DISPOSITIONAL ONTOLOGY AS A BASIS FOR STRUCTURAL REALISM

In the last several decades, philosophers of biology have published countless books and articles on the causal mechanisms underlying evolutionary change. There has been scant effort devoted, however, to detailed analysis of what these mechanisms mean for the relationship between our best interpretations of evolutionary change and our metaphysical picture of the world. This thesis addresses some key aspects of that metaphysical picture. I argue for a metaphysically realist interpretation of dispositions as causally active in evolutionary biology. I address fitness and evolvability in particular, as they present two of the best possible case studies for a metaphysically realist interpretation of dispositions. I claim that dispositional realism is justified in part based on its empirical warrant. That is, as a metaphysics of science, it gives us all the metaphysics we need for making sense of the empirical success of science (especially biology), and no more. I present Ontic Structural Realism as an opposing view. Ontic Structural Realism argues for the dismissal of objects and dispositions on the basis of a certain interpretation of fundamental physics. I present some arguments against this view and in favor of my own.

This paper continues the analysis of the advantages and disadvantages of ontic structural realism, which begun in the first part of the paper. Non-eliminative versions of this approach are considered, which try to find a compromise between the ontology of structures and the ontology of objects. It is shown that the semirealism of A. Chakravartti and the constructive structural realism of T. Cao have a number of limitations caused by the authors’ desire to strictly distinguish between the nature of the existence of objects and structures. Then the version of the relationship between structures and entities is presented. Firstly, two concepts are divided according to their content: “object” and “entity”. Second, to solve the problem of causality, I suggest that the nature of entities and structures lie in their ability to act. It is this ability that I propose to use instead of the popular concepts of “causal powers”, “causal properties” or “dispositions”. Third, instead of a rigid alternative to ontological primitives – either essence, or causal relations, or structures – the concept of ontological pluralism and inherited existence is proposed. There each entity is represented as a derivative of another structure and, in turn, creates other entities and structures. Thus, both structures and entities at each level of the complexity hierarchy partially inherit the ability to act and a certain degree of existence from the structures and entities of the previous levels. Finally, I am trying to clarify the modal aspects of the ontic structural realism. Following the popular interpretations of quantum theory, the ability to act, and hence the existence of structures and entities, are considered separately in two worlds – potential and actual ones. The potential world is associated with a set of possible objects and structures of quantum theory, and the actual world is associated with a set of real (observable) objects and structures of classical physical theories. The transition from the potential to the actual world is proposed to be considered as a primitive metaphysical event. The proposed concept partially overcomes the objections to ontic structural realism, thereby strengthening its position in the discussion about the reality of quantum objects.

This paper continues the analysis of the advantages and disadvantages of ontic structural realism, which begun in the first part of the paper. Non-eliminative versions of this approach are considered, which try to find a compromise between the ontology of structures and the ontology of objects. It is shown that the semirealism of A. Chakravartti and the constructive structural realism of T. Cao have a number of limitations caused by the authors’ desire to strictly distinguish between the nature of the existence of objects and structures. Then the version of the relationship between structures and entities is presented. Firstly, two concepts are divided according to their content: “object” and “entity”. Second, to solve the problem of causality, I suggest that the nature of entities and structures lie in their ability to act. It is this ability that I propose to use instead of the popular concepts of “causal powers”, “causal properties” or “dispositions”. Third, instead of a rigid alternative to ontological primitives – either essence, or causal relations, or structures – the concept of ontological pluralism and inherited existence is proposed. There each entity is represented as a derivative of another structure and, in turn, creates other entities and structures. Thus, both structures and entities at each level of the complexity hierarchy partially inherit the ability to act and a certain degree of existence from the structures and entities of the previous levels. Finally, I am trying to clarify the modal aspects of the ontic structural realism. Following the popular interpretations of quantum theory, the ability to act, and hence the existence of structures and entities, are considered separately in two worlds – potential and actual ones. The potential world is associated with a set of possible objects and structures of quantum theory, and the actual world is associated with a set of real (observable) objects and structures of classical physical theories. The transition from the potential to the actual world is proposed to be considered as a primitive metaphysical event. The proposed concept partially overcomes the objections to ontic structural realism, thereby strengthening its position in the discussion about the reality of quantum objects.

The aim of this paper is to revisit the phlogiston theory to see what can be learned from it about the relationship between scientific realism, approximate truth and successful reference. It is argued that phlogiston theory did to some extent correctly describe the causal or nomological structure of the world, and that some of its central terms can be regarded as referring. However, it is concluded that the issue of whether or not theoretical terms successfully refer is not the key to formulating the appropriate form of scientific realism in response to arguments from theory change, and that the case of phlogiston theory is shown to be readily accommodated by ontic structural realism.

Ladyman and Ross (LR) argue that quantum objects are not individuals (or are at most weakly discernible individuals) and use this idea to ground their metaphysical view, ontic structural realism, according to which relational structures are primary to things. LR acknowledge that there is a version of quantum theory, namely the Bohm theory (BT), according to which particles do have definite trajectories at all times. However, LR interpret the research by Brown {\em et al.} as implying that "raw stuff" or {\em haecceities} are needed for the individuality of particles of BT, and LR dismiss this as idle metaphysics. In this paper we note that Brown {\em et al.}'s research does not imply that {\em haecceities} are needed. Thus BT remains as a genuine option for those who seek to understand quantum particles as individuals. However, we go on to discuss some problems with BT which led Bohm and Hiley to modify it. This modified version underlines that, due to features such as context-dependence and non-locality, Bohmian particles have a very limited autonomy in situations where quantum effects are non-negligible. So while BT restores the possibility of quantum individuals, it also underlines the primacy of the whole over the autonomy of the parts. The later sections of the paper also examine the Bohm theory in the general mathematical context of symplectic geometry. This provides yet another way of understanding the subtle, holistic and dynamic nature of Bohmian individuals. We finally briefly consider Bohm's other main line of research, the "implicate order", which is in some ways similar to LR's structural realism.

The focus of the paper is a discussion around one of the versions of scientific realism – ontic structural realism (OSR), which has gained popularity due to the development of quantum field theory. According to OSR, individual objects do not exist as ontological primitives. The ontology of objects and their properties is replaced by the ontology of structures and relations. The paper discusses the arguments of the proponents of OSR, describing it as the only way to preserve scientific realism in general relativity and in quantum physics, which are reduced to mathematical structures with different symmetries. Five possible variants of the ontological relationship between structures and objects are analyzed in detail. Particular attention is paid to the eliminative and non-eliminative versions of OSR. If the former in principle excludes any existence of objects, then in the latter, objects receive their secondary existence due to relations, and their identity is reduced to nodes in the structures of relations. The main objections to OSR and the answers of its proponents are analyzed. It is shown that references to quantum physics are both its strengths and weaknesses of OSR, since they often superficially refer to the formalism of the theory, not accepting one or another of its interpretation. The paper argues the thesis that the extreme eliminative OSR, despite all its advantages (it removes a few objections to scientific realism and offers a good explanation of modern physical theories), has several serious limitations. The best way out of the situation may be the development of the non-eliminative versions of OSR. In conclusion, it provides a critical analysis of one of these versions – moderate OSR of M. Esfeld and V. Lam, who believe that structures should have causal properties, something resembling a disposition.

Structural realism has recently re‐entered mainstream discussions in the philosophy of science. The central notion of structure, however, is contested by both advocates and critics. This paper briefly reviews currently prominent structuralist accounts en route to proposing a metaphysics of structure that is capable of supporting the epistemic aspirations of realists, and that is immune to the charge most commonly levelled against structuralism. This account provides an alternative to the existing epistemic and ontic forms of the position, incorporating elements of both. Structures are here identified with relations between first order, causal properties: properties that confer specific dispositions for relations. This form of structuralism constitutes an explicit proposal for what seem implicit structuralist tendencies in sophisticated but more traditional characterizations of realism. An outline of the proposal's response to the anti‐realist's pessimistic induction on the history of scientific theories is considered.

How can we account for the brain’s existence and reality? I now shift my focus from the empirical (Part I and II) context in the previous chapters to the ontological dimension. Specifically, I focus on an “ontology of brain” as part of a wider “philosophy of brain” (Northoff 2004). Based on the empirical data, I argue that the brain’s existence and reality is based on structure and relation rather than elements like properties. This makes possible to determine the brain’s existence and reality by world-brain relation rather than physical or mental properties within the brain itself. That is well compatible with ontic structural realism (OSR). More specifically, the world-brain relation can be understood in spatiotemporal terms entailing what I describe as “spatiotemporal ontology”. Time and space are here no longer understood in observational terms, e.g., “observational time and space”, but rather as relational in the sense of OSR, i.e., “relational time and space”. Taken together, I ontologically characterize the brain by world-brain relation presupposing relation and structure as in OSR. This amounts to a “relational view” of the brain in our “ontology of brain”. Such relational view of the brain’s existence and reality can be specified by “relational time and space” (as I say) as distinguished from “observational time and space”. That opens the door for a novel ontological characterization of consciousness in the terms of world-brain relation and OSR – this shall be the focus in the next chapter.

Ontic structural realism and quantum field theory: Are there intrinsic properties at the most fundamental level of reality?

Various forms of underdetermination that might threaten the realist stance are examined. That which holds between different ‘formulations’ of a theory (such as the Hamiltonian and Lagrangian formulations of classical mechanics) is considered in some detail, as is the ‘metaphysical’ underdetermination invoked to support ‘ontic structural realism’. The problematic roles of heuristic fruitfulness and surplus structure in attempts to break these forms of underdetermination are discussed and an approach emphasizing the relevant structural commonalities is defended.

The ‘underdetermination of metaphysics by the physics’ is the thesis that our best scientific theories do not uniquely determine their ontologies. Nonrelativistic quantum mechanics is famously thought to exemplify this kind of underdetermination: it may be seen as compatible with both an ontology of individual objects and with an ontology of non-individual objects. A possible way out of the dilema thus created consists in adopting some version of Ontic Structural Realism (OSR), a view according to which the metaphysically relevant aspect of the theory is its structure, not the nature of the objects dealt with. According to OSR, particular objects may be dispensed with (eliminated or re-conceptualized) in favor of the structure of the theory. In this paper we shall argue that the underdetermination of metaphysics by the physics is a consequence of a too strict naturalism in ontology. As a result, when a mitigated ontological naturalism is taken into account, underdetermination does not appear to have such dark consequences for object-oriented ontologies in quantum mechanics.

In quantum mechanics, entangled states are not exotic or rare. Rather, entanglement is the norm and so the metaphysical consequences of entanglement are a central issue for anyone wishing to provide an ontological interpretation of the various formulations of quantum mechanics. This chapter presents the argument for wave function realism from quantum entanglement, which says that wave function realism is necessary if one wants an ontological interpretation that does not conflate distinct quantum states. It explains quantum entanglement and how postulating a wave function in higher dimensions can help to metaphysically ground the phenomenon. The chapter ultimately concludes that the argument from quantum entanglement fails as there are several rival positions that can also explain quantum entanglement and recover the distinctions between different entangled states. These include the primitive ontology approach, various other holisms, ontic structural realism, spacetime state realism, and the multi-field approach.

In this chapter the investigation moves towards metaphysics and speculation. At this point a first attempt to answer the question of what is real using the hallmark feature introduced in the last chapter (real is what resists) is made. This first attempt to answer what is real uses physicalist, naturalist and materialist approaches to understand the real. After discussing traditional forms of naturalism and materialism and presenting, their respective problems in accounting for the dynamic and relational aspects of reality are introduced. Thus, more dynamic and relational forms of naturalism or physicalism are presented, namely ontic structural realism (Ladyman and Ross) and transcendental scientific realism (Sellars). Both positions are better able to come to terms with the dynamic, networked reality that we are living in, but still fail to fully account for its integrated and temporal nature.

There is good reason to believe that scientific realism requires a commitment to the objective modal structure of the physical world. Causality, equilibrium, laws of nature, and probability all feature prominently in scientific theory and explanation, and each one is a modal notion. If we are committed to the content of our best scientific theories, we must accept the modal nature of the physical world. But what does the scientific realist’s commitment to physical modality require? We consider whether scientific realism is compatible with Humeanism about the laws of nature, and we conclude that it is not. We specifically identify three major problems for the best-systems account of lawhood: its central concept of strength cannot be formulated non-circularly, it cannot offer a satisfactory account of the laws of the special sciences, and it can offer no explanation of the success of inductive inference. In addition, Humeanism fails to be naturalistically motivated. For these reasons, we conclude that the scientific realist must embrace natural necessity.

Russellian monism—an influential doctrine proposed by Russell (The analysis of matter, Routledge, London, 1927/1992)—is roughly the view that physics can only ever tell us about the causal, dispositional, and structural properties of physical entities and not their categorical (or intrinsic) properties, whereas our qualia are constituted by those categorical properties. In this paper, I will discuss the relation between Russellian monism and a seminal paradox facing epiphenomenalism, the paradox of phenomenal judgment: if epiphenomenalism is true—qualia are causally inefficacious—then any judgment concerning qualia, including epiphenomenalism itself, cannot be caused by qualia. For many writers, including Hawthorne (Philos Perspect 15:361–378, 2001), Smart (J Conscious Stud 11(2):41–50, 2004), and Braddon-Mitchell and Jackson (The philosophy of mind and cognition, Blackwell, Malden, 2007), Russellian monism faces the same paradox as epiphenomenalism does. I will assess Chalmers’s (The conscious mind: in search of a fundamental theory. Oxford University Press, New York, 1996) and Seager’s (in: Beckermann A, McLaughlin BP (eds) The Oxford handbook of philosophy of mind. Oxford University Press, New York, 2009) defences of Russellian monism against the paradox, and will put forward a novel argument against those defences.