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.

This entry focuses on two of the more historically important monisms: existence monism and priority monism . Existence monism targets concrete objects and counts by tokens. This is the doctrine that exactly one concrete object exists. Priority monism also targets concrete objects, but counts by basic tokens. This is the doctrine that exactly one concrete object is basic, which will turn out to be the classical doctrine that the whole is prior to its parts.

Existence monism (EM) is a metaphysical view asserting the existence of only one concrete object. EM is well known for its radicalness, and encounters difficulty in terms of its prima facie inconsistency with truisms. This paper aims to propose an alternative (and somewhat easy) way to overcome this difficulty and indicate another means by which the possibility of EM can be defended. I will present a package of theses that are intended to be combined with EM, which I call Linguistic (...) Ontology with the One as Semantic Glue (LOOSG). I will show that this package (in combination with EM) provides a systematic explanation as to why truisms hold while only one concrete object actually exists. In other words, I will argue that if an existence monist embraces LOOSG, the desired explanation for truisms is then available to her. In addition, it will also be noted that LOOSG has a theoretical virtue, in that it only presupposes the framework of standard semantics. Based on these discussions, I offer LOOSG as a viable option for existence monism. (shrink)

Can the neo-Aristotelian uphold a pluralist substance ontology while taking seriously the recent arguments in favour of monism based on quantum holism and other arguments from quantum mechanics? In this article, Jonathan Schaffer’s priority monism will be the main target. It will be argued that the case from quantum mechanics in favour of priority monism does face some challenges. Moreover, if the neo-Aristotelian is willing to consider alternative ways to understand ‘substance’, there may yet be hope for a pluralist substance (...) ontology. A speculative case for such an ontology will be constructed based on primitive incompatibility. (shrink)

This thesis explores the possibility of composite consciousness: phenomenally conscious states belonging to a composite being in virtue of the consciousness of, and relations among, its parts. We have no trouble accepting that a composite being has physical properties entirely in virtue of the physical properties of, and relations among, its parts. But a long­standing intuition holds that consciousness is different: my consciousness cannot be understood as a complex of interacting component consciousnesses belonging to parts of me. I ask why: (...) what is it about consciousness that makes us think it so different from matter? And should we accept this apparent difference? (shrink)

According to “existence monism,” there is only one concrete particular, the cosmos as a whole (Horgan and Potrč 2000, 2008). According to “priority monism,” there are many concrete particulars, but all are ontologically dependent upon the cosmos as a whole, which accordingly is the only fundamental concrete particular (Schaffer 2010a, 2010b). In essence, the difference between them is that existence monism does not recognize any parts of the cosmos, whereas priority monism does – it just insists that the parts are (...) ontologically dependent upon the whole in this case. Brentano never maintained either of these views. But in the last two years of his life, he seems to have held the following approximation: there is only one physical substance, namely, the material universe as a whole. This is twice removed from existence or priority monism: first, it allows for a plurality of mental substances (souls); secondly, it allows for a plurality of physical accidents, which in Brentano’s reistic ontology are also concrete particulars. Still, the view that the only physical substance is the universe as a whole is quite radical and finds little precedent in the history of philosophy. (shrink)

Monism, characterized by Jonathan Schaffer as the thesis that the cosmos is the one and only basic actual concrete object, has been the subject of a great deal of recent interest. Spinoza is often taken, rightly, to be an important forebear. This article seeks to explain the distinctive content and basis of Spinoza’s monistic metaphysics and to compare it to contemporary Monism. It then argues that although Spinoza’s monistic metaphysics is not strictly a version of Monism as defined, it has (...) a number of theoretical advantages that make central aspects of it worthy of serious consideration. (shrink)

Schaffer offers us in the last section of “On What Grounds What” (2009) an applied illustration of his allegedly Aristotelian metaontological position. According to this illustration, Schaffer’s metaontological position, supplemented with a few Aristotelian theses about substance and grounding, would converge in a view remarkably similar to his priority monism (Philosophical Studies, 145, 131–148, 2009b; Philosophical Review, 119, 31–76, 2010a), the view that there is one single fundamental substance. In this paper, I will argue against Schaffer’s suggestion that priority monism (...) represents a viable development of Aristotelian metaphysics. In particular, I will hold that the most plausible version of Schaffer’s priority monism by Aristotelian standards fails to satisfy basic Aristotelian tenets about dependence, composition, change, and persistence, and suggest that this is evidence that Aristotelians are more at home with a pluralism rather than a monism about substance. (shrink)

Monism is the view that there is only a single material object in existence: the world. According to this view, therefore, the ordinary objects of common sense—cats and hats, cars and stars, and so on—do not actually exist; there is only the world. Because of this, monism is routinely dismissed in the contemporary literature as being absurd and obviously false. It is simply obvious that there is a plurality of material things, thus it is simply obvious that monism is false, (...) or so the argument goes. I call this the common sense argument against monism and in this paper I offer a response. I argue that providing the monist can make his view consistent with the appearance that there is a multiplicity of material things, then it is not rationally acceptable to reject monism solely on the basis of that appearance. Through an appeal to a particular type of property—distributional properties—I sketch out a plausible story of how monism is perfectly consistent with the appearance of plurality, and thus nullify the common sense argument. There may be any number of arguments that serve to undermine monism, but the common sense argument is not one of them. Monism deserves to be taken more seriously than that. (shrink)