Hare Krishna!

 Pain is experienced when a stimulus damages or threatens to damage 
body tissue. When agents harmful to the system stimulate the 
tissues, these nerve endings (nociceptors) produce some chemicals 
that generate an electric impulse, which is then transmitted 
through the nerve fibres. There exists an undoubted `Experience' 
which occurs when we are subjected to painful stimuli, resulting 
secondarily into a specific behavioral pattern like reflex withdrawal 
of hand on pin-prick etc. The description of passage of pain says 
nothing about the conscious perception of the pain. Also the 
conduction of impulses right up to the neuronal cells in the pain 
centers in the subcortical region does not reveal the actual 
experience of sadness and feeling of hurt due to pain. The description 
of brain even if elaborated in greatest possible details, would 
consist of nothing more than a list of statements about 
electrochemical states of brain cells. Such data might have some 
relevance on patterns of behavior, but they cannot explain 
consciousness because they do not even refer to it.

 The reality of our conscious perception is undeniable and our 
understanding of all other aspects of reality depends on this 
primeval fact. We all feel by direct perception that we have 
consciousness and it is the cause for our perception of all other 
stimuli including pain. There are innumerable examples showing 
how conscious awareness is entirely different from the physical 
behavior associated with it. For example what happens when a 
person accidentally strikes his thumb with a hammer ? Certain 
specific patterns of behavior result - the person may shout, 
wave his hand etc. The study of the body's reaction may reveal 
several kinds of electro-chemical changes like higher concentration 
of impulse generating chemicals and so on. While these measurable 
effects are part of the event, they are distinct from the experience 
of the pain itself. Although everyone readily understands the 
sensation of pain because it is a common conscious experience it 
cannot be defined in physical terms.

 If brain is no more than an information processing device of these 
impulses, then what makes it any different from the machines used to 
record the experimental data from the brain? The fact, however, is 
that a machine cannot feel pain while for an individual, pain is a 
reality he cannot deny. In case of human beings endowed with conscious 
awareness, physical description is inadequate to describe his personal 
experience.

 The Bhagavad-gita affirms the presence within the body of a distinct 
entity, the conscious self and establishes it as an irreducible 
individual quantum or atom of consciousness. The conscious self is 
superior to the brain and its functions. The situation of this 
conscious self can be compared to that of a pilot flying an airplane 
on instruments. Since the sensory apparatus of the body is composed 
of matter, this apparatus can provide information only about the 
configuration of material energy and their transformations.

 The techniques of material science are inadequate to 'prove' the 
existence of the soul in as much as the ear is incapable of detecting 
light. The soul can, however be realized as a higher reality by 
following the laws of spiritual science. Ultimately all spiritual 
truth is revealed and proved from within, by experience.