The concept of possible worlds is useful because it defines the four modalities – possibility, necessity, contingency, and impossibility – but a challenge lies in defining it. The polemical hypothesis from David Lewis (“genuine modal realism“ as it is called) succeeds in it. Lewis’ modal realism stirred controversy because he maintains that a plurality of worlds exists. Some philosophers suggest that the Lewisian view is a violation to the law of parsimony, also known as Ockham’s Razor, that is to say not multiply entities beyond necessity.
While avoiding a circular definition, Lewis constructs an inflated ontology. Is it worth it, and if we do not want to assume too many Lewisian worlds, what alternatives remain? Actualist modal realism and modal antirealism are the most relevant alternatives because modal abstentionism simply will not progress in this direction. This thesis evaluates theories of possible worlds.
Table of Contents
1. Modalities
1.1 Possibility
1.2 Contingency
1.3 Necessity
1.4 Impossibility
2. Modal Logic
2.1 What is Modal Logic?
2.2 Possible Worlds Semantics
3. Theories of Possible Worlds
3.1 Modal Realism
3.2 Actualist Modal Realism
3.2.1 Plantingan Modal Realism
3.2.2 Combinatorialism
3.2.3 Nature Modal Realism
3.2.4 Book Modal Realism
3.3 Concreteness or abstractness?
3.4 Genuine Modal Realism
3.4.1 Lewis’ Analysis of Possible Worlds.
3.4.2 Counterpart Theory
3.4.3 Arguments in Favour of Genuine Modal Realism
3.5 Critique of Genuine Modal Realism
3.6 Neo-Meinongianism
3.6.1 Meinongian Modal Realism
3.7 Hybrid Modal Realism
4. Evaluation
5. Summary
6. Final Thoughts
Objectives and Topics
This thesis aims to evaluate different theories regarding the concept of possible worlds, specifically addressing the philosophical challenges of defining modal concepts and the ontological status of these worlds. The author investigates whether possible worlds are concrete entities, as argued by David Lewis, or abstract structures, and examines the viability of reducing modal statements to non-modal terms.
- The distinction and interrelation of the four modalities: possibility, necessity, contingency, and impossibility.
- An assessment of Modal Realism, including the differences between "genuine" (Lewisian) and "actualist" modal realism.
- A critical analysis of the ontological status of possible worlds and the problem of concrete versus abstract entities.
- The application of "counterpart theory" as a solution to the challenges of de dicto and de re modal statements.
- The evaluation of Neo-Meinongianism and hybrid approaches to handle impossible worlds and inconsistent propositions.
Excerpt from the Book
3.4.3 Arguments in Favour of Genuine Modal Realism
The world could be different than it is; it could end tomorrow or it could be a better place. We are faced with choices in everyday life, and we try to take the best options and opportunities. Decisions are made every moment. Possible worlds correspond to our daily opinions about alternatives and strategies about the fact that there are other ways of how things could be. It is obviously a risky hypothesis, though great achievements involve great risks. A plurality of worlds exists because the concept of possible world emerged to define possibility, and there are endless possibilities. When we talk about possibilities, we are imagining a possible world in which such alternatives occur. Through language we describe how other possible worlds are. Other possible worlds exist because we think about them, and this is a reason to believe in a plurality of worlds. Possible worlds have become a widely used philosophical term. We talk as if possible worlds would exist, and natural language that expresses modal statements is a sign that other worlds exist. Modal logic is intentional. We can talk about what could have been using the concept of possible worlds. Genuine modal realism has the great advantage that modal discourse is extensional. There are references to the terms in other worlds. If I say that I could have had brown eyes, I am talking about a counterpart of me that has brown eyes. The extension embraces all of my brown-eyed counterparts.
The strongest argument that can be advanced to support genuine modal realism is the achievement of modal reductionism. Modal terms can be defined in non-modal terms. If we talk about possibilities, we can secure our ability to express modalities if we begin with primitives that are not modal. A theory with the least possible primitives is better, and we can reduce everything to individuals and set-theoretic constructions of them. Due to modal reductionism, we can accept our modal opinions. If y would have happened, z would have happened. We have a "powerful tendency to think in modal terms" (Plantinga 1987, p. 202), and modal reductionism allows us to believe that things might have been different.
Summary of Chapters
1. Modalities: This chapter defines the four primary modalities—possibility, necessity, contingency, and impossibility—and explains how they interrelate within different logical, metaphysical, and physical frameworks.
2. Modal Logic: This chapter explores the historical development and formal foundations of modal logic, including Kripke's possible worlds semantics and the distinction between de dicto and de re statements.
3. Theories of Possible Worlds: This chapter provides an in-depth analysis of various ontological theories regarding possible worlds, comparing modal realism, actualist strategies, Neo-Meinongianism, and hybrid models.
4. Evaluation: This chapter assesses the competing theories, defending genuine modal realism for its explanatory power and economy while acknowledging the challenges of the theory.
5. Summary: This chapter encapsulates the core theses of the work, emphasizing the benefits of a hybrid account of modal realism that draws on both genuine and actualist perspectives.
6. Final Thoughts: This chapter reflects on the metaphysical nature of the inquiry, acknowledging the inherent difficulty in empirically verifying modal theories and the value of using such intellectual tools to understand reality.
Keywords
Possible worlds, modal realism, modality, necessity, possibility, contingency, ontology, Lewisian realism, counterpart theory, actualism, Neo-Meinongianism, impossible worlds, modal reductionism, de re, de dicto
Frequently Asked Questions
What is the primary focus of this thesis?
The thesis explores the philosophical concept of "possible worlds," examining how they are used to define modal notions like possibility and necessity, and evaluating different theories about what these worlds actually are.
What are the central themes discussed?
The core themes include the definition of modalities, the ontology of possible worlds (concrete versus abstract), the role of modal logic in linguistic analysis, and the debate between realists and antirealists regarding the existence of a plurality of worlds.
What is the main goal or research question?
The author aims to clarify the concept of possible worlds and evaluate whether genuine modal realism—specifically the theory proposed by David Lewis—is the most effective way to reduce modal concepts into non-modal terms.
Which scientific methodology is employed?
The thesis utilizes an analytical and interpretative method common in philosophy, assessing the logical consistency, explanatory power, and ontological commitments of various modal theories.
What is covered in the main body of the work?
The main body rigorously examines the definitions of modality, the development of modal logic, and contrasts different theoretical models like Plantingan realism, combinatorialism, and book modal realism, concluding with a critique and a personal synthesis.
Which keywords characterize this work?
Key terms include Possible worlds, Modal realism, Modality, Necessity, Possibility, Counterpart theory, and Actualism.
What is the difference between "genuine" and "actualist" modal realism?
Genuine modal realism, as advocated by David Lewis, posits that other possible worlds exist and are just as concrete and real as our own. In contrast, actualist modal realism holds that only the actual world is concrete, while possible worlds are merely abstract entities (such as states of affairs or sets of propositions).
How does the author resolve the "de dicto" vs. "de re" distinction?
The author relies on Lewis’ counterpart theory, which suggests that modal claims are not about identity across worlds but about the existence of "counterparts" that satisfy certain property descriptions in other worlds.
Why are "impossible worlds" considered in this thesis?
Impossible worlds are analyzed to address the "granularity problem" in propositional logic—helping to differentiate between inconsistent or impossible propositions that would otherwise be lumped together in traditional possible world semantics.
- Citation du texte
- Valery Berthoud (Auteur), 2016, Modal metaphysical puzzling possible words. An inquiry, Munich, GRIN Verlag, https://www.grin.com/document/375505
