According to materialists, all mental states are simply different brain states. This means that different neurons fire at different times, and therefore form different states- bringing on different feelings and emotions.
A situation often supporting this theory would be that of pain. When we feel a pain, we immediately think that the pain is in the actual body part where the pain was inflicted. The thing that proves this wrong would be that of in the case of amputation. Someone may have amputated his foot, but he would still complain about a pain in his foot. This obviously means that the pain cannot be in the foot; it must be in the brain. And this must be so for everyone.
Even if we accept that pain is simply a brain state, we cannot yet prove which brain state it is. We can only believe that one day, scientists will prove this, just as water was proven to be H 0.
This theory sounds very scientific, and many scientists believe this to be true.
The opposite theory would be that we all have a soul. The body and the person himself, the soul, are two different things. The soul is the thing that has conscious experiences, and the thing that thinks and feels. According to those who believe in this theory, there is a physical process, going through to the brain, but that happens is not the brain’s experience- it is the soul’s. One of the arguments for this would be that of the brain’s state does not change when the feelings do. The example given is that although a smell may feel sharp and tangy, the brain itself will remain the same as it always is. The mind is something private that only the person himself has access to. No one else can experience those feelings, and if someone would open up your brain, they still would not know what feelings were in there. The idea of a soul is also a religious belief. Many believe that after the physical body dies; the soul carries on and goes up to heaven. Others believe in reincarnation- that when they die, their souls pass on to a new physical body.
The big problem with this theory is that if there were such things as souls, it seems they would not be able to affect what our bodies do.
However, an argument for the soul theory would be that of eyeless aliens. They are highly intelligent but cannot see. They are conscious but they do not have any experience of color. They are very curious of humans and how it would be to experience the world as a human. They make you look at different red objects, and as you experience the color red, they scan your body, finding out exactly what is going on in the body, down to each atom. Even though the aliens now have all the physical information, they will still not know what it is actually like to have an experience of red. Therefore it seems that no matter how much information one gathers about what is going on inside a human physically when one has an experience, including what is going on inside the brain, one still will not know what the experience is actually like from the point of view of the person having it.
So it seems that the mind has to be part of the physical world. Yet, on the other hand, it seems it cannot be part of it. This question is still being debated, and it still seems there is no right or wrong answer.
Freud would support the soul theory. His idea of the unconscious definitely states that it is not of the physical world. Most things in the physical world can be proven and shown that they exist. The unconsciousness cannot be proven as such, and therefore Freud would not believe that the mind is a physical thing.
He would probably argue that anything that is of the physical world could be studied, and broken down into smaller particles of matter, and analyzed and examined as such. Things of the physical world can be looked into and what is going on can be determined. Freud’s concept of the mind, however, cannot be broken down into atoms and analyzed, and it cannot be looked into, and one cannot determine what is going on by opening it up. Freud’s idea was that everyone’s mind is unique, and private, and something that no one else has access to. This means that all experiences are personalized, and that no one can experience, or see, those thoughts and feelings that a person has. The idea of the unconscious being something we cannot analyze or explain, therefore eliminates the possibility of it being of the physical world.