If we take the brain, expand it to the size of a building, walk into that building, what will we see? Mostly fat, protein and water, which translates into axons, dendrites and synapses. No where do we see an idea in the machinations of the brain. This calls into question just how information is processed in the brain.
There are three categories of information that I know of.
First, there is information like that of bioelectrical impulses going through the brain, much like a computer in relation with electricity and transistors.
Second, there is information that arises from material machination, which we call programming code. Much like how a computer can be programmed to move in a game of chess.
Third, there is information that is consciously known. It's like knowing that you know. It's Descarte saying, "I think therefore I am". It's information of awareness. It's called apperception. Which can be defined as:
How many computers for instance can perform a chess move, and
know that it is performing a chess move.
Let me illustrate this last kind of information more carefully by paraphrasing John Searle's Chinese room, Which can be found here,
http://en.wikipedia.org/wiki/Chinese_room
Imagine a man name John who knows nothing about Chinese culture or language and he enters into a room with Chinese figures all around him. There is a window, and on the other side of the window are Chinese observers. On the floor of this room that John is in is a set of cards. On one side of the cards are Chinese characters that he doesn't understand, but on the opposite side are a series of different dots. Furthermore, on the floor there are a series of dots which match up with the cards, so he has to match the same series of dots on the cards with the corresponding ones on the floor. Like a computer, he understands the rules and he lays the cards in the correct order on the floor, facing the Chinese characters up. Once down he stands back and he has finished his task flawlessly.
So what's missing here? What information is John not understanding? The cards are laid face up displaying the Chinese characters, and together they string a sentence that says a joke in Chinese, "What did the leper say to the prostitute? Keep the tip" Chinese observers laugh at this joke but John sits there scratching his head. John is unaware just like a computer is unaware of this third kind of information. Computers aren't aware, it's artificial simulation. They are dark inside, where we have this spark of conscious that illuminates the worlds with feelings, emotions, motives, purposes, goals, desires!
Further questions to consider when questioning a strictly materialist version of mind:
Will a computer ever understand a joke?
Will a computer ever see the beauty in a sunrise?
Will a computer ever feel an emotion, and not just simulate one?
I have so many questions about the mind, for instance, how can it be that modern physics is based on probablism yet our mind picks up on logical certainties. There is a modal mismatch here that is interesting. Shouldn't physics be probablism top to bottom if everything is reducible to physics? The brain just acts on action potentials not logical certainties.
Also, what is it about the soul that can make contact with universals such as the Pythagorean theorem? His theorem isn't right about an awful lot of rectilinear triangles but every single one. To further make my point, a person can go around measuring each and every triangle measuring it has a 180 degrees or they can just know by definition that A-squared plus B-squared = C-Squared. One doesn't learn that from empiricism, from observation! Just like one doesn't know that there is always a number higher than the next ad infinitum! So empiricism has it's challenges and the mind seems to be more than just a mere collection of experiences.
Take a war, expand the battle field so huge that you can begin to see all the physical particles. where in the flotsam and jetsam of particles do we see what the soldiers are fighting for? Where is justice, devotion, and courage on the physical level of explanation? Where are morals and beauty in the quantum physics of it all? Morals are a social phenomenon, not a physical one
There seems to be something that transcends the physical world here in some matter. Some call it epiphenomenalism, dualism, or some combine the two and say that there exists one substance with two properties, one side being mental, the other side being physical, and every particle has some fundamental essence of consciousness whatever that may be. David Chalmers calls this panpsychism, he works at Berkley University.
There are innumerable theories on this but these are my current thoughts on the matter.