Something related to this was discussed on the "definition of belief" 
thread. I don't remember exactly who expressed what views, but I 
remember quite a problem with the true existance of belief. Someone said 
something to the effect that "If one believes in x, then one acts as 
though x is true". This was questioned with "What if belief in x 
necesitates no observable action?" This can be rephrased for our current 
discussion; what if the existance of x leaves no observable evidence of 
it's existance? 
-- John Aten jwa@inx.net