Narrow Content and Intrinsic Mental Properties

Core Idea

Narrow content is meaning a mental state has from intrinsic physical/neural properties alone, independent of external environment. Wide content depends on external factors. This distinction matters for computational theories (assuming narrow internal content) yet content also depends on causal connections to the world.

Explainer

From content externalism, you know the Twin Earth thought experiment: Oscar and Twin-Oscar have molecule-for-molecule identical brains, yet their mental states have different contents — "water" picks out H₂O for Oscar and XYZ for his twin. Content, on the externalist view, is wide: it depends on factors outside the skin. This creates a puzzle. If cognition is computation defined over internal states, and if content is what those states are *about*, then wide content seems wrong for computational purposes — two physically identical systems would have different contents depending on their environment.

Narrow content is the proposed solution: a type of mental content fixed entirely by intrinsic physical or functional states, independent of environment. Whatever Oscar and Twin-Oscar share — their identical computational structure — constitutes their narrow content. Wide content then adds environmental context on top. Think of narrow content as a function: given the same internal state in different environments, you get different wide contents. Narrow content is like a recipe; wide content is the finished dish when you supply the actual ingredients (the environment).

The motivation is strongest in computational theories of mind. If the mind is a computing machine, then its operations must be determined by internal states alone — a Turing machine does not need to know whether its symbols refer to real-world objects to run its program. Jerry Fodor argued that a scientific psychology needed narrow, causally efficacious content to explain behavior. Behavior seems to track internal states more tightly than external referents: if you believe there's a tiger in front of you (even when there isn't), you run — the behavior is caused by the internal state, not by the actual tiger.

The difficulties are significant. Critics argue that narrow content is either too thin to be genuine *content* (a mere formal structure without referential significance) or cannot be non-trivially specified without appealing to wide content. If narrow content is just syntax — a formal role unconnected to the world — it is unclear what work it does in explaining intentionality. The de re attitudes you have studied illustrate this tension: to believe that *that man* is a thief, the very individuation of "that man" seems to require an environmental relation, not just an internal state.

The narrow-wide distinction marks a fault line between internalists (the mind's contents are fixed by what is inside the skull) and externalists (the mind's contents reach out into the world). How you resolve this question has downstream consequences for computational theories of mind, for debates about mental causation, and for what a complete science of the mind would look like.