Causal closure¶

A metaphysical thesis that every physical event with a cause sufficient for its occurrence has a sufficient physical cause within the physical domain.

Version: v2 · 2026-09-19 · History
Domain-specific #: 3627
Domain group: Humanities
Origin domain: Philosophy
Subdomain: Philosophy of Mind → Philosophy

Core Idea¶

Physical causal closure states that physical effects are causally complete within the physical domain, a premise used in arguments about mental causation, physicalism, and causal overdetermination. The thesis closes explanatory causal chains for physical events under physical causes, creating pressure on any allegedly additional nonphysical causal contribution to avoid exclusion or systematic overdetermination. The abstraction is therefore identified by a declared carrier, a transformation or constraint over that carrier, and an invariant that tells an analyst whether the named structure is genuinely present.

How would you explain it like I'm…

The Physical Story Is Complete

When a ball rolls or a leaf falls, something physical made it happen, like a push or gravity. Causal closure is the idea that every physical happening that has a cause has a physical cause that is enough all by itself. Philosophers use it to ask how thoughts and feelings could make anything happen.

The Complete Physical Chain

Causal closure is a claim in philosophy that every physical event that has a cause has a physical cause that is enough, all on its own, to bring it about. It says you never have to go outside the physical world to fully explain what happens in it. Philosophers use this idea in arguments about the mind. If it's true, then any non-physical mind that also causes things would seem either unnecessary or to be causing things that were already fully caused.

Physical Causal Completeness

Physical causal closure is the thesis that every caused physical effect has a sufficient physical cause. It is a key premise in arguments about mental causation, physicalism, and causal overdetermination. If the physical chain behind an event is already complete, then any extra non-physical cause, like a non-physical mind, seems either to do no work, which is the exclusion problem, or to make every such event doubly caused, which is systematic overdetermination. Closure does not by itself say that only physical things exist; it is a claim about causal sufficiency within the physical domain. How strong it is depends on how 'cause' and the modal claim are interpreted.

Physical causal closure states that physical effects are causally complete within the physical domain: for every caused physical effect in scope, a causally sufficient physical cause is available. The thesis must be stated relative to a declared notion of causation and modal strength — for example, whether sufficiency is nomological and whether closure concerns causes or causal explanations. It functions as a premise in arguments about mental causation, physicalism, and overdetermination: combined with the claim that mental states cause physical effects and the denial of systematic overdetermination, it pressures one toward identifying mental causes with physical ones. Any purportedly nonphysical cause of a physical event must either be excluded as causally idle or accept that the event is overdetermined. Closure is distinct from physicalism itself; it constrains causal structure without by itself saying what exists.

Scope of Application¶

Causal closure belongs to philosophy of mind and is useful where the analyst can specify the typed philosophy of mind carrier, defining objects and relations, parameters, conventions, evidence, boundary cases, and comparison targets, then evaluate for every caused physical effect in scope, a causally sufficient physical cause is available under the declared causal and modal interpretation. The scope is broad within that domain but bounded by the need for for every caused physical effect in scope, a causally sufficient physical cause is available under the declared causal and modal interpretation. The entry records a descriptive analytical identity; practical use requires the governing domain's evidence, standards, and safety obligations.

Clarity¶

The abstraction clarifies a crowded vocabulary by making for every caused physical effect in scope, a causally sufficient physical cause is available under the declared causal and modal interpretation the center of the account. A claim should name the carrier, the governing operation or relation, the applicable assumptions, and the recognition test. A bare label is insufficient because the name Causal closure can be used for a formal identity, an implementation, or a neighboring result unless carrier and convention are stated.

Manages Complexity¶

Without the abstraction, an analyst must reason directly over many local details: the carrier roles, admissibility assumptions, competing conventions, derived invariants, boundary cases, and proof or validation obligations specific to Causal closure. Causal closure compresses them into the roles in the structural signature. That compression permits comparison across instances without erasing the variables that determine validity. It also exposes which details may be varied safely and which are constitutive.

Abstract Reasoning¶

Identify the carrier. State what the elements, states, objects, or observations are: the typed philosophy of mind carrier, defining objects and relations, parameters, conventions, evidence, boundary cases, and comparison targets. Reject examples whose alleged carrier belongs to a different problem.
Lock the constitutive rule. Express for every caused physical effect in scope, a causally sufficient physical cause is available under the declared causal and modal interpretation independently of one notation or implementation.

Knowledge Transfer¶

Knowledge transfers strongly among subfields of philosophy of mind because they reuse the typed philosophy of mind carrier, defining objects and relations, parameters, conventions, evidence, boundary cases, and comparison targets, The thesis closes explanatory causal chains for physical events under physical causes, creating pressure on any allegedly additional nonphysical causal contribution to avoid exclusion or systematic overdetermination., and type the carrier, state every parameter and convention in the definition, test that for every caused physical effect in scope, a causally sufficient physical cause is available under the declared causal and modal interpretation, compare the nearest accepted identity, and report counterexamples, uncertainty, and limiting cases.

Relationships to Other Abstractions¶

Current abstraction Causal closure Domain-specific

Parents (1) — outgoing typed relations

Causal closure is a kind of Causality Prime

What makes it its own entry: the domain-specific identity determined by for every caused physical effect in scope, a causally sufficient physical cause is available under the declared causal and modal interpretation.

Hierarchy path (1) — routes to 1 parentless root

Causal closure → is a kind of Causality → is a kind of Dependency

Neighborhood in Abstraction Space¶

Causal closure sits in a crowded region of the domain-specific corpus (13^th percentile for distinctiveness): several abstractions share nearly its structure, so a description that fits it tends to fit its neighbors too.

Family — Metaphysics of Mind & Knowledge (23 abstractions)

Nearest neighbors

Computed from structural-signature embeddings · 2026-10-25