libterm.com Strong supervenience describes a relationship between sets of properties where any change in one set necessitates a corresponding change in the other, ensuring a strict dependence without exceptions. This concept is crucial in metaphysics and philosophy of mind, as it helps explain how mental states depend consistently on physical states. Discover how strong supervenience shapes contemporary debates and what it means for Your understanding of property relations in the full article.
Table of Comparison
| Aspect | Strong Supervenience | Weak Supervenience |
|---|---|---|
| Definition | Property A strongly supervenes on Property B if, in every possible world, any two entities identical in B-properties are identical in A-properties. | Property A weakly supervenes on Property B if, within the same possible world, any two entities identical in B-properties are identical in A-properties. |
| Scope | Cross-world comparison of property instances. | Within-world comparison of property instances. |
| Modal Strength | Stronger modal commitment; supervenience holds across all possible worlds. | Weaker modal commitment; supervenience holds only in a single possible world. |
| Philosophical Implication | Supports necessity claims and metaphysical grounding. | Supports empirical regularities without metaphysical necessity. |
| Example | Physical properties strongly supervening on quantum states. | Ethical properties weakly supervening on cultural facts. |
Introduction to Supervenience
Supervenience describes a dependence relation where changes in one set of properties (the supervenient) are determined by changes in another set (the subvenient). Strong supervenience requires this dependence to hold across all possible worlds, asserting a global necessity between properties. Weak supervenience, by contrast, restricts this dependence to within a single possible world, allowing for variation across different worlds.
Defining Strong Supervenience
Strong supervenience is defined by the condition that any two entities cannot differ in their supervenient properties without differing in their subvenient properties across all possible worlds. It establishes a necessary dependence such that if entities share identical base properties, they must share identical supervenient properties universally. Unlike weak supervenience, which only requires this dependence within a single possible world, strong supervenience enforces a stricter, cross-world constraint on property relations.
Defining Weak Supervenience
Weak supervenience describes a relationship where if two entities are identical in all subvenient properties, they must also be identical in all supervenient properties within a single possible world. This contrasts with strong supervenience, which requires this correspondence to hold across all possible worlds, establishing a stricter dependency. Weak supervenience is often used in philosophy of mind and metaphysics to explain property dependence without demanding cross-world necessity.
Historical Context and Philosophical Roots
Strong supervenience emerged from the mid-20th century analytic philosophy, influenced by attempts to explain the dependency of mental states on physical states with necessity across all possible worlds. Weak supervenience, grounded earlier in the logic of properties and modal logic, captures dependency restricted to actual or specific possible worlds without requiring universal necessity. Both concepts trace back to discussions on the mind-body problem and the nature of property relations in philosophy of mind and metaphysics.
Key Differences Between Strong and Weak Supervenience
Strong supervenience requires that any two entities identical in all base properties must be identical in all supervenient properties across all possible worlds, ensuring a strict necessity relation. Weak supervenience, by contrast, only demands this dependence within the same possible world, allowing variability across different worlds while maintaining dependency locally. The key difference lies in the scope of dependency: strong supervenience enforces cross-world uniformity of supervenient properties given base properties, whereas weak supervenience restricts this uniformity to individual worlds without guaranteeing cross-world necessity.
Formal Definitions and Logical Structure
Strong supervenience is formally defined such that if two possible worlds are identical in all subvenient properties, then they must be identical in all supervenient properties, ensuring a necessity across possible worlds. Weak supervenience requires that within a single possible world, any two objects identical in subvenient properties must also be identical in supervenient properties, emphasizing a world-bound necessity. The logical structure of strong supervenience entails a cross-world constraint expressed as ww'xy((Sxwy Sxw'y) - (Pxwy = Pxw'y)), while weak supervenience is captured by wxy((Sxwy - (Pxwy = Pxyw))).
Illustrative Examples: Strong vs. Weak Supervenience
Strong supervenience occurs when any change in mental states necessitates a corresponding change in physical states across all possible worlds, exemplified by a pain sensation always correlating with a specific neural configuration regardless of context. Weak supervenience allows for variation across possible worlds, such as moral properties depending on physical properties within a single world but not necessarily across different worlds, highlighting dependence without strict cross-world necessity. These examples underscore the difference where strong supervenience demands global dependence while weak supervenience requires dependence only within particular worlds.
Applications in Philosophy of Mind
Strong supervenience asserts that mental properties are entirely determined by physical properties across all possible worlds, implying a necessary connection crucial for non-reductive physicalism in the philosophy of mind. Weak supervenience, by contrast, holds that mental properties depend on physical properties only within a single possible world, accommodating multiple realizability and supporting functionalist perspectives on mental states. These distinctions aid in debates about mind-body relations, especially concerning whether mental states can be fully explained by or reduced to physical states.
Criticisms and Debates in Contemporary Philosophy
Strong supervenience faces criticism for its requirement that property relations hold across all possible worlds, which some argue imposes an overly rigid metaphysical structure that neglects context-sensitivity and the variability of properties in different conditions. Weak supervenience is debated for its relative permissiveness, as it only demands property dependence within a single world, leading critics to question its ability to adequately explain necessary connections or the nature of property determination across possible worlds. Contemporary philosophical debates focus on whether strong or weak supervenience better captures the metaphysical relations between properties without resorting to problematic essentialism or failing to ground modal dependencies effectively.
Conclusion: Implications and Future Directions
Strong supervenience ensures that identical base properties necessarily determine identical higher-level properties, implying a rigid dependence crucial for metaphysical grounding and scientific reduction. Weak supervenience allows variation across possible worlds, highlighting limitations in explaining cross-world property relations and emphasizing the need for refined frameworks in philosophy of mind and metaphysics. Future research should explore hybrid models integrating modal and non-modal aspects to better capture complex dependencies in property relations and enhance theoretical clarity.
Strong supervenience Infographic
