It is in the first place plain that no intelligence could exist so as to adjust “means” to “ends,” except by the aid of memory; and “memory” has therefore been freely attributed even to the lower animals. Let us see, then, what the term “memory” really denotes. Now we cannot be said to _remember_ anything unless we are conscious that what is again made present to our mind has been present to our mind before. An image might recur to our imagination a hundred times, but if at each recurrence it was for us something altogether new and unconnected with the past, we could not be said to remember it. It would rather be an example of extreme “forgetfulness” than of “memory.” In “memory,” then, there are and must be two distinct elements. The first is the reproduction before the mind of what has been before the mind previously, and the second element is the recognition of what is so reproduced as being connected with the past. There is yet a further distinction which may be drawn between acts of true recollection. We are all aware that every now and then we direct our attention to try and recall something which we know we have for the moment forgotten, and which we instantly recognise when we have recalled it. But besides this voluntary memory we are sometimes startled by the flashing into consciousness of something we had forgotten, and which we were so far from trying to recollect that we were thinking of something entirely different. There are, then, two kinds of true memory—one in which the will intervenes, and which may be spoken of as _recollection_, and the other in which it does not, and which may be termed _reminiscence_. Neither of these can exist in a creature destitute of true self-consciousness. There are, however, two other kinds of repeated action which take place even in ourselves, and which should be carefully distinguished. The first of these are practically automatic actions, which are repeated unconsciously after having been learned, as in walking, reading, speaking, and often in playing some musical instrument. In a certain vague and improper sense we may be said—having learned how to do these things—to _recollect_ how to do them; but unless the mind recognises the past in the present while performing them they are not instances of memory, but merely a form of habit in which consciousness may or may not intervene.