Tomasz Bigaj Van Inwagen and the Polish Logician

In his 2002 paper “ “Carnap” and “the Polish Logician” ” Professor Peter van Inwagen criticizes Hilary Putnam’s argument for the claim that there is no fact of the matter as to how many objects there are. Putnam’s argument relies on the comparison between two alternative metaphysical views (ascribed, respectively, to “Carnap” and “the Polish Logician”) regarding the existence of mereological compositions of objects. “Carnap’s view” describes a given world as containing exactly three simple (i.e. having no proper parts) objects, while “the Polish Logician’s view” adds to the list of objects all mereological sums of these simples.  Van Inwagen rejects Putnam’s contention that these views are “equally good” descriptions of a certain world, arguing that they are plainly incompatible and thus cannot be jointly true. Moreover, van Inwagen rejects the view, based on Mereology, that arbitrary objects always compose greater wholes. In my talk I would like to discuss a possible response that the Polish Logician (modeled on Stanisław Leśniewski) might have to van Inwagen’s position on this issue. My aim is to show that it is possible to retain Mereology and its commitment to arbitrary collections of objects while respecting the key intuitions that led van Inwagen and other philosophers to the rejection of the mereological principle of unrestricted composition.

Andrea BottaniVan Inwagen on Properties, Nominalism and Things That Can Be Said

In his ‘A theory of Properties’, Peter van Inwagen argues that properties are unsaturated assertibles, i.e., things that can be said of things. This idea, he says, ‘is very nearly vacuous’, but its consequences are substantial and fundamental. If properties are things that can be said of things, he argues, they are abstract and universal; they necessarily exist; they are related to things that have them, but are not their constituents; they can be actually and even necessarily uninstantiated; they are abundant and not sparse; they cannot be objects of sensation; and, finally, in no way are they more fundamental than the things that have them. All these theses are controversial, even though some of them may be more controversial than others. Here I confine myself to arguing against the less controversial, perhaps, of them all. I claim that properties might be non-universal – and, at least in some sense, non-abstract – even if they were things that can be said of things. What I try to argue, more precisely, is that treating having as location, properties as places, and using geometry in place of set theory, is in principle able to reconcile austere nominalism with the purported role of properties as unsaturated assertibles.

Chris DalyVan Inwagen on Testimony and Contingency

This paper concerns two issues about rational belief revision that are drawn from Peter van Inwagen’s work. First, the argument from philosophical testimony. Suppose you think that some philosophical argument A is sound; suppose you then discover that David Lewis rejects A as unsound; Lewis is a far more expert philosopher than you; so what should your degree of belief that A is sound now be? Second, the argument from contingency. Very many of your philosophical beliefs have formed been through chance matters — what you have read, what you haven’t read, who you happened to have discussed matters with, and so forth. Given this contingency, what should your degrees of belief about philosophical matters be?

Mario De Caro Free Will after Van Inwagen

In the last decades, Peter van Inwagen’s contributions have dramatically changed the terms of the discussion on free will. Nowadays, advocates of all the conceptions have to deal with van Inwagen’s sharp critical arguments and with his bewildering conclusion that free will is, at the same time, indispensable and impossible.
In my paper I will discuss the challenges and the prospects that the different views of freedom face in light of van Inwagen’s groundbreaking contributions.

Rafał GruszczyńskiAn Argument for the Existence of Arbitrary Mereological Sums

Leśniewski’s mereology is mathematical theory of objects and their parts. Conceived by the Polish logician as would-be replacement of Cantorian set theory as a foundation of mathematics, it has never fulfilled this task, yet it has become a theoretical framework for metaphysical analysis of the world in terms of parthood relation. The key notion of mereology is that of mereological sum (or mereological fusion). The principle of existence of mereological sums says, in one of its milder forms, that to every pair of object s corresponds the object which is composed from them and nothing more. The problem addressed by Van Inwagen in Material Beings (1990) as special composition question may be shortly summed up in the following way: what does it take for a group of objects to have a mereological sum? Can we really adopt the mereological sum principle as a metaphysical law of the reality? In my presentation, via constructing a mereological interpretation of Gallileo’s reasoning which led to the conclusion that the acceleration of free falling bodies is independent from their mass, I would like to show that the only reasonable solution is to accept the principle of existence of mereological sums for arbitrary groups of objects. That is, my aim is to formulate an argument which shows that to reach his conclusion, the Italian astronomer must have used a pre-theoretical and intuitive notion of mereological sum along with tacit assumption of the aforementioned principle. If the reasoning which led to formulation of one of the key principles of physics requires both the notion and the principle, it seems reasonable to treat them as something more than only theoretical curiosity.
The presentation is a development of my talk which I gave at the Contemporary Polish Ontology workshop in Warsaw (2016) under the title Mereology and Galileo’s reasoning and contains new results and improvements of the material presented at the event.

William JaworskiThe Closet Hylomorphist?

Peter van Inwagen is well known for his groundbreaking work on composition. Less well known is the way that work has contributed to the rehabilitation of hylomorphism, the view that some individuals—paradigmatically living things—are composed of physical materials with a specific organization or structure. I explain how van Inwagen’s ideas provide the basis for a hylomorphic theory that dovetails with current work in biology and biological subdisciplines such as neuroscience. That theory differs from van Inwagen’s in an important respect: it is committed to the existence of functional parts such as eyes, hearts, and brains. I argue that this commitment is a straightforward implication of van Inwagen’s claim that the details about what lives are and what characteristics they have need to be supplied empirically, for actual empirical work on living things posits functional parts. I defend this implication against its detractors, and argue that a commitment to functional parts enables hylomorphists to respond more effectively to the objections that have been levied against van Inwagen’s own view.

Christian KanzianParaphrase: A (More or Less) Van Inwagenian Way to (Moderate) Nominalism

“It would be better not to believe in abstract objects if we could get away with it” is the heading of the first section of chapter 8 (A theory of properties) of Peter Van Inwagen’s book Existence (Cambridge University Press 2014). In my talk I intend to work on the if-clause in order to make clear that it is actually possible to avoid Platonism, at least to a remarkable extent. (I am more optimistic than Van Inwagen seems to be.)
My main concern are abstract natural kinds, respectively a paraphrase of sentences in which we (seemingly) commit ourselves to such kinds. The paraphrase which I suggest relies on an ideological (Quine) tool-box of primitive concepts, which also allow reducing property-universals. The nominalism I have in mind is nevertheless moderate, since it does not pretend to get away with all abstracta. Mathematical objects are excluded from my anti-platonistic attempts.
In order to reach my goal I will deal with the topic “paraphrase” in general, provide criteria for the success of paraphrases and reflect on the theoretical presuppositions of the suggested paraphrase.

Zbigniew Król & Józef LubaczMetaphysics of Existential Quantification. Is Analytical Philosophy the Future of Metaphysics?

We discuss relations between ontological existence and existential quantification in the context of the ontological commitments of discourses and theories. In particular, we refer to the problem of monism and pluralism and to the questions arising from the differentiation between being and beings. The discussion indicates some possible lines of the development of ontology and is not limited to the analytical perspective.

Hannes LeitgebMetaphysics as Rational Reconstruction

I will defend a metaphilosophical proposal to the effect that philosophy ought to be viewed as the discipline of rational reconstruction. In a nutshell, rationally reconstructing a cultural product X (a concept, an argument, a belief, a method, an ideal,…) means: X is made transparent, precisified, and systematized; on that basis, X’s rationality or irrationality features are determined and assessed; in this way, one gets rational control over X; and finally—when necessary—one improves X by transforming it into a more rational X’. One consequence of this normative and pragmatic account of philosophy as “rationality engineering” is that philosophy differs from science, and hence certain versions of naturalism about philosophy are wrong. For the same reason, the view also leads to a worry about metaphysics: if metaphysics were to aim at a high-level description of the world, it would belongs to science, not to philosophy qua rational reconstruction. I will suggest a way out of this problem by proposing to view metaphysics as the philosophical discipline devoted to the rational reconstruction of conceptual frameworks. This amounts to a more fruitful way forward for metaphysics, as I am going to argue by means of some examples. And metaphysics in this sense is perfectly compatible with an enlightened logical-mathematical empiricism.

Øystein LinneboGenerality Explained: a Truth-Maker Semantics

What explains a true universal generalization? This paper distinguishes and investigates between two kinds of explanation. While an instance-based explanation proceeds via each instance of the generalization, a generic explanation is independent of each instance, relying instead on completely general facts about the properties or operations involved in the generalization. This distinction is illuminated by means of a truth-maker semantics, which is also used to show that instance-based explanations support classical logic, while generic explanations support only support intuitionistic logic.

Øystein Linnebo and Stewart ShapiroPotential Infinity: a modal account

Beginning with Aristotle, almost every major philosopher and mathematician before the nineteenth century rejected the notion of the actual infinite. They all argued that the only sensible notion is that of potential infinity. The list includes some of the greatest mathematical minds ever. Due to Georg Cantorís ináuence, the situation is almost the opposite nowadays (with some intuitionists as notable exceptions). The received view is that the notion of a merely potential infinity is dubious: it can only be understood if there is an actual infinity that underlies it.
After a sketch of some of the history, our aim to analyze the notion of potential infinity, in modal terms, and to assess its scientific merits. This leads to a number of more specific questions. Perhaps the most pressing of these is whether the conception of potential infinity can be explicated in a way that is both interesting and substantially diferent from the now-dominant conception of actual infinity. One might suspect that, when metaphors and loose talk give way to precise definitions, the apparent diferences will evaporate.
As we will explain, however, a number of diferences still remain. Some of the most interesting and surprising diferences concern consequences that one’s conception of infinity has for higher-order logic. Another important question concerns the relation between potential infinity and mathematical intuitionism. We show that potential infinity is not inextricably tied to intuitionistic logic. There are interesting explications of potential infinity that underwrite classical logic, while still difering in important ways from actual infinity. However, we also find that on some more stringent explications, potential infinity does indeed lead to intuitionistic logic.

Anna-Sofia MaurinOn the Nature of Tropes

According to Van Inwagen (2011), a good taxonomy of ontologies is one which distinguishes between, on the one hand, the mono- and the polycategorical and, on the other hand, the relational and the constitutive. Van Inwagen defends a polycategorical relational ontology (although he admits that, were it possible, he would prefer a one-categorical version of the same view). Polycategorical constitutive ontologies (such as Armstrong’s theory of immanent universals, or Lowe’s four-categoricalism) he finds incomprehensible. Mono-categorical constitutive theories like e.g., Laurie Paul’s mereological bundle theory he seems to find slightly more palatable, although still irredeemably flawed. Van Inwagen’s complaints are many and varied. Here I want to focus on investigating one of the things he seems to think all of these views – including Paul’s – accept, and which he finds problematic: the idea that properties are spatiotemporal (and so perceivable) entities. In my talk, I argue that on the best version of trope theory, tropes are not properties in this sense. Neither are they properties in Van Inwagen’s sense (i.e., non-spatiotemporal and abstract entities). Nor are they objects in the sense of ‘normal’ concrete particulars. Tropes are neither of these things, and therefore very well suited to constitute all of them. More precisely, my presentation investigates recent, as well as older, critique of the trope view, according to which its posit are trying to do two things at the same time – play the role of the particular and of the property – thereby either ending up in contradiction or, at least, failing miserably at either or both. I argue that this sort of critique is not successful and that this is in part due to the fact that the nature of the trope has been unfairly taken to belong to either the (traditional) property- or the (traditional) object-camp.

Kris McDaniel Van Inwagen and Being

Prof. van Inwagen defends the thesis that existence is univocal. In this talk, I will do the following things. First, I will try to clarify what van Inwagen means by “existence is univocal”. Second, I’ll discuss how van Inwagen reconciles the thesis that existence is univocal with the claim that all physical objects are mereological simples or living beings, but nonetheless ordinary people can truly say, “there are chairs”. Third, I’ll critically examine one of van Inwagen’s arguments for the thesis that existence is univocal. Finally, I will discuss a version of “anti-realism about ontology” that is not refuted by van Inwagen’s arguments for the thesis that existence is univocal.

Uwe Meixner Metaphysical Differences

Some of Peter van Inwagen’s metaphysical positions are compared with the positions of other metaphysicians – positions which are incompatible with van Inwagen’s. The question will be asked (and answered): What does this situation of conflict among metaphysicians tell us about the nature of metaphysics and, more generally, philosophy?

Friederike MoltmannNatural Language Ontology

It is generally agreed that natural language reflects its own ontology, ontological categories, notions, or structures, that may be different from the ones a philosopher may be willing to accept or a nonphilosopher when thinking about what there is and how things are. While there are philosophers that have made crucial appeal to natural language for the purpose of a metaphysical argument, the ontology of natural language is also the subject matter of a discipline, natural language ontology, as part of both linguistics and metaphysics. This talk, by discussing some central cases, aims to clarify a range of issues that arises for natural language ontology, such as what sorts of linguistic data reflect and what sorts of data do not reflect the ontology of language, how the ontology of language should itself be characterized, and how natural language ontology relates to other branches of metaphysics as well as linguistics.

Kevin Mulligan“Modes of Being” and the Mind

As Peter van Inwagen has shown, what have been called modes of being are not modes of being. What, then, are they and how do they relate to essence and the mind ? I consider and evaluate some answers, old and new, Continental and Analytic, to these and related questions.

Stephen D. Mumford In Defence of Free Will

Although Van Inwagen’s defence of incompatibilism concerning free will and determinism is correct, his classic framing of the problem presents us with a dilemma. If determinism is true, it looks like we have no free will; but if indeterminism is true, we don’t seem to have it either. Free will might then be incoherent, or perhaps be some brute but mysterious truth. In response, we assemble some of the elements required for a positive defence of free will. Many pre-existing discussions have concentrated on what must not be the case in order for us to have our freedom. But the ultimate acceptability of libertarianism will come down to what positive case can be made for it: describing the conditions that must be met for a being to be free, which then allows us to judge whether any meet those conditions. Accordingly, we offer a conceptual analysis of free will based on a proper account of emergent causal powers and their exercise, and conclude it is plausible that at least some beings meet the conditions of freedom.

Joanna Odrowąż-SypniewskaThe Problem of the Many and Ontic Vagueness

The problem of the many arises because of the following assumptions: (a) For many composite objects X there are objects y0, …., yn such that it is indeterminate whether they are part of X or not; (b) For each such object yi there is an object Zi which consists of yi and all the unquestionable parts of X; (c) Zi are so similar to X, that they should count as X. Since Peter van Inwagen in Material Beings argues that the only complex objects are animate objects, the problem of the many constitutes a puzzle for him only in the case in which living organisms are involved. And he solves the puzzle by rejecting the assumption (b), i.e. the very idea that motivates the problem: the idea that in fact there are many complex objects – many distinct sets of simples, the differences between which are negligible – in the place we thought was just one object. The object is just one: the fuzzy set whose members are parts of the complex object in question. Such a set is fuzzy because parthood is a vague relation and is just one because in every such situation there is only one life present. Thus, the problem of the many can be solved as long as one is prepared to acknowledge that there is vagueness in the world (which according to van Inwagen one should acknowledge anyway).
In my talk I’ll try to assess van Inwagen’s almost 30-year old solution from today’s viewpoint.

Francesco OriliaVan Inwagen’s Approach to Relations and the Theory of O-roles

In his 2006 paper “Names for Relations” Van Inwagen has tackled in his typically penetrating way some very important issues concerning relations. Over the years I myself have discussed relations in several occasions and have built up a theory based on the idea that there are ‘o-roles,’ namely ontological counterparts of the thematic roles typically appealed to in linguistics. In this paper I shall focus on the problems discussed by Van Inwagen in his 2006 paper and argue that they are best approached from the perspective of my o-roles theory. I shall then consider how o-roles could find a place within Van Inwagen’s general metaphysical perspective.

Carl PosyInside the Metaphysical Workshop

Adapting an expression of David Lewis’, van Inwagen speaks about the significance of our discourse “inside the ontology room”. I have modified this metaphor in order to emphasize that metaphysicians’ need to be mindful of the proper use of the tools of their profession. van Inwagen is highly attuned to this requirement, but, as I will note, it is sometimes tempting to be less disciplined.
My talk will have three parts. The first two explore the use and possible misuse of a particularly ubiquitous tool that comes from logic: recursive truth definitions. The third part expands that discussion speculatively to a more general view of metaphysical tools. Specifically:

  • In the first part of the talk, I will look at a straightforward generalization of standard model-theoretic semantics; and, by means of this revised semantic framework, I will compare the ways in which some modern and traditional metaphysicians use that logical tool. van Inwagen’s ideas about ontological categories as well as some recent work in meta-semantics will serve as background here.
  • In the second part, I will apply the revised semantic framework to expose an enticing metaphysical misuse of that tool: appealing to semantics and logical form, where in fact different tools (arguments from different philosophical spheres) are called for.
  • This, in turn, will lead me, in part three, to look generally at how distinct tools interact in the practice of metaphysics and to contrast this metaphysical synergy with its empirical counterpart. Here I will take my cue from van Inwagen’s remarks about how we must conduct our discourse when we are ‘inside’ versus when we are ‘outside’ the ontology room.

Gonzalo Rodriguez-PereyraMust the Probability of Nothing Existing Be 0?

In this paper I critically discuss Peter van Inwagen’s argument that a world with no concrete beings has probability 0 in his article ‘Why is there anything at all?’

Benjamin SchniederThe Relevance of Grounds

Reality may be understood as the totality of facts, though not as a mere aggregate of them. Instead, it should be conceived of a an ordered system of facts in which some facts make others obtain, so that the latter are grounded in others. A robust grasp of the pertinent notion of grounding, i.e. the relation between a ground and a grounded fact, therefore plays a pivotal role for metaphysical research.
In this talk, I want to argue that a clarification of the notion of grounding provides the means of criticizing two famous arguments defended by Peter van Inwagen: On the one hand, his “cosmological” argument against the Principle of Sufficient Reason, and on the other hand his Consequence Argument. Both arguments can be resisted on the basis of reflections on the nature of grounds and on structural features of the relation of grounding.

Gila SherMetaphysics and Human Cognition: A New Approach to a Classical Question

The question “How is philosophical knowledge possible?” is a classical philosophical question, and nowhere is it more poignant than with respect to metaphysics. Yet considerable progress has been made in this field in our time by Peter van Inwagen and others. In this talk I would like to explore this question from two directions: (1) Does the world (broadly understood) have metaphysical features, or in other words, is there any real thing for metaphysics to provide knowledge of? And (2): Do we, humans, have cognitive resources for accessing the metaphysical features of the world and providing veritable knowledge about them? I will offer a few new ideas about a possible approach to these questions.

Peter SimonsThe Concept of Organism and Degrees of Composition

The idea of composition – one thing’s being made up of several things – is age-old, but we owe focus on the question when things compose other things to Peter van Inwagen. Philosophers’ answers to this, his Special Composition Question, have been very varied. There are two extreme positions: nihilism and universalism. Nihilism says that nothing is ever composed of anything else, while universalism says that any things compose another thing. Both answers have been defended, and both fly in the face of common sense and much evidence from science. Intermediate positions however prove to be difficult to formulate and defend. Peter’s own intermediate position is towards the nihilistic end of the spectrum. According to it, the only cases of composition are when simples compose a living organism. While sharing many of the difficulties of nihilism, it faces its own special composition difficulty: what it is to be a single organism is vague. I adduce evidence from biology that what biologists (unhappily) call “organismicity” or “organismality” comes in degrees. It is clearest in the case of macroscopic animals, but becomes much murkier among the other biological kingdoms. Further, nearly all cases of major evolutionary advance have occurred through the coming together of previously independent individuals, from replicators to eukaryotic cells to multicellular organisms. Transitional cases therefore likewise stand in the way of a clear-cut criterion of composition. I do not shrink from this vagueness – I welcome it, for it matches the evidence from other domains than the organic, that composition is not an all-or-nothing affair, and that what it is to count as a single, complex individual is not an exact matter. This is not a weakness of our conceptions or theories, but a feature of the world, and the sooner we work with rather than against it, the quicker our metaphysics of composition will recover and become relevant to real-world cases.

Alfredo TomasettaThe Vat Matters. A Defence of Animalism from the Remnant-Person Problem

Peter Van Inwagen is among the main contemporary proponents of animalism, the view in personal ontology according to which we are identical to human animals. This paper focuses on a major objection to animalism put forward by Mark Johnston: the Remnant-Person Problem. Your brain detached from your skull and kept alive seems to be a person; now, if she is not you, then one can bring a person into being simply by removing tissue from something, and this is absurd; if, on the other hand, she is you, then animalism is false. Van Inwagen can offer a solution to this puzzle by denying the assumption that a detached brain is a person: I agree, but I claim that this can be done without assuming his well-known mereological theses.

Takashi YagisawaImagining Fictional Characters

Abstract artifactualism (AA) is the metaphysical theory that all fictional objects are abstract objects, actually created artificially by authors.
I wish to object to AA by strengthening the existing objection targeting the abstractness AA attributes to fictional objects. The objection concerns the fact of our imaginative engagement with fictional objects in general, and fictional characters in particular. When we read a work of ordinary narrative fiction, we imagine the fictional characters that appear in the fiction. Our imagining the fictional character is almost always vital to our appreciation of the work as literature. But we cannot imagine abstract objects. Therefore, the fictional characters are not abstract.
This objection invites obvious counters on behalf of AA. Two of them rely on a distinction between different kinds of predication: the have/hold (or exemplify/encode) distinction, and the outside-the- story/according-to- the-story distinction. A third counter relies on a distinction between different kinds of use of language: the out-and- out use/pretended use distinction. I discuss these counters critically, focusing on the notion of imagination de re.

Key Words: fiction, abstract artifactualism, imagination, de re, predication, pretense

Dean ZimmermanVan Inwagen, Vagueness, and the Problem of No Best World

Peter van Inwagen argues that, because of the vagueness of the goods associated with human flourishing, gratuitous evils may well be necessary features of a world in which such goods occur. Van Inwagen’s conclusion conflicts with a principle advocated by William Rowe in his well-known argument that, if there is no maximum to the goodness of creatable worlds, God is impossible. But Rowe’s principle is suspect in any case. It is a kind of expression principle — in ideal circumstances, the precise degree of a certain character trait will be fully expressed in action. Such principles are dubious when agents confront decision problems involving infinities or a sorites series.