Physicalism SEP

1. Introduction to Physicalism

• Physicalism: the thesis that everything is physical; a metaphysical stance similar to historical views like Thales' idea that everything is water or Berkeley's idealism that everything is mental.

• The universe and its constituents are argued to conform to the condition of being physical, as the physicalists maintain that what seems non-physical (biological, psychological, moral, etc.) ultimately relates to the physical.

2. Preliminaries

• 2.1 Terminology: Sometimes synonymous with 'materialism', but historically differs; materialism refers to matter, while physicalism emphasizes both matter and other physical entities (e.g., forces).

• 2.2 Historical Issues: Physicalism's origins trace back to pre-Socratic thinkers like Democritus and extend through modern thinkers such as Marx, Hobbes, and empiricists like Hume and Mill.

• 2.3 A Framework for Discussion: Distinguishes between the interpretation question (meaning of 'everything is physical') and the truth question (is it true?).

3. The Completeness Question

• Explores what relation everything bears to the physical if physicalism is true.

• Strategies to address:

  • Modal notions (involving possibility and necessity)

  • Non-modal notions (like identity in the logical sense).

• Supervenience: A key concept where mental/biological/social properties supervene on physical properties.

3.1 Supervenience and Necessity Physicalism

• Supervenience implies no two worlds can differ in mental/social properties without differing physically.

• Example: Dot-matrix picture reflecting global properties (like social properties) that supervene on dot arrangements (akin to physical properties).

• A formulation introduces Supervenience Physicalism with:

  • (1) Physicalism is true if every world that is a physical duplicate is a duplicate of everything.

3.2 Identity Physicalism

• Proposes two formulations: Token Physicalism (each thing is a physical particular) and Type Physicalism (every property is identical to a physical property).

• Identifier for Type Physicalism:

  • (4) If every property at a world is identical to a physical one, physicalism may be true.

3.3 Realization Physicalism

• Suggests properties must either be physical or realized in a physical property to maintain physicalism.

• Two forms: Second-order Realization Physicalism and Subset Realization Physicalism.

3.4 Grounding Physicalism

• Centers on properties being grounded in or realized by physical properties, distinguishing itself from supervenience.

3.5 Fundamentality Physicalism

• Focuses on fundamental properties, arguing that if they exist, all must be physical.

3.6 Varieties of Physicalism

• Divides into Reductive (properties relate uniformly) and Non-Reductive (properties can derive without identity).

• Explores A Priori (knowledge without experience) and A Posteriori (knowledge relying on experience) physicalism.

4. The Condition Question

4.1 Definition of Physical

• Involves theory-based (physical properties validated by science) and object-based (properties typical of physical objects) conceptions.

• Points to potential circularity in defining physicality without referencing existing physical frameworks.

4.2 Challenges and Dilemmas

• Hempel's dilemma: Concerns whether physicalism defined through contemporary physics is insufficient due to possible incompleteness.

• Panpsychism Problem: The question of whether attributing consciousness to physical objects conflicts with physicalism.

4.3 Approaches (Via Negativa, Structuralism)

• The Via Negativa suggests defining physical properties by exclusion of non-mental properties, although faced with challenges regarding duality and overlap.

• Structuralist Approaches: Emphasize locked definitions through mathematical/logical terminology as a foundation for physicalism.

• Concludes with an attitude-based definition of physicalism, acknowledging potential discrepancies with established historical understandings.

5. The Case Against Physicalism

5.1 Qualia and Consciousness

• Jackson’s Knowledge Argument: Highlights the limitations of physicalism via a thought experiment with Mary, illustrating gaps in understanding consciousness.

• Responses range from ability hypotheses to positing a posteriori variants of physicalism.

5.2 Meaning and Intentionality

• Examines intentionality in understanding meaning via dispositional theories, with critiques and counterarguments against Kripke's challenges.

5.3 Abstracta

• Abstract objects like numbers pose challenges against physicalism, with possibilities for solutions including nominalism or topic-neutral property expansion.

5.4 Methodological Issues

• Critiques physicalism as misaligning with the naturalistic project of science, leading to potential contradictions in assumptions about metaphysical commitments.

6. The Case for Physicalism

6.1 The Argument from Causal Closure

• Asserts all events have physical causes leading to the conclusion that mental states must supervene on physical states.

6.2 The Argument from Methodological Naturalism

• Claims rational inquiry into metaphysical commitments through natural scientific methods leads toward a physicalist understanding of the world, contrasting reasons against negating this perspective.