thoughts and impressions, but as old ones, else I no longer remember, but only conceive or perceive.
III. Qualities of Memory.
Distinctions of Stewart and Wayland.—It has been customary to designate certain qualities as essential to a good memory. Susceptibility, retentiveness, and readiness, are thus distinguished by Mr. Stewart; the first denoting the facility with which the mind acquires; the second, the permanence with which it retains; and the third, the quickness with which it recalls and applies its original acquisitions. And these qualities are rarely united, he adds, in the same person. The memory which is susceptible and ready, is not commonly very retentive. Dr. Wayland makes the same distinction. Some men, he says, retain their knowledge more perfectly than they recall it. Others have their knowledge always at command. Some men acquire with great rapidity, but soon forget what they have learned. Others acquire with difficulty, but retain tenaciously.
Objections to this View.—Although supported by such authority, it admits of question whether this distinction is strictly valid. Facility of acquisition, the readiness with which the mind perceives truth, is hardly to be reckoned as an attribute of memory. It is a quality of mind, a quality possessed in diverse degrees by different persons, doubtless, but not a quality of mind in its distinctive capacity and office of remembering. It is no part, psychologically considered, of the function of mental reproduction. It is essential, indeed, to the act of memory that there should be something to remember, but the acquisition of the thing remembered, and the remembering, are two distinct and different mental acts; nor is it of any consequence to the mind, in remembering, whether the original acquisition was made with more or less facility. Indeed, so far as that bears upon the case at all, facility of acquisition, as even these writers admit, is likely to be rather a hindrance than a help to subsequent remembrance, since what is most readily acquired is not most readily recalled.
The Mind retentive in what Sense.—Nor is it altogether proper to speak of retentiveness as a quality of memory—a quality which may pertain to it in a greater or less degree in different cases. The truth is, all memory is retentive, or, more properly, retentiveness is itself memory. It is a quality of mind; a power or faculty possessed in different degrees by different persons; and the power which the mind possesses of retaining thus, wholly, or in part, what passes before it, is the faculty of memory. But in what sense does the mind retain anything which has once occupied its thoughts? Not, of course, in the sense in which a hook retains the hat and coat that are hung upon it, ready to be taken down when wanted. We are not to conceive of the mind as a convenient receptacle, in which may be stowed away all manner of old thoughts, sensations, impressions, as old clothes are put by in a press, or guns in an armory. Not in any such sense is the mind retentive. What we mean, when we say the mind is retentive, is simply this, that it is in its power to repossess itself of what has once passed before it, to regain a thought or impression it has once had. And this is done by the operation of those laws of suggestion already considered. That, and that only is retained by the mind, which under the appropriate circumstances is by the principle of suggestion recalled to the mind. We are not to distinguish, then, the power to retain and the power to recall, as two separate things; nor, for the same reason, can we conceive of a memory that is other than retentive, or that is retentive but not ready. So far as these expressions denote any real distinction, it amounts simply to this, that some minds are more retentive than others; in other words, more susceptible of the influence of the suggesting principle in recalling ideas that have once been before them. Such a difference undoubtedly exists. Some remember much more readily and extensively than others. This may be owing, partly, to some difference of mental constitution and endowment; but more frequently to differences of mental habit and culture. It is not necessary to refer again to the laws of mental reproduction which have been already discussed. It is sufficient to say, that the more clearly any fact or truth is originally apprehended, and the more deeply it interests the mind, the more readily will it subsequently recur and the longer will it be retained.
IV. Memory in Relation to Intellectual Strength
The common Opinion.—The question has arisen, how far the power of memory may be regarded as a test of intellectual ability. The opinion has been somewhat prevalent, that a more than usual development of this faculty is likely to be attended with a corresponding deficiency in some other mental power, and especially that it is incompatible with a sound judgment. To this opinion I cannot subscribe. Doubtless it is true that many persons, deficient in the power of accurate discrimination, have possessed wonderful power of memory. The mind, in such cases, undisciplined, uncultivated, with little inventive and self-moving power, lies passive and open to the influence of every chance suggestion from without, as the lyre is put in vibration by the stray winds that sweep across its strings. Facts and incidents of no value, without number, and without order, are thrown into relief upon the confused background of the past, as sea-weed, sand, and shells are heaped by the unmeaning waves upon the shore.
But if a weak mind may possess a good memory, it is equally true, that a strong and well disciplined mind is seldom deficient in it. Men of most active and commanding intellect have been men also of tenacious and accurate memory. Napoleon was a remarkable instance of this. So also was the philosopher Leibnitz. While, then, we cannot regard the memory as a test of intellectual capacity, neither can it be considered incompatible with, or unfavorable to, mental strength. On the contrary, we can hardly look for any considerable degree of mental vigor and power where this faculty is essentially deficient.
Memory as affected by the Art of Printing.—It is remarked by Miss Edgeworth, and the remark is noticed with approval by Dugald Stewart, that the invention of printing, by placing books within the reach of all classes of people, has lowered the value of those extraordinary powers of memory which some of the learned were accustomed to display in former times. A man who had read, and who could repeat, a few manuscripts, was then not merely a remarkable, but a very useful man. It is quite otherwise now. There is no occasion now for any such exercise of memory. Hence instances of extraordinary memory are of unfrequent occurrence.
Failure of Memory accompanies failure of mental Power.—A decline of mental vigor, whether produced by disease or age, is usually attended with loss of memory to some extent. The first symptoms of this failure are usually forgetfulness of proper names and dates, and sometimes of words in general. A stroke of palsy frequently produces this result, and in such cases the name sometimes suggests the object, while the object no longer recalls the name. This is probably owing to the fact that the sign, being of less consequence than the thing signified, and making less impression on the mind, is more readily forgotten; hence the name, if suggested, recalls the thing, while, at the same time, the thing may not recall the name. In general, we pass more readily from the sign to the thing signified, than the reverse, and for the reason now given. Mr. Steward remarks, that this loss of proper names incident to old men, is chiefly observable in men of science, or those much occupied with important affairs—a fact resulting, he thinks, partly from their habits of general thought, and partly from their want of constant practice in that trivial conversation which is every moment recalling particulars to the mind.
The Memory of the Aged.—In the principles which have been advanced, we find an explanation, I think, of some facts respecting memory, which every one has noticed, but of which the philosophy may not be at first sight apparent, Why is it that aged people forget? that, as we grow old, while perhaps other powers of the mind are still vigorous, the memory begins to lose its tenacity? Not, I suspect, from any special change which the brain undergoes, for why should such changes affect this faculty more than any other? I should seek the explanation in a failure of one or other of the conditions already mentioned as essential to a good memory; either in the want of a sufficiently frequent coëxistence of associated ideas, or else in the want of a sufficiently vivid conception of them when presented; or, more likely, in both. And so the facts would indicate. Age involves usually the gradual failure and decay of the powers of perception; the ear fails to report what is said, the eye what is passing in space; and as memory is dependent on prior perception, of course a diminished activity of the one brings
