The statement that: “Consciousness exists within the brain.” is a physical analogy. It is similar the statement: “Sharks exist within the ocean.” There is a container/contained physical analogy that underlies that statement.
What do we learn about the mind from that comparison? What connection do we get, that is a knowledge candidate, or potential truth?
Well, we know that consciousness and brain are causally connected, by looking at certain specific cases. But, what cash-value do we get from conceiving of consciousness as an abstract physical thing like the brain? To go so far as to reduce consciouness to the brain is to believe in a fantasy – an intellectualist delusion.
There is a quality to the purely mental. My emotions are purely mental, and even though I may make a statement about emotions using physical analogies, that doesn’t mean that I meant that statement to be true like a specific factual statement is true – My statement is useful in a specific situation, a specific communicative context, which allows me to draw a relevant meaning in some setting, maybe the context is NOT a serious philosophical debate!!