" ... all these interactions are linked by an unseen, all-embracing power ..."

"For instance, as we have observed, co-operation among the constituent parts of the human body is clearly established, and these parts and members render services unto all the component parts of the body. For instance, the hand, the foot, the eye, the ear, the mind, the imagination all help the various parts and members of the human body, but all these interactions are linked by an unseen, all-embracing power, that causeth these interactions to be produced with perfect regularity. This is the inner faculty of man, that is his spirit and his mind, both of which are invisible."

‘Abdu’l-Bahá, Tablet to Dr. Auguste Forel