 In view of the fact that we cease to be conscious of anything in dreamless sleep, it is evident that all sensations begin and cease to exist. There must be some continually existing cause capable of renewing them as we believe. The present question is how the continued entity which enters into the causes of all one’s sensations, without exception, is to be conceived. The ears, nose, and other organs of sense are objects of perception which we believe to exist when unperceived. But they are not the continued cause that is wanted because sensations that occur in dreams have exciting causes which do not continue when these sensations cease to exist. The continually existing cause of all renewed sensations whatsoever must be a subject of change that pre-exists and is altered by whatever sensations appear in consciousness. The mind thus comes to be conceived as a general capacity for sensation external to all its sensations, independent of them, and ready to be altered by any exciting cause that mixes with it –a thinly internal existent. Shepherd observes that “I” always refers to something abstract. 