species of sensation we call heat.’ If I afterwards remembered the succession of the feeling upon the sight, both objects (according to Hume’s original usage of terms [3]) would be ideas as distinct from the impressions; or, if upon seeing the flame I remembered the previous experience of heat, one object would be an idea; but we should not reckon it a case of reasoning. ‘In all cases wherein we reason concerning objects, there is only one either perceived or _remembered_, and the other is supplied in conformity to our past experience’--supplied by the only other faculty than memory that can ‘supply an idea,’ viz. imagination. [4] [1] Pp. 376, 384. [Book I, part III., secs. II. and IV.] [2] Pp. 327, 375. [Book I, part I., sec. VII. and part III., sec. III.] [3] Above, par. 195. [4] Pp. 384, 388. [Book I, part III., secs. IV. and V.] Relation of cause and effect the same as this transition. 285. This being the only account of ‘inference from the known to the unknown,’ which Hume could consistently admit, his view of the relation of cause and effect must be adjusted to it. It could not be other than a relation either between impression and impression, or between impression and idea, or between idea and idea; and all these relations are equally between feelings that we experience. Thus, instead of being the ‘objective basis’ on which inference from the known to the unknown rests, it is itself the inference; or, more properly, it and the inference alike disappear into a particular sort of transition from feeling to feeling. The problem, then, is to account for its seeming to be other than this. ‘There is nothing in any objects to persuade us that they are always _remote_ or always _contiguous_; and when from experience and observation we discover that the relation in this particular is invariable, we always conclude that there is some secret _cause_ which separates or unites them’. [1] It would seem, then, that the relation of cause and effect is something which we infer from experience, from the connection of impressions and ideas, but which is not itself impression or idea. And it would _seem_ further, that, as we infer such an unexperienced relation, so likewise we make inferences from it. In regard to identity ‘we readily suppose an object may continue individually the same, though several times absent from and present to the senses; and ascribe to it an identity, notwithstanding the interruption of the perception, whenever we conclude that if we had kept our hand or eye constantly upon it, it would have conveyed an invariable and uninterrupted perception. But this conclusion beyond the impressions of our senses can be founded only on the connection of _cause and effect_; nor can we otherwise have any security that the object is not changed upon us, however much the new object may resemble that which was formerly present to the senses.’ [1] P. 376. [Book I, part III., sec. II.]