Disease is the misery of our belief, happiness is the health of our wisdom, so that man's happiness or misery depends on himself. Now, as our misery comes from our belief, and not from the thing believed, it is necessary to be on the watch, so as not to be deceived by false guides. Sensation contains no intelligence or belief, but is a mere disturbance of the matter, called agitation, which produces mind, and is ready to receive the seed of error. Ever since man was created, there has been an element called error which has been busy inventing answers for every sensation.