16. The action of spirits upon spiritual fluids has consequences of a direct and capital importance for incarnated beings. From the instant that these fluids are the vehicle of thought, that thought can modify the properties of them. It is evident that they must be impregnated by the good or bad qualities of the thoughts which put them in vibration, modified by the purity or impurity of the sentiments. Bad thoughts corrupt the spiritual fluids, as deleterious miasmas corrupt the air we breathe. The fluids which surround or that project bad spirits are then vitiated, whilst those which receive the influence of good spirits are as pure as the degree of moral perfection to which they have attained.