Every passion, every emotion has its effect upon the mind, and every change of mind, however slight, has its effect upon man's body.:
Different conditions and the changes that take place in the world have their effect upon the mind, and the different conditions of the mind have their effect upon the body. As bodily illness makes man irritable, confused and exhausted in mind, so different conditions of the mind cause health or illness in the body. The link between the body and the mind is the breath, a link through which the influences of the body and the mind are exchanged and work upon one another.