The Metaphysics of Powerful Qualities

The author argues for the necessity of both dispositionality and qualitativity in properties by emphasizing their inseparability and their role in explaining the nature of properties. They argue that properties must combine both qualities to be fully understood. Key definitions include:

• Dispositionality: Defined as a property's ability to be nomically relatable, meaning it can be related to other properties through laws. This definition emphasizes the role of properties in determining the behavior of objects.
• Qualitativity: Defined as a property's need for nomic relations to determine its nomic role in different worlds. This definition highlights the dependence of properties on external relations for their identity and function.

The book discusses several versions of the Powerful Qualities View (PQV). The Identity Theory (IDT) posits that properties are identical to their dispositionality and qualitativity, but faces challenges in defining these concepts and the identity claim. The Grounding View suggests properties are qualitative due to intrinsic nature and dispositional due to grounding dispositions, but is unstable and may lead to other views. The Compound View, including Property Parts Theory and Property's Essence Parts Theory, suggests dispositionality and qualitativity are parts of properties, but struggles with identity and ontological commitments. Higher-Order Properties Theory (HOPT) posits dispositionality and qualitativity as higher-order properties, but faces issues with ontological structure and Armstrong's dilemma. The Dual Aspect Account views dispositionality and qualitativity as aspects of properties, but has metaphysical concerns. The book argues that these versions face various challenges and objections, and proposes a novel version, Powerful Categoricalism, which addresses these issues by emphasizing the intrinsic nature of properties and their nomic relatability.

The author proposes to address the "Governing Problem" by introducing a "Dualist Model" that posits both thin powers and ontologically robust nomic relations as the sources of natural modality. This model suggests that the specific behavior of things in the world is the outcome of both the thin powers properties possess and certain nomic relations that determine their nomological role. The Dualist Model supports the PQV by providing an alternative understanding of the main tenet that properties are both dispositional and categorical/qualitative. It does so by explaining how nomic relations "tell" properties what to do, thereby resolving the issue of how governing laws determine the behavior of objects.

The Powerful Qualities View (PQV) posits that properties are both dispositional and categorical/qualitative. Its advantages include addressing issues with monistic views like Pure Qualities Monism and Pure Powers Monism, offering a middle ground. Disadvantages include potential ontological complexity and challenges in defining dispositionality and qualitativity. The author argues for the superiority of Powerful Categoricalism (PC) over other PQV versions by demonstrating its compatibility with the Dualist Model, which explains the origin of natural modality. PC avoids the pitfalls of other views, like the identity regress problem and Armstrong's dilemma, and offers a more nuanced understanding of properties' ontological structure. Its ability to address these challenges and its alignment with the Dualist Model make PC a superior metaphysical view on properties.