Definition
What acts on what is the problem of causal relations between emergent mental descriptions and underlying physical descriptions. Carroll argues higher-level causes can be real within their vocabulary.
Why It Matters
If we believe that only “atoms” are real, we lose the ability to talk about purpose, choice, or meaning. Carroll’s “what acts on what” model saves our agency by proving that mental causes can be real without violating physics, allowing us to be both scientific and human.
Core Concepts
- Mental causes do not compete with physical causes if they describe the same process at another level.
- Emergent causal language tracks patterns useful for intervention and explanation.
- Bottom-up physics and top-down reasons can both be valid descriptions.
- Causal talk is domain-relative.