thing still more minute and more unknown, thro' which the Motion is successively propagated, 'ere it reach the Member itself, whose Motion is the immediate Object of Volition. Can there be a more certain Proof, that the Power, by which this whole Operation is perform'd, so far from being directly and fully known by an inward Sentiment or Consciousness, is, to the last degree, mysterious and unintelligible? Here the Mind wills a certain Event: Immediately, another Event, unknown to ourselves, and totally different from that intended, is produc'd: This Event produces another, equally unknown: Till at last, thro' a long Succession, the desir'd Event is produc'd. But if the original Power were felt, it must be known: Were it known, its Effect must also be known; since all Power is relative to its Effect. And vice versa, if the Effect be not known, the Power cannot be known or felt. How indeed can we be conscious of a Power to move our Limbs, when we have no such Power; but only that to move certain animal Spirits, which, tho' they produce at last the Motion of our Limbs, yet operate in a Manner, that is altogether beyond our Comprehension?
We may, therefore, conclude from the whole, I hope, without any Temerity, tho' with Assurance; that our Idea of Power is not copy'd from any Senti-ment
