It has been said that the brain can account for all forms of behavior, and for the majority of the time this is true. Emotions and behaviors associated with them can be the result of stimuli or hormones, but are all the direct result of the nervous system. Some belive that humans are unique in that they have a "mind" or a "soul", but both of these can be dramatically altered and effected by a variety of so called mind-altering drugs. These drugs do nothing more than effect the brain, and thus show that both the mind and soul are dependant on the brain. But there are two things that are very difficult to prove.

The first deals with identical twins. These twins would have the same DNA and thus the same brain. In many twins, there are identical habits and personalities. There have been multitudes of stories of the twins separated at birth and reunited as adults. They have the same hobbies, similar looking homes, spouses, jobs, etc. But then what accounts for the identical twins that are not alike in behavior? Perhaps you could attribute this to cytoplasm differences in the original split of their two begining cells, but then why would this happen with some twins and not with others?

The second thing that is hard to identify with the brain is the sense of death that some people have for a loved one. While this is not a common phenomna, it is documented in common science. Again, this is common between twins, but also happens between spouses and other family members. If a person is not near their dead loved one, and everything is controlled by the brain, how can people know of the death. Is the notion that the psychic world exists perhaps true? And if so how?

Nice argument from drug effects. Will talk more about identical twins, but remember that brains change depending on their own activity, so there is an available possible explanation for differences in brains (and behavior) in identical twins. Both an obvious one and a more subtle one. Psychic world an intriguing question, has interested brain researchers since William James. Will try and get to it, at least indirectly, later in course. PG