It is certainly true that at the back of every apparent cause there is lack of harmony; some part of man's being is out of tune, and the jarring note sets up vibrations which affect the whole system. It may be that there is some habit or weakness in his life which is poisoning the springs of his being. No one who is holding in his consciousness anything which falls below his own ideal can be in a state of harmony, for all the time - whether he is aware of it or not - the struggle for mastery between the higher and the lower self is going on.