The Literal Meaning of Genesis
ceeds from a part of the body that is stationary. For example, one finger alone is not moved unless the hand is stationary and the finger moves from its joint, which serves as a motionless pivot.28 When the whole hand, then, is moved from the elbow joint, the elbow from the humerus, and the humerus from the scapula, while the pivots from which the motion proceeds remain unmoved, the member that is moved goes through space. Thus, the joint of the foot is in the ankle, and the foot moves while the ankle joint is motionless. So, too, the joint of the shank is in the knee, and that of the whole leg is in the hip.
Now, the will causes no motion in any member whatsoever except from the pivot of some joint; and the command of the will originally directs the motion so that what is set in motion may be able to be impelled by that which does not move in space. Finally, in walking, one foot is not raised unless the other, firmly fixed, bears the weight of the whole body, while the foot in motion from the place at which it started to that where it is going is dependent upon the stationary joint which serves as a pivot.
42. The will, then, moves no member of the body through space except from a joint which remains unmoved. Furthermore, that part of the body which is moved and that part which is fixed so that the other can be moved has each its own corporeal dimensions by which it occupies space. With much greater reason, then, can we say that the soul which commands the movement remains unmoved in space. The members are subject to it, so that according to its desire the joint on which the member to be moved depends is firmly fixed. The soul is not a corporeal substance and does not fill the body in space as water does a skin bottle®? or a sponge, but in a mysterious way by its incorporeal command it is united to the body which it vivifies, and by this command it rules the body through an influence,!°° not a corporeal mass. With all the more reason, then, the will commanding does not itself move through space in order to move the body through space when it moves the whole by means of the parts, without moving any parts in space except by means of those which it keeps immobile.