“Mary’s Room” is a hypothetical argument about a neuroscientist named Mary who has only ever experienced living in a black-and-white room. However, she has all the physical information needed to understand the visual system, and what it means to see things like the sky and colors like blue. One day, Mary is able to leave the room, and sees the color red. Does Mary learn anything?
The argument against a physical explanation for consciousness is as follows:
- Mary knows all the physical facts about the brain.
- Mary learns a new fact about consciousness when she leaves the black-and-white room: what it is like to see red.
- Hence, facts about consciousness are not included in the physical facts about the brain.
Jackson (1982) uses this to conclude that physical information is not all the information in the world. Rather, the physicalist scheme leaves out qualia.
Objections to Jackson’s argument include:
- Mary is not learning anything new.
- Mary is not learning a new fact, but gaining a new ability.
- Mary is not learning a new fact about consciousness, but learning another way to describe a physical fact.