Powers and Principles, on which the Influence of these Objects entirely depends. Our Senses inform us of the Colour, Weight, and Consistence of Bread; but neither Senses nor Reason ever can inform us of those Qualities, which fit it for the Nourishment and Support of a human Body. Sight or Feeling convey an Idea of the actual Motion of Bodies; but as to that wonderful Force or Power, which would carry on a moving Body for ever in a continu'd Change of Place, and which Bodies never lose but by communicating it to others; of this we cannot from the most distant Conception. But notwithstanding this Ignorance of natural Powers and Principles, we always presume, where we see like sensible Qualities, that they have like secret Powers, and lay our Account, that Effects, similar to those, which we have experienc'd, will follow from them. If a Body of like Colour and Consistence with that Bread, which we have formerly eat, be presented to us, we make no Scruple of repeating the Experiment, and expect, with Certainty, like Nourishment and Support. Now this is a Process of the Mind or Thought, of which I would willingly know the Foundation. 'Tis allow'd on all hands, that there is no known Connexion betwixt the sensible Qualities and the secret Powers; and consequently, that the Mind is not led to form such a Conclusion concerning their constant and regular Conjunction, by any thing it knows of their Nature. As to past Ex-perience,
