explanation which can in principle serve as an answer to the question “why is there something rather than nothing?” The suggestion is (...) that there may be something rather than nothing in virtue of the truth of certain sorts of subjunctive conditionals. (shrink)

(No abstract is available for this citation).

In his (2002) Gonzalo Rodriguez-Pereyra provides a powerful articulation of the claim that Resemblance Nominalism provides the best answer to the so-called Problem of Universals. Resemblance Nominalism has not been popular for some time, and one influential reason for this is the widespread belief that Resemblance Nominalism cannot dispense with all universals. The realist critics appeal to what is known as Russell’s Regress (cf. Russell 1997). If properties are to be explained in terms of one object’s resembling another, then this (...) seems to leave the relational property of resemblance itself unexplained. The critics’ objection is that this property itself must be explained by a dyadic universal of resemblance. (shrink)

Jeffrey Brower has recently articulated a way to make sense of the doctrine of divine simplicity using resources from contemporary truthmaker theory. Noël Saenz has advanced two objections to Brower’s account, arguing that it violates constraints on adequate metaphysical explanations at various points. I argue that Saenz’s objections fail to show that Brower’s account is explanatorily inadequate.

Presentism faces a serious challenge from truthmaker theory. Standard solutions to the truthmaker objection against presentism proceed in one of two ways. Easy road presentists invoke new entities to satisfy the requirements of truthmaker theory. Hard road presentists, by contrast, flatly refuse to give in to truthmaker demands. Recently, a third way has been proposed. This response seeks to address the truthmaking problem by tensing our truthmaker principles. These views, though intuitive, are under-developed. In this paper, I get serious about (...) a fundamentally tensed approach to truthmaking by sketching out the underlying ontological picture needed to make sense of tensed truthmaker theory. (shrink)

Recent attempts to resolve the truthmaker objection to presentism employ a fundamentally tensed account of the relationship between truth and being. On this view, the truth of a proposition concerning the past supervenes on how things are, in the present, along with how things were, in the past. This tensed approach to truthmaking arises in response to pressure placed on presentists to abandon the standard response to the truthmaker objection, whereby one invokes presently existing entities as the supervenience base for (...) the truth of past-directed propositions. In this paper, I argue that a fundamentally tensed approach to truthmaking is implausible because it requires the existence of cross-temporal supervenience relations, which are anathema to presentism. (shrink)

In this paper I consider the aboutness objection against standard truth-preserving presentism (STP). According to STP: (1) past-directed propositions (propositions that seem to be about the past) like , are sometimes true (2) truth supervenes on being and (3) the truth of past-directed propositions does not supervene on how things were, in the past. According to the aboutness objection (3) is implausible, given (1) and (2): for any proposition, P, P ought to be true in virtue of what P is (...) about, and so it is upon the past that the truth of past-directed propositions ought to supervene. Although an objection along these lines has been offered previously, I press the objection in two ways. First, by providing needed support for the view that propositions ought to be true in virtue of what they are about and, second, by arguing that the two responses available to the proponent of STP fail to be compelling. (shrink)

Strong non-maximalism holds that some truths require no ontological ground of any sort. Strong non-maximalism allows one to accept that some propositions are true without being forced to endorse any corresponding ontological commitments. We show that there is a version of truthmaker theory available—anti-aboutness truthmaking—that enjoys the dialectical benefits of the strong non-maximalist’s position. According to anti-aboutness truthmaking, all truths require grounds, but a proposition need not be grounded in the very thing(s) that the proposition is about. We argue that (...) if strong non-maximalism can be defended, then so can anti-aboutness truthmaking on the very same basis; one can enjoy the benefits of strong non-maximalism without giving up on the idea that truth is always grounded in being. (shrink)

We defend two claims: (1) if one is attracted to a strong non-maximalist view about truthmaking, then it is natural to construe this as the view that there exist fundamental truths; (2) despite considerable aversion to fundamental truths, there is as yet no viable independent argument against them. That is, there is no argument against the existence of fundamental truths that is independent of any more specific arguments against the ontology accepted by the strong non-maximalist. Thus there is no argument (...) that the strong non-maximalist herself will find dialectically motivating. (shrink)

Recently, nominalists have made a case against the Quine–Putnam indispensability argument for mathematical Platonism by taking issue with Quine’s criterion of ontological commitment. In this paper I propose and defend an indispensability argument founded on an alternative criterion of ontological commitment: that advocated by David Armstrong. By defending such an argument I place the burden back onto the nominalist to defend her favourite criterion of ontological commitment and, furthermore, show that criterion cannot be used to formulate a plausible form of (...) the indispensability argument. (shrink)

Many philosophers believe that truth is grounded: True propositions depend for their truth on the world. Some philosophers believe that truth’s grounding has implications for our ontology of time. If truth is grounded, then truth supervenes on being. But if truth supervenes on being, then presentism is false since, on presentism, e.g., that there were dinosaurs fails to supervene on the whole of being plus the instantiation pattern of properties and relations. Call this the grounding argument against presentism. Many presentists (...) claim that the grounding argument fails because, despite appearances, supervenience is compatible with presentism. In this paper, I claim that the grounding argument fails because, despite appearances, truth’s grounding gives the presentist no compelling reason to adopt the sort of supervenience principle at work in the grounding argument. I begin by giving two precisifications of the grounding principle: truthmaking and supervenience. In Sect. 2, I give the grounding argument against presentism. In Sect. 3, I argue that we should distinguish between eternalist and presentist notions of grounding; once this distinction is in hand, the grounding argument is undercut. In Sect. 4, I show how the presentist’s notion of grounding leads to presentist-friendly truthmaking and supervenience principles. In Sect. 5, I address some potential objections. (shrink)

Recent discussion of the problem of negative existentials for truthmaker theory suggests a modest solution to the problem: fully general negative truths like do not require truthmakers, whereas partially general negative truths like do. This modest solution provides a third alternative to the two standard solutions to the problem of negative existentials: the endorsement of truthmaker gaps, and the appeal to contentious ontological posits. We argue that this modest, middle-ground position is inconsistent with certain plausible general principles for truthmaking. The (...) only stable positions are to treat all negative truths as requiring truthmakers, or admit that no negative truths require truthmakers. Along the way, we explore some previously unaddressed questions for nonmaximalist truthmaker theory. (shrink)

Explanation has played myriad roles in truthmaker theory. The notion of explanation is sometimes thought to give content to the very idea of truthmaking, and is sometimes used as a weapon to undermine the entire point of truthmaker theory. I argue that the notion of explanation is dialectically useless in truthmaker theory: while it’s true that truthmaking offers a form of explanation, this claim is theoretically unilluminating, and leaves truthmaker theorists vulnerable to various kinds of attack. I advocate an alternative (...) approach to truthmaker theory that downplays the role of explanation, and show how it releases the enterprise from a variety of problematic commitments that have troubled truthmaker theorists. The “ontology-first” approach to truthmaking that I advocate not only restores the initial impulse behind truthmaking, but also has a number of theoretical advantages. Most prominently, it dodges the infamous problem of negative existentials, and lessens truthmaker theory’s dependence on contentious intuitive judgments about both explanation and truthmaking. (shrink)

I argue that deflationary theories of truth reveal an important lesson for the broader theory of truth: although the notion of truthmaking has played an essential role in many traditional theories of truth, it can be separated from and survive the rejection of substantive theories of truth. I argue that many of the traditional substantive theories of truth are unified in defining truth in terms of the ontological grounds that are needed to account for truth. Deflationists reject the idea that (...) a theory of truth needs such metaphysical implications, but in so doing they need not rule out the possibility of developing an independently motivated theory of truthmaking. I argue that deflationists can and should embrace truthmaker theory, once it is shorn from its connection to the traditional project of defining truth. (shrink)

Truthmaker necessitarianism is the view that an object is a truthmaker for a truth-bearer only if it is impossible for the object to exist and the truth-bearer be false. While this thesis is widely regarded as truthmaking "orthodoxy", it is rarely explicitly defended. In this paper I offer an argument in favor of necessitarianism that raises the question of what the truthmakers are for the truths about truthmaking. The supposed advantages of non-necessitarianism dissolve once we take these truths into account.

It is a common criticism of presentism – the view according to which only the present exists – that it errs against truthmaker theory. Recent attempts to resolve the truthmaker objection against presentism proceed by restricting truthmaker maximalism (the view that all truths have truthmakers), maintaining that propositions concerning the past are not made true by anything, but are true nonetheless. Support for this view is typically garnered from the case for negative existential propositions, which some philosophers contend are exceptions (...) to truthmaker maximalism. In this article, we argue that a ‘no truthmakers’ approach to the truthmaker objection is critically flawed. (shrink)

Realism and anti-realism about a domain of thought are metaphysical theses that involve the natures of the truthmakers in that domain and the truthmaking relation that is operant in the domain. Truthmaker theory is not exclusive territory for realists: anti-realist views are also best understood in terms of how they understand truthmakers and truthmaking. In particular, I explore the possibility of projectivist truthmaking, and show how it makes sense of quasi-realism. In addition to critically examining some extant accounts of the (...) relationship between realism and truthmaking, I offer an account that best captures the nature of the various realism debates. (shrink)

I argue that there is no metaphysically substantive property of truth. Although many take this thesis to be central to deflationism about truth, it is sometimes left unclear what a metaphysically substantive property of truth is supposed to be. I offer a precise account by relying on the distinction between the property and concept of truth. Metaphysical substantivism is the view that the property of truth is a sparse property, regardless of how one understands the nature of sparse properties. I (...) then offer two new arguments against metaphysical substantivism that employ ideas involving recombination and truthmaking. First, I argue that there are no theoretically compelling reasons to posit the existence of a metaphysically substantive property of truth. Secondly, I argue that if we do posit the existence of such a property, then we end up with a view that is either contradictory or unmotivated. What we’re left with is a metaphysically deflationary account of the property of truth that fully respects the metaphysical ambitions of truthmaker theory, and that is consistent with both the view that truth is a deflated, explanatorily impotent concept and the view that truth is an explanatorily powerful concept. (shrink)

The present paper is a continuation of a previous one by the same title, the content of which faced the issue concerning the relations of coreference and qualification in compliance with the Navya-Nyāya theoretical framework, although prompted by the Advaita-Vedānta enquiry regarding non-difference. In a complementary manner, by means of a formal analysis of equivalence, equality, and identity, this section closes the loop by assessing the extent to which non-difference, the main issue here, cannot be reduced to any of the (...) former. The following sections of this study will focus on the assessment of the eventual possibility of causation and transformation in non-difference. (shrink)

This paper is an investigation in the use of truthmaker theory for exploring the relation of logic to world, and as a tool for metaphysics. A variant of truthmaker theory, which we call the simple theory, is defined and defended against objections. It is characterized formally, and its central features are derived. As part of this project, we give a formal metaphysics based on nondeterministic necessitation relations among possible entities. In what is called the fundamental theorem of truthmaking, it is (...) shown that, as long as a logic is sound and complete, its inferential structure will be isomorphic to the necessitation structure of our metaphysics. We thus arrive at a purely structural logic–world relationship which can be used for metaphysical investigations. Other products of our investigation are a sound and complete semantics for first-order logic with identity and a solution to a result of Restall which has threatened to make truthmaker theory trivial. (shrink)

Predication is an indisputable part of our linguistic behavior. By contrast, the metaphysics of predication has been a matter of dispute ever since antiquity. According to Plato—or at least Platonism, the view that goes by Plato’s name in contemporary philosophy—the truths expressed by predications such as “Socrates is wise” are true because there is a subject of predication (e.g., Socrates), there is an abstract property or universal (e.g., wisdom), and the subject exemplifies the property.1 This view is supposed to be (...) general, applying to all predications, whether the subject of predication is a person, a planet, or a property.2 Despite the controversy surrounding the metaphysics of predication, many theistic philosophers—including the majority of contemporary analytic theists—regard Platonism as extremely attractive. At the same time, however, such philosophers are also commonly attracted to a form of traditional theism that has at its core the thesis that God is an absolutely independent.. (shrink)

Truthmaker theorists hold that propositions about higher-level entities (e.g. the proposition that there is a heap of sand) are often made true by lower-level entities (e.g. by facts about the configuration of fundamental particles). This generates a problem: what should we say about these higher-level entities? On the one hand, they must exist (since there are true propositions about them), on the other hand, it seems that they are completely superfluous and should be banished for reasons of ontological parsimony. Some (...) truthmaker theorists—most prominently David Armstrong—have tried to solve this puzzle by arguing that these entities are ‘an ontological free lunch’, i.e. real existents that are still ‘no addition of being’. This answer is prima facie attractive, but I argue in this paper that the standard approaches to truthmaking—modal theories and grounding theories—are unable to vindicate the doctrine of the ontological free lunch, and thus fail to solve the problem of higher-level entities. Fortunately, there is a non-standard account of truthmaking available, the reductive explanation account, which succeeds where the standard approaches fail. (shrink)

Quantity is the first category that Aristotle lists after substance. It has extraordinary epistemological clarity: "2+2=4" is the model of a self-evident and universally known truth. Continuous quantities such as the ratio of circumference to diameter of a circle are as clearly known as discrete ones. The theory that mathematics was "the science of quantity" was once the leading philosophy of mathematics. The article looks at puzzles in the classification and epistemology of quantity.

Lewis's notion of a "natural" property has proved divisive: some have taken to the notion with enthusiasm, while others have been sceptical. However, it is far from obvious what the enthusiasts and the sceptics are disagreeing about. This paper attempts to articulate what is at stake in this debate.

For the framework of event causation—i.e. the framework according to which causation is a relation between events—absences or omissions pose a problem. Absences, it is generally agreed, are not events; so, under the framework of event causation, they cannot be causally related. But, as a matter of fact, absences are often taken to be causes or effects. The problem of absence causation is thus how to make sense of causation that apparently involves absences as causes or effects. In an influential (...) paper, Helen Beebee offers a partial solution to the problem by giving an account of causation by absence. I argue that Beebee's account can be extended to cover causation of absence as well. More importantly, I argue that the extended Beebeeian account calls for a major modification to David Lewis's theory of causal explanation, usually taken as standard. Compared to the standard theory, the.. (shrink)

In §2-4, I survey three extant ways of making sense of indeterminate truth and find each of them wanting. All the later sections of the paper are concerned with showing that the most promising way of making sense of indeterminate truth is via either a theory of truthmaker gaps or via a theory of truthmaking gaps. The first intimations of a truthmaker–truthmaking gap theory of indeterminacy are to be found in Quine (1981). In §5, we see how Quine proposes to (...) solve Unger’s problem of the many via positing the possibility of groundless truth. In §6, I elaborate the truthmaker gap model of indeterminacy first sketched by Sorensen (2001, ch.11) and use it to give a reductive analysis of indeterminate truth. In §7, I briefly assess what kind of formal framework can best express the possibility of truthmaker gaps. In §8, I contrast what I dub ‘the ordinary conception of worldly indeterminacy’ with Williamson’s conception of worldly indeterminacy. In §9, I show how one can distinguish linguistic from worldly indeterminacy on a truthmaker gap conception. In §10, I briefly sketch the relationship between truthmaker gaps and ignorance. In §11, I assess whether a truthmaker gap conception of vagueness is really just a form of epistemicism. In §12, I propose that truthmaker gaps can yield a plausible model of (semantic) presupposition failure. In §13, in response to the worry that a truthmaker gap conception of indeterminacy is both parochial and controversial—since it commits us to an implausibly strong theory of truthmaking—I set forth a truthmaking gap conception of indeterminacy. In §14, I answer the worry that groundless truths, of whatever species, are just unacceptably queer. A key part of this answer is that a truthmaker–truthmaking gap model of indeterminacy turns out to be considerably less queer than any model of indeterminacy which gives up on Tarski’s T-schema for truth (and cognate schemas). (shrink)

Le Poidevin has recently presented an argument that gives rise to a serious problem for relationist theories of space. It appeals to the simple geometrical fact that if A, B and C are three points lying in a straight line, then AB and BC together entail AC. He suggests that an ontological relationship of supervenience must be appealed to to explain this entailment. Given this thesis of supervenience, relationism is implausible. I argue that the problem that Le Poidevin raises for (...) relationism should be rejected, because the thesis of supervenience is false. The latter rests upon what Le Poidevin refers to as ‘The explanatory principle', a principle which he claims to be a natural extension of the truthmaker principle. Contrary to this, I argue that given any plausible theory of truthmaking, the explanatory principle is false. With the rejection of this principle, Le Poidevin's argument against relationism collapses. (shrink)

Is the world internally connected by a web of necessary connections or is everything loose and independent? Followers of David Hume accept the latter by upholding Hume’s Dictum, according to which there are no necessary connections between distinct existences. Roughly put, anything can coexist with anything else, and anything can fail to coexist with anything else. Hume put it like this: “There is no object which implies the existence of any other if we consider these objects in themselves.” Since Hume’s (...) day, Hume’s Dictum has played a major role in philosophy, especially in contemporary metaphysics. In ruling out necessary connections, Hume’s Dictum implies that causal relations and the laws of nature are contingent. It makes other demands on our metaphysics of science as well; for example, it places restrictions on our metaphysics of counterfactuals, dispositions, and explanation. The principle has applications in other areas too. Hume’s Dictum places constraints on our theories of abstract objects and moral properties. For example, Hume’s Dictum rules out the view that moral properties are distinct from, but necessarily connected to, non-moral properties. While Hume’s Dictum is a prominent principle in metaphysics, few Humeans have defended the principle at length. It is assumed more often than it is argued for. As a result, Hume’s Dictum no longer enjoys the reputation it once did. It’s common to hear complaints about the lack of arguments in support of Hume’s Dictum. Moreover, philosophers are increasingly willing to defend views that are at odds with Hume’s Dictum. A striking example of this is the recent explosion of interest in views that take causal relations and the laws of nature to be necessary. Humeans can no longer afford to be complacent. An extended defense of Hume’s Dictum is called for, and that’s what this dissertation aims to offer. This dissertation has three parts. In the first part, I lay out some preliminaries and offer a precise formulation of Hume’s Dictum. In the second part, I develop three arguments in favor of Hume’s Dictum. In the final part, I defend Hume’s Dictum against objections. (shrink)