T 1.4.5.21

To apply this to the present case; there are two different systems of beings presented, to which I suppose myself under a necessity of assigning some substance, or ground of inhesion. I observe first the universe of objects or of body: The sun, moon and stars; the earth, seas, plants, animals, men, ships, houses, and other productions either of art or nature. Here Spinoza appears, and tells me, that these are only modifications; and that the subject, in which they inhere, is simple, incompounded, and indivisible. After this I consider the other system of beings, viz. the universe of thought, or my impressions and ideas. There I observe another sun, moon and stars; an earth, and seas, cover'd and inhabited by plants and animals; towns, houses, mountains, rivers; and in short every thing I can discover or conceive in the first system. Upon my enquiring concerning these, Theologians present themselves, and tell me, that these also are modifications, and modifications of one simple, uncompounded, and indivisible substance. Immediately upon which I am deafen'd with the noise of a hundred voices, that treat the |first hypothesis with detestation and scorn, and the second with applause and veneration. I turn my attention to these hypotheses to see what may be the reason of so great a partiality; and find that they have the same fault of being unintelligible, and that as far as we can understand them, they are so much alike, that 'tis impossible to discover any absurdity in one, which is not common to both of them. We have no idea of any quality in an object, which does not agree to, and may not represent a quality in an impression; and that because all our ideas are deriv'd from our impressions. We can never, therefore, find any repugnance betwixt an extended object as a modification, and a simple uncompounded essence, as its substance, unless that repugnance takes place equally betwixt the perception or impression of that extended object, and the same uncompounded essence. Every idea of a quality in an object passes thro' an impression; and therefore every perceivable relation, whether of connexion or repugnance, must be common both to objects and impressions.