Could you explain more about the Buddhist concept of human functioning? Does that contradict the idea of reincarnation? What exactly is being reincarnated if not a permanent immortal soul?
I understand there are different sects of Buddhism with varying beliefs and practices, just curious if this belief marks a separation from mainstream Buddhist practice.
morgan greywolf replied before me but I don't know where this will be placed in the thread, so I wanted to mention that.
One of the tenets of Buddhism is that things are "empty" meaning that they lack a separate self. Things are made up of non-self elements, to paraphrase Thich Nhat Hanh- for example, a tree is made up of soil, rain, sun, carbon dioxide, etc. The tree exists as a confluence of conditions; change one of those conditions and there would be no tree or at least a different tree. If you burn the tree, what happens? The things the tree is made up of are released and eventually become part of something else. This is rebirth (by the way, the Buddhist term is "rebirth" rather than "reincarnation"); I think if it as being closer to recycling than to the transmission of a soul from one body to another.
It is fundamental to human experience, most of the time anyway, to perceive ourselves as having an ongoing constancy- an "I" which is the foundation of the idea of the soul. This is probably an illusion, since who change throughout our lives- if we did not, we could neither grow nor learn.
Upstream, Kazoo mentioned brain injuries and memory problems. Memory is critical to a sense of a lasting self, of course. It may even be that memory *is* the sense of being a lasting self. But memories can be faked, can be lost, can be twisted beyond recognition. Memory is as much imagination as it is recollection. Disorders that affect cognitive functions can significantly alter the sense of self and, in the case of diseases like Alzheimer's, seem to destroy the sense of self in the long run. (Disclosure: I am a psychologist and one of my specialties is dementing illnesses). Diseases like depression and bipolar disorder distort the perception of being a self.