the surrounding objects.  I paint them out to myself as existent at present, with the same qualities and relations, that I formerly knew them possessed of.  These ideas take faster hold of my mind, than the ideas of an inchanted castle.  They are different to the feeling; but there is no distinct or separate impression attending them.  It is the same case when I recollect the several incidents of a journey, or the events of any history.  Every particular fact is there the object of belief.  Its idea is modified differently from the loose reveries of a castle-builder:  But no distinct impression attends every distinct idea, or conception of matter of fact.  This is the subject of plain experience.  If ever this experience can be disputed on any occasion, it is when the mind has been agitated with doubts and difficulties; and afterwards, upon taking the object in a new point of view, or being presented with a new argument, fixes and reposes itself in one settled conclusion and belief.  In this case there is a feeling distinct and separate from the conception.  The passage from doubt and agitation to tranquility and repose, conveys a satisfaction and pleasure to the mind.  But take any other case.  Suppose I see the legs and thighs of a person in motion, while some interposed object conceals the rest of his body.  Here it is certain, the imagination spreads out the whole figure.  I give him a head and shoulders, and breast and neck.  These members I conceive and believe him to be possessed of.  Nothing can be more evident, than that this whole operation is performed by the thought or imagination alone.  The transition is immediate.  The ideas presently strike us.  Their customary connexion with the present impression, varies them and modifies them in a certain manner, but produces no act of the mind, distinct from this peculiarity of conception.  Let any one examine his own mind, and he will evidently find this to be the truth.

Secondly, Whatever may be the case, with regard to this distinct impression, it must be allowed, that the mind has a firmer hold, or more steady conception of what it takes to be matter of fact, than of fictions.  Why then look any farther, or multiply suppositions without necessity?

Thirdly, We can explain the causes of the firm conception, but not those of any separate impression.  And not only so, but the causes of the firm conception exhaust the whole subject, and nothing is left to produce any other effect.  An inference concerning a matter of fact is nothing but the idea of an object, that is frequently conjoined, or is associated with a present impression.  This is the whole of it.  Every part is requisite to explain, from analogy, the more steady conception; and nothing remains capable of producing any distinct impression.