Augustine, Confessions §aug_conf_08_020: Lastly, in the very fever of my irresoluteness, I made with my body many such...

Lastly, in the very fever of my irresoluteness, I made with my body many such motions as men sometimes would, but cannot, if either they have not the limbs, or these be bound with bands, weakened with infirmity, or any other way hindered. Thus, if I tore my hair, beat my forehead, if locking my fingers I clasped my knee; I willed, I did it. But I might have willed, and not done it; if the power of motion in my limbs had not obeyed. So many things then I did, when "to will" was not in itself "to be able"; and I did not what both I longed incomparably more to do, and which soon after, when I should will, I should be able to do; because soon after, when I should will, I should will thoroughly. For in these things the ability was one with the will, and to will was to do; and yet was it not done: and more easily did my body obey the weakest willing of my soul, in moving its limbs at its nod, than the soul obeyed itself to accomplish in the will alone this its momentous will.