Evidence · Case 08 · Science
The physicalist explanation, consciousness is just brain activity
One exhibit from the free evidence repository at apologetics.pro.
On this view, consciousness simply is what the brain does, and the sense that something extra needs explaining is an illusion that will fade as neuroscience matures. Daniel Dennett, who died in 2024, was its best known defender, arguing that the hard problem is a conceptual mistake rather than a real gap. Stated fairly, this is the mainstream naturalist position.
This is the leading opposing view. The response is that a complete map of which neurons fire still does not tell you what red looks like to the person seeing it.
Sources
Daniel Dennett, “Consciousness Explained” (Little, Brown and Company, 1991)
Objections & responses
- “A complete map of which neurons fire still doesn’t tell you what red looks like” is just the knowledge argument, which Dennett has answered at length. Stating the opposing view fairly requires stating its answer.
Fair. Dennett’s reply to the knowledge argument is that what red looks like is a set of functional dispositions, and that Mary in Frank Jackson’s thought experiment would not learn a new fact on leaving her black-and-white room but acquire new abilities. Jackson himself later abandoned the knowledge argument, which is worth knowing. The debate is not settled in either direction, and both moves should be on the table before you decide whether the hard problem is real.