Thirdly, We learn from anatomy, that the immediate object of power in voluntary motion, is not the member itself which is moved, but certain muscles, and nerves, and animal spirits, and, perhaps, something still more minute and more unknown, through which the motion is successively propagated, ere it reach the member itself whose motion is the immediate object of volition.
Hirugarrenik, Anatomiak irakasten digu ahalaren objektu zuzena, mugimen nahietsian, ez dela izatez mugiarazten den menbrua, halako muskulu-, nerbio-eta animali izpiritu batzuk baizik, eta agian zerbait niminoago eta ezezagunagoa, haien bidez hedatzen delarik segidan mugimendua, bere mugimena nahiaren objektu arartegabea den menbrua atzeman aurretik.