The connection between whole and part is intimate: not only can we share the same space, but I’m incapable of leaving my parts behind; settle the nonmereological facts and you thereby settle what is a part of what; wholes don’t seem to be an additional ontological commitment over their parts. Composition as identity promises to explain this intimacy. But it threatens to make the connection too intimate, for surely the parts could have made a different whole and the whole have (...) had different parts. In this paper I attempt to offer an account of parthood that is intimate enough but not too intimate: the parts generate the whole, but they are not themselves the whole. (shrink)

Many of us think that ordinary objects – such as tables and chairs – exist. We also think that ordinary objects have parts: my chair has a seat and some legs as parts, for example. But once we are committed to the (seemingly innocuous) thesis that ordinary objects are composed of parts, we then open ourselves up to a whole host of philosophical problems, most of which center on what exactly the composition relation is. Composition as Identity (CI) is the (...) view that the composition relation is the identity relation. While such a view has some advantages, there are many arguments against it. In this essay, I will briefly canvass three different varieties of Composition as Identity, and suggest why one of them should be preferred over the others. Then I will outline several versions of the most common objection against CI. I will suggest how a CI theorist can respond to these charges by maintaining that some of the arguments are invalid. (In part 2, I show how a CI theorist can maintain that the remaining arguments, while valid, are unsound). (shrink)

Many of us think that ordinary objects – such as tables and chairs – exist. We also think that ordinary objects have parts: my chair has a seat and some legs as parts, for example. But once we are committed to the (seemingly innocuous) thesis that ordinary objects are composed of parts, we then open ourselves up to a whole host of philosophical problems, most of which center on what exactly this composition relation is. Composition as Identity (CI) is the (...) view that the composition relation is the identity relation. While such a view has some advantages, there are many arguments against it. In this essay, I discuss several versions of the most common objection against CI, and show how the CI theorist can maintain that these arguments – contrary their initial intuitive appeal – are nonetheless unsound. (shrink)

It is plausible that the universe exists: a thing such that absolutely everything is a part of it. It is also plausible that singular, structured propositions exist: propositions that literally have individuals as parts. Furthermore, it is plausible that for each thing, there is a singular, structured proposition that has it as a part. Finally, it is plausible that parthood is a partial ordering: reflexive, transitive, and anti-symmetric. These plausible claims cannot all be correct. We canvass some costs of denying (...) each claim and conclude that parthood is not a partial ordering. Provided that the relevant entities exist, parthood is not anti-symmetric and proper parthood is neither asymmetric nor transitive. (shrink)

An encyclopedia entry which covers various revisionary conceptions of which macroscopic objects there are, and the puzzles and arguments that motivate these conceptions: sorites arguments, the argument from vagueness, the puzzles of material constitution, arguments against indeterminate identity, arguments from arbitrariness, debunking arguments, the overdetermination argument, and the problem of the many.

In this paper I assume that we have some intuitive knowledge—i.e. beliefs that amount to knowledge because they are based on intuitions. The question I take up is this: given that some intuition makes a belief based on it amount to knowledge, in virtue of what does it do so? We can ask a similar question about perception. That is: given that some perception makes a belief based on it amount to knowledge, in virtue of what does it do so? (...) A natural idea about perception is that a perception makes a belief amount to knowledge in part by making you sensorily aware of the concrete objects it is about. The analogous idea about intuition is that an intuition makes a belief amount to knowledge in part by making you intellectually aware of the abstract objects it is about. I expand both ideas into fuller accounts of perceptual and intuitive knowledge, explain the main challenge to this sort of account of intuitive knowledge (i.e. the challenge of making sense of intellectual awareness), and develop a response to it. (shrink)

Whether certain objects compose a whole at a given time does not seem to depend on anything other than the character of those objects and the relations between them. This observation suggests a far-reaching constraint on theories of composition. One version of the constraint has been explicitly adopted by van Inwagen and rules out his own answer to the composition question. The constraint also rules out the other well-known moderate answers that have so far been proposed.

Four-dimensionalism, the stage theory version in particular, has been defended as the best solution for avoiding vagueness in regards to composition, persistence and identity. Stage theory is highly problematic by itself, and the two views usually packed with it, unrestricted composition and counterpart theory, are a heavy burden. However, dispensing with these two views, four-dimensionalism could avoid vague persistence by issuing a criterion that would establish sharp temporal boundaries for the existence of genuine entities (simples, molecules and living organisms). This (...) would avoid vague existence and vague identity, but in a way that is still compatible with endurantism. Nevertheless, a minimal (substantialist) four-dimensionalism, a worm perdurantist ontology, would fit better with the unique way in which organisms persist: by retaining both identity and intrinsic change. (shrink)

Philosophical questions concerning parts and wholes have received a tremendous amount of the attention of contemporary analytic metaphysicians. In what follows, I discuss some of the central questions. The questions to be discussed are: how general is parthood? Are there different kinds of parthood or ways to be a part? Can two things be composed of the same parts? When does composition occur? Can material objects gain or lose parts? What is the logical form of the parthood relation enjoyed by (...) material objects? (shrink)

In this paper, I focus on three issues intertwined in current debates between endurantists and perdurantists—(i) the dimension of persisting objects, (ii) whether persisting objects have timeless, or only time-relative, parts, and (iii) whether persisting objects have proper temporal parts. I argue that one standard endurantist position on the first issue is compatible with standard perdurantist positions on parthood and temporal parts. I further argue that different accounts of persistence depend on the claims about objects' dimensions and not on the (...) auxiliary claims about parthood and temporal parts. (shrink)

A presentation of the Lewis-Sider argument from vagueness for unrestricted composition and possible responses.

David Lewis (1986) criticizes moderate views of composition on the grounds that a restriction on composition must be vague, and vague composition leads, via a precisificational theory of vagueness, to an absurd vagueness of existence. I show how to resist this argument. Unlike the usual resistance, however, I do not jettison precisificational views of vagueness. Instead, I blur the connection between composition and existence that Lewis assumes. On the resulting view, in troublesome cases of vague composition, there is an object, (...) which definitely exists, about which it is vague whether the relevant borderline parts compose it. (shrink)

A standard response to the problem of diachronic vagueness is ‘the semantic solution’, which demands an abundant ontology. Although it is known that the abundant ontology does not logically preclude endurantism, their combination is rejected because it necessitates massive coincidence between countless objects. In this paper, I establish that the semantic solution is available not only to perdurantists but also to endurantists by showing that there is no problem with such ubiquitous and principled coincidence.

Argument that Lewis and others are wrong that physicalism is if true then contingently true.

An age-old proposal that to be is to be a unity, or what I call a grouping, is updated and applied to the question “Why is there something rather than nothing?” (WSRTN). I propose the straight-forward idea that a thing exists if it is a grouping which ties zero or more things together into a new unit whole and existent entity. A grouping is visually manifested as the surface, or boundary, of the thing. In regard to WSRTN, when we subtract (...) away all existent entities, including the mind of the thinker, the resulting situation that we usually call “nothing would, by its very nature, be the whole amount, or entirety, of the situation. It completely defines the situation. The inherent nature of “nothing” is that it’s everything. Is there anything else besides that “nothing”? No. It is “nothing”, and this “nothing” is it, the all. A whole amount/entirety/all is a grouping, meaning that “nothing” is itself an existent entity. One objection might be that being a grouping is a property so how can it be there in “nothing”? The answer is that it is only once all known existent entities, including all properties and the mind visualizing this, are removed does this “nothing” gain the entirety/all grouping property. Therefore, the very lack of all existent entities is itself what allows this new property to be present and thereby to allow “nothing” to be an existent entity. This entirety/all grouping property is inherent, or intrinsic, to “nothing” and cannot be removed to get a more pure “nothing”. While the idea that “nothing” is a “something” that exists necessarily isn’t new, the grouping, or any, mechanism for how this can be so is. (shrink)

Let’s begin with a simple example. Consider two quarks: one near the tip of your nose, the other near the center of Alpha Centauri. Here is a question about these two subatomic particles: Is there an object that has these two quarks as its parts and that has no other parts? According to one view of the matter (a view that is surprisingly endorsed by a great many contemporary philosophers), the answer to this question is Yes. But I think it (...) is fair to say that according to common sense, the answer to this question is really No, there is no object that has as its only two parts a quark near the tip of your nose and another quark near the center of Alpha Centauri. (shrink)

Many of those who accept the universalist thesis that mereological composition is unrestricted also maintain that the folk typically restrict their quantifiers in such a way as to exclude strange fusions when they say things that appear to conflict with universalism. Despite its prima facie implausibility, there are powerful arguments for universalism. By contrast, there is remarkably little evidence for the thesis that strange fusions are excluded from the ordinary domain of quantification. Furthermore, this reconciliatory strategy seems hopeless when applied (...) to the more fundamental conflict between universalism and the intuitions that tell against it. (shrink)

Traditionally, this puzzle has been solved in various ways. Aristotle, for example, distinguished between “accidental” and “essential” changes. Accidental changes are ones that don't result in a change in an objects' identity after the change, such as when a house is painted, or one's hair turns gray, etc. Aristotle thought of these as changes in the accidental properties of a thing. Essential changes, by contrast, are those which don't preserve the identity of the object when it changes, such as when (...) a house burns to the ground and becomes ashes, or when someone dies. Armed with these distinctions, Aristotle would then say that, in the case of accidental changes, (1) and (2) are both false—a changing thing can really change one of its “accidental properties” and yet literally remain one and the same thing before and after the change. (shrink)

In The Principles of Mathematics, Russell writes: Whatever may be an object of thought, or may occur in any true or false proposition, or can be counted as one, I call a term. This, then, is the widest word in the philosophical vocabulary. I shall use as synonymous with it the words unit, individual and entity. The first two emphasize the fact that every term is one, while the third is derived from the fact that every term has being, i.e. (...) is in some sense. A man, a moment, a number, a class, a relation, a chimera, or anything else that can be mentioned, is sure to be a term'. Now in this remark, a certain extremely general, topic-neutral use of ‘object’ is singled out, a use in which the expression is treated as equivalent to (equally neutral) uses of ‘term’, ‘entity’, ‘unit’, ‘individual’, and ‘thing’. In addition, a claim is made to the effect that the content of the expression, with its emphasis on one, is such as to be adequate to comprehend the sum-total of existence, to include whatever there may be. The paper addresses the question of what this claim means, and whether it might be true. (shrink)

in Robin Le Poidevin (ed.) Being: Developments in Contemporary Metaphysics. Cambridge: Cambridge University Press. Peter van Inwagen claims that there are no tables or chairs. He also claims that sentences such as ‘There are chairs here’, which seem to imply their existence, are often true. This combination of views opens van Inwagen to a charge of self-contradiction. I explain the charge, and van Inwagen’s response to it, which involves the claim that sentences like ‘There are tables’ shift their truth-conditions between (...) different contexts of utterance. I present an alternative response which involves the negation of that claim, and argue that it is preferable to van Inwagen’s. (shrink)

Suppose you are asked to be the substitute teacher for a high school physics class. Suppose part of your assignment is to explain to the students all about the subatomic structure of a typical macroscopic object, such as a wooden table. Here is a speech that you are likely to find yourself making at some point during your lesson.

A critical survey of the fundamental philosophical issues in the logic and formal ontology of space, with special emphasis on the interplay between mereology (the theory of parthood relations), topology (broadly understood as a theory of qualitative spatial relations such as continuity and contiguity), and the theory of spatial location proper.

There will be a few themes. One to get us going: expansion versus contraction. About an object, o, and the region, R, of space(time) in which o is exactly located,1 we may ask: i) must there exist expansions of o: objects in filled superregions2 of R? ii) must there exist contractions of o: objects in filled subregions of..

There’s an argument around from so-called “linguistic theories of vagueness”, plus some relatively uncontroversial considerations, to powerful metaphysical conclusions. David Lewis employs this argument to support the mereological principle of unrestricted composition, and Theodore Sider employs a similar argument not just for unrestricted composition but also for the doctrine of temporal parts. This sort of argument could be generalised, to produce a lot of other less palatable metaphysical conclusions. However, arguments to Lewis’s and Sider’s conclusions on the basis of considerations (...) about vagueness are uncompelling, even if we accept the crucial premises about vagueness. And a good thing too, since the generalised form of the argument would prove far too much. (shrink)

In his excellent book, Four-Dimensionalism: An Ontology of Persistence and Time (Sider, 2001), Theodore Sider defends a version of four-dimensionalism which he calls the ‘stage-theory’. This paper focuses on Sider's argument from vagueness and argues that, due to the problematic nature of the argument from vagueness, Sider’s case in favor of four-dimensionalism is in the end not successful.

Three-dimensionalists , sometimes referred to as endurantists, think that objects persist through time by being “wholly present” at every time they exist. But what is it for something to be wholly present at a time? It is surprisingly difficult to say. The threedimensionalist is free, of course, to take ‘is wholly present at’ as one of her theory’s primitives, but this is problematic for at least one reason: some philosophers claim not to understand her primitive. Clearly the three-dimensionalist would be (...) better off if she could state her theory in terms accessible to all. We think she can. What is needed is a definition of ‘is wholly present at’ that all can understand. in this paper, we offer one. (shrink)

Worlds where things divide forever ("gunk" worlds) are apparently conceivable. The conceivability of such scenarios has been used as an argument against "nihilist" or "near-nihilist" answers to the special composition question. I argue that the mereological nihilist has the resources to explain away the illusion that gunk is possible.

In this paper, I critically discuss one of the more influential arguments for mereological universalism, what I will call ‘the Vagueness Argument’. I argue that a premise of the Vagueness Argument is not well supported and that there are at least two good reasons for thinking that the premise in question is false.

Persistence through time is like extension through space. A road has spatial parts in the subregions of the region of space it occupies; likewise, an object that exists in time has temporal parts in the various subregions of the total region of time it occupies. This view — known variously as four dimensionalism, the doctrine of temporal parts, and the theory that objects “perdure” — is opposed to “three dimensionalism”, the doctrine that things “endure”, or are “wholly present”.1 I will (...) attempt to resolve this dispute in favor of four dimensionalism by means of a novel argument based on considerations of vagueness. But before argument in this area can be productive, I believe we must become much clearer than is customary about exactly what the dispute is, for the usual ways of formulating the dispute are flawed, especially where three dimensionalism is concerned. (shrink)

‘Restricted composition’ says that there are some composite objects. And it says that some objects jointly compose nothing at all. The main threat to restricted composition is the influential and widely defended Vagueness Argument. We shall see that the Vagueness Argument fails. In seeing how this argument fails, we shall discover a new focus for the debate over composition's extent.

Although the Evans argument against vague identity has been much discussed, proposah for blocking it have not so far satisfied general conditions which any solution ought to meet. Moreover, the relation between ontically vague identity and ontic vagueness more generally has not yet been satisfactorily addressed. I advocate a way of resisting the Evans argument which satisfies the conditions. To show how this approach can vindicate particular cases of ontically vague identity, I develop a framework for describing ontic vagueness in (...) general in terms of multiple actualities. This provides aprìncipled approach to ontically vague identity which is unaffected by the Evans argument. (shrink)

I formulate a theory of persistence in the endurantist family and pose a problem for the conjunction of this theory with orthodox versions of special or general relativity. The problem centers around the question: Where are things?

In this paper, we argue that time travel is problematic for the endurantist. For it appears to be possible, given time travel, to construct a wall out of a single time travelling brick. This commits the endurantist to one of the following: (a) the wall is composed of the time travelling brick many times over; (b) the wall does not in fact exist at all; (c) the wall is identical to the brick. We argue that each of these options is (...) unsatisfactory. (shrink)

Many philosophers think that, necessarily, any material objects have a fusion (let’s call that doctrine “Universalism”). In this paper I point out a couple of strange consequences of Universalism and related doctrines, and suggest that they are strange enough to constitute a powerful argument against those views.

I offer a new criticism of the argument from vagueness to four-dimensionalism [Sider 2001. The argument is modelled after an older argument for mereological universalism [Lewis 1986 and may be looked upon as a tightened-up and extended version of the latter. While I agree with other critics [Koslicki 2003; Markosian 2004 that the argument from vagueness fails precisely because of this affinity, my recipe for dealing with it is different. I reject the assumption, shared by Sider with his opponents, that (...) synchronic composition and ‘minimal diachronic fusion’ are sufficiently similar to use considerations inspired by the analysis of the former to bear on the latter. My objection to a crucial premise of the argument from vagueness turns on the relevant aspect of dissimilarity between these two cases. (shrink)

manuscript delves into the philosophical debate surrounding the Special Composition Question (SCQ), focusing on the causal relationships between objects and their constituent parts. By distinguishing between Weak and Strong Causal Composition, the article explores how causal mechanisms underpin the composition of objects. Theories from notable philosophers, including van Inwagen and Leibniz, are evaluated. This study seeks to bridge the gap between common sense perspectives and principled ontological theories by introducing the concepts of Weak and Strong Causal Composition. The analysis reveals (...) how a causal approach can offer insightful resolutions to longstanding debates in mereology and ontology, emphasizing the role of causality in understanding the essence of material composition. The proposed causal perspective encourages further philosophical inquiry into the foundational principles governing the composition of objects. (shrink)

Almost all philosophers interested in parthood and composition think that a composite object is a further thing, numerically distinct from the objects that compose it. Call this the orthodox view. I argue that the orthodox view is false, and that a composite object is identical to the objects that compose it (collectively). This view is known as composition as identity. -/- I argue that, despite its unpopularity, there are many reasons to favour com- position as identity over the orthodox view. (...) First, defenders of the orthodox view have not offered complete theories of composition. For instance, they have not given adequate accounts of heterogeneous properties like being black and white in composite objects. Nor have they given satisfactory explanations for the necessary connections that hold between composite objects and their proper parts. -/- Second, there appears to be no good way for defenders of the orthodox view to remedy this. Any account of the heterogeneous properties of composite objects which is compatible with the orthodox view faces serious problems, as does any account of the necessary connections between an object and its proper parts. Composition as identity, on the other hand, is compatible with intuitive responses to both of these challenges. -/- Third, there are a number of strong arguments in favour of composition as identity. For example, composition as identity fits our evidence about the way the world is better than the orthodox view does. It also allows us to easily maintain that composition sometimes occurs and sometimes does not—i.e., it allows us to easily maintain that composition is restricted. The orthodox view does not. The theories of composition put forward by most philosophers are at best incomplete or in need of improvement. At worst, they are false and composition as identity is true. (shrink)

The Lewis-Sider argument from vagueness is one of the most powerful objections against restricted composition. Many have resisted the argument by rejecting its key premise, namely that existence is not vague. In this paper, I argue that this strategy is ineffective as a response to vagueness-based objections against restricted composition. To that end, I formulate a new argument against restricted composition: the argument from determinate vagueness. Unlike the Lewis-Sider argument, my argument doesn’t require accepting that existence is not vague, but (...) only that it is not vague in a specific way, which, I argue, is entailed by restricted composition. I show that the rejection of this species of vague existence follows from assumptions even friends of vague existence should be happy to accept. (shrink)

Unger’s Problem of the Many seems to show that the familiar macroscopic world is much stranger than it appears. From plausible theses about the boundaries of or- dinary objects, Unger drew the conclusion that wherever there seems to be just one cat, cloud, table, human, or thinker, really there are many millions; and likewise for any other familiar kind of individual. In Lewis’s hands, this puzzle was subtly altered by an appeal to vagueness or indeterminacy about the the boundaries of (...) ordinary objects. This thesis examines the relation between these puzzles, and also to the phenomenon of vagueness. Chapter 1 begins by distinguishing Unger’s puzzle of too many candidates from Lewis’s puzzle of borderline, or vague, candidates. We show that, contra Unger, the question of whether this is a genuine, as opposed to merely apparent, distinction cannot be settled without investigation into the nature of vagueness. Chapter 2 begins this investigation by developing a broadly supervaluationist account of vague- ness that is immune to the standard objections. This account is applied to Unger’s and Lewis’s puzzles in chapters 3 and 4. Chapter 3 shows that, despite its popularity, Lewis’s own approach to the puzzles is unsatisfactory: it does not so much solve the puzzle, as prevent us from expressing them; it cannot be extended to objects that self-refer; it is committed to objectionable theses about temporal and modal metaphysics and semantics. Chapter 4 develops a conception of ordinary objects that emphasises the role of identity conditions and change, and uses it to resolve both Problems of the Many. This allows us to diagnose the source of the puzzles: an overemphasis on mereology in contemporary material ontology. (shrink)

One of the standard puzzles in ordinary-object metaphysics concerns what happens when an object and one of its undetached parts apparently begin to coincide. I distinguish two versions of this puzzle: the problem of extraordinary undetached parts and the problem of ordinary undetached parts. Then I present a novel phasalist solution to the problem of ordinary undetached parts. My solution is designed to supplement the recently-defended view that ordinary undetached parts exist but extraordinary ones do not.

An important divide in the free will literature—one that is arguably almost as common as the distinction between compatibilism and incompatibilism—concerns the distinction between event and substance causation. As the story typically goes, event-causalists maintain that an action is free only if it is caused by appropriate mental events, and agent-causalists maintain that an action is free only if it is caused directly by a substance (the agent). This paper argues that this dichotomy is a false one. It does this (...) by introducing a new view called Causal Pluralism, which maintains that free will is compatible with both event and substance causation. Furthermore, it is argued that agent-causalists have good reason to adopt Causal Pluralism, and also that that the view has interesting implications for the free will dialectic. (shrink)

This paper proposes and examines an answer to the special composition question—complex objects compress information about their parts. I start by defending fastenation for material objects and then extract from fastenation the idea that the conjoinment of parts establishes correlations among the locations and motions of those parts. I move from this to the proposal that entities are parts of some object when that object allows for the efficient, if lossy, compression of information about those parts.

I argue that the growing-block theory of time and truthmaker maximalism jointly entail that some truthmakers undergo mereological change as time passes. Central to my argument is a grounding-based account of what I call the “purely incremental” nature of the growing-block theory of time. As I will show, the argument presented in this paper suggests that growing-block theorists endorsing truthmaker maximalism have reasons to take composition to be restricted and the “block” of reality to literally grow as time goes by.

The thesis of Weak Unrestricted Composition says that every pair of objects has a fusion. This thesis has been argued by Contessa and Smith to be compatible with the world being junky and hence to evade an argument against the necessity of Strong Unrestricted Composition proposed by Bohn. However, neither Weak Unrestricted Composition alone nor the different variants of it that have been proposed in the literature can provide us with a satisfying answer to the special composition question, or so (...) we will argue. We will then go on to explore an alternative family of purely mereological rules in the vicinity of Weak Unrestricted Composition, Cardinal Composition: A plurality of pairwise non-overlapping objects composes an object iff the objects in the plurality are of cardinality smaller than $$\kappa $$ κ. As we will show, all the instances for infinite $$\kappa $$ κ s determine fusion and are compatible with junk, and every instance for a $$\kappa > \aleph _0$$ κ > ℵ 0 is furthermore compatible with gunk and dense chains of parthood. (shrink)

It is widely assumed that if ontological disputes turn out to be verbal they ought to be dismissed. I dissociate the semantic question concerning the verbalness of ontological disputes from the pragmatic question on whether they ought to be dismissed. I argue that in the context of ontological disputes ontologists ought to be taken to communicate views with conflicting ontological commitments even if it turns out that on the correct view of semantics they fail to literally-express their disagreement. I argue, (...) that is, against dismissing ontological disputes on grounds of verbalness. This serves to discharge the ongoing debate on the verbalness of ontological disputes from the metaontological consequences typically associated with it. (shrink)

It is widely believed that deflationary truth has no explanatory power. I will argue that it does. Specifically, I will consider some objections to deflationary truth having explanatory power, and argue that they fail. The position which will emerge is that the deflationary concept of truth is analogous to the concept of an average. Scientists take averages to be explanatory, and I will argue that the concept of deflationary truth is explanatory in the same way. I then argue that this (...) deflationary _concept_ of truth motivates a theory of the _property_ of truth which is metaphysically disunified, but that this is no obstacle to explanation. This leads to a way of understanding the deflationary/substantive distinction in terms of grounding. (shrink)

The Monster Objection has often been considered one of the main reasons to explore non-standard mereological views, such as hylomorphism. Still, it has been rarely discussed and then only in a cursory fashion. This paper fills this gap by offering the first thorough assessment of the objection. It argues that different metaphysical stances, such as presentism and three- and four-dimensionalism, provide different ways of undermining the objection.

A fundamental fact is “pure” just in case it has no grounded entities—ex. Tokyo, President Biden, the River Nile, {Socrates}, etc.—among its constituents. Purity is the thesis that every fundamental fact is pure. I argue that Purity is false. My argument begins with a familiar conditional: if Purity is true, then there are no fundamental “grounding facts” or facts about what grounds what. This conditional is accepted by virtually all of Purity’s defenders. However, I argue that it is also the (...) first step toward Purity’s undoing. For, if every grounding fact has a ground, then some grounded entities have “groundmates” or distinct grounded entities that share their full grounds. But, if there are groundmates, then Purity is false. So Purity leads to a contradiction. Therefore, it is false. I close by noting that my argument against Purity also gives us a powerful reason to think that some grounding facts are fundamental. (shrink)