When an object is lifted with the eyes closed, its weight is no different, whether or not the hand carries an extra weight (and whether this weight exerts pressure on the back of the hand or a pull on the palm) whether the hand is free or is fastened in such a way that the fingers work alone whether one or more fingers perform the task whether the object be raised with the hand or the head, foot or teeth and finally whether the object is lifted in the air or in Ibid.,.