_Possibility of recalling._--But here the question arises how it is possible, by a voluntary effort, to recall what is once gone from the mind. Does not the very fact of a volition imply that we have already in mind the thing willed and wished for? How else could we will to recall it? This is a philosophical puzzle with which any one, who chooses, may amuse himself. I have forgotten, for instance, the name of a person: I seek to recall it; to recall what? you may ask. That name. _What_ name? Now I do not know what name; if I did, I should have no occasion to recall it. And yet, in another sense, I do know what it is that I have forgotten. I know that it is a name, and I know whose name it is; the name, viz., of this particular person. And this is all I need to know in order to have a distinct, definite object of volition before my mind. _The Mode of Operation._--The process through which the mind passes in such a case, is, to dwell upon some circumstances not forgotten, that are intimately connected with the missing idea, and through these, as so many connecting links, to pass over, if possible, to the thing sought. I cannot, for example, recall the name, but I remember the names of other persons of the same family, class, or profession, or I remember that it begins with the letter B, and then think over all the names I know that begin with that letter; and, in this way, seek to recall, by association, the name that has escaped. _Memory not an immediate Knowledge._--It has been held by some that memory gives us an _immediate_ knowledge of the past. This is the view of Dr. Reid. If, by immediate knowledge, we mean knowledge of a thing as existing, and as it is in itself--nothing intervening between it as a present reality, and our direct cognizance of it--then not in this sense is memory an immediate knowledge; for a past event is no longer existent, and cannot be known as such, or as it is in itself; it no longer _is_, but only _was_. Hence an immediate knowledge of it, is, as Sir William Hamilton affirms, a contradiction. Still, we may know the past _as it was_, not less really and positively than we know the present as it is. I as really know that I sat at this table yesterday as I know that I sit here now. I am conscious of being here now. I was conscious of being here then. That consciousness is not to be impeached in either case. If the senses deceived me yesterday, they may deceive me to-day. If consciousness testified falsely then, it may now. But if I was indeed here yesterday, and if I knew then that I was here, and that knowledge was certain and positive, then I know _now_ that I was here yesterday, for memory recognizes what would otherwise be the mere conception of to-day, as identical with the positive knowledge of yesterday. Memory may possibly be mistaken as to the so-called positive knowledge of yesterday; and so sense may be mistaken as to the so-called positive knowledge of the present moment.