tined to extend the boundaries of science, when they first. enter on new pursuits, feel their attention distracted and their memory overloaded with facts, among which they can trace no relation, and are sometimes apt to despair entirely of their future progress. In due time, however, their superiority appears, and arises in part from that very dissatisfaction which they at first experienced, and which does not cease to stimulate their inquiries, till they are enabled to trace, amid a chaos of apparently unconnected materials, that simplicity and beauty which always characterize the operations of nature."

§ 251. Further illustrations of philosophic memory.

Mr. Stewart pursues this train of remark further, maintaining, as a general thing, that a man of genius has his knowledge less at command than those who are possessed of an inferior degree of originality, and particularly in respect to those subjects on which he has found his originality and invention most fertile. And in this connexion he mentions the case of Sir Isaac Newton in terms as follows: "Sir Isaac Newton (as we are told by Dr. Pemberton) was often at a loss when the conversation turned on his own discoveries. It is probable that they made but a slight impression on his mind, and that a consciousness of his inventive powers prevented him from taking much pains to treasure them up in his memory.Men of little ingenuity seldom forget the ideas they acquire, because they know that, when an occasion occurs for applying their knowledge to use, they must trust to memory and not to invention. Explain an arithmetical rule to a person of common understanding who is unacquainted with the principles of the science; he will soon get the rule by heart, and become dexterous in the application of it. Another, of more ingenuity, will examine the principle of the rule before he applies it to use, and will scarcely take the trouble to commit to memory a process which he knows he can at any time, with a little reflection, recover. The consequence will be, that, in the practice of calculation, he will appear more slow and hesitating than if he followed the received rules of arithmetic without reflection or reasoning.

"Something of the same kind happens every day in conversation. By far the greater part of the opinions we announce in it are not the immediate result of reasoning on the spot, but have been previously formed in the closet, or, perhaps, have been adopted implicitly on the authority of others. The promptitude, therefore, with which a man decides in ordinary discourse, is not a certain test of the quickness of his apprehension, as it may perhaps arise from those uncommon efforts to furnish the memory with acquired knowledge, by which men of slow parts endeavour to compensate for their want of invention; while, on the other hand, it is possible that a consciousness of originality may give rise to a manner apparently embarrassed, by leading the person who feels it to trust too much to extempore exertions."

§ 252. Of that species of memory called intentional recollection. There is a species or exercise of the memory, known as INTENTIONAL RECOLLECTION, the explanation of which renders it proper briefly to recur again to the nature of memory in general. The definition of MEMORY which has been given is, that it is the power or susceptibility of the mind by which those conceptions are originated, which are modified by the perception of the relation of past time. This definition necessarily resolves memory, in a considerable degree at least, into Association. But it will be recollected that our trains of associated thought are not, in the strict sense, voluntary; that is, are not directly under the control of the WILL. They come and depart (we speak now exclusively of their origination) without its being possible for us to exercise anything more than an INDIRECT power over them. (See § 242.) It follows, from these facts, that our remembrances also, which may be regarded in part as merely associated trains, are not, in the strict sense, voluntary; or, in other words, it is impossible for us to remember in consequence of merely choosing to remember. To will or to choose to remember anything implies that the thing in question is already in the mind; and hence there is not only an impossibility resulting from the nature of the mind, but also an absurdity in the idea of calling up thought by a mere

direct volition. Our chief power, therefore, in quickening and strengthening the memory, will be found to consist in our skill in applying and modifying the various principles or laws of association. And this brings us to an explanation of what is called INTENTIONAL MEMORY Or RECOLLECTION; a subject which was partly illustrated in the section above referred to.

Whenever we put forth an exercise of intentional memory, or make a formal attempt to remember some circumstance, it is evident that the event in general, of which the circumstance, when recalled, will be found to be a part, must have previously been an object of attention. That is, we remember the great outlines of some story, but cannot, in the first instance, give a complete account of it, which we wish to do. We make an effort to recall the circumstances not remembered in two ways.-We may, in the first place, form different suppositions, and see which agrees best with the general outlines; the general features or outlines of the subject being detained before us, with a considerable degree of permanency, by means of some feeling of desire or interest. This method of restoring thoughts is rather an inference of reasoning than a genuine exercise of memory.

We may, in the second place, merely delay upon those thoughts which we already hold possession of; and revolve them in our minds, until, aided by some principle of association, we are able to lay hold of the particular ideas for which we were searching. Thus, when we endeavour to recite what we had previously committed to memory, but are at a loss for a particular passage, we repeat a number of times the concluding words of the preceding sentence. In this way the sentence which was forgotten is very frequently recalled.

253. Instance illustrative of the preceding.

The subject of the preceding section will perhaps be more distinctly understood in connexion with the following illustration. Dr. Beattie informs us, that he was himself acquainted with a clergyman, who, on being attacked with a fit of apoplexy, was found to have forgotten all the transactions of the four years immediately preceding

the attack. And yet he remembered as well as ever what had happened before that period. The newspapers which were printed during the period mentioned were read with interest, and afforded him a great deal of amusement, being entirely new to him. It is further stated, that this individual recovered by degrees all he had lost; so as, after a while, to have nearly or quite as full a remembrance of that period as others. In this instance the power of the principles of association appears to have been at first completely prostrated by the disease, without any prospect of their being again brought into action, except by some assistance afforded them. This assistance, no doubt, was conversation, the renewed notice of various external objects addressed to the senses, and reading. By reading old newspapers, and by conversation in particular, he occasionally fell upon ideas which he had not only been possessed of before, but which had been associated with other ideas, forming originally distinct and condensed trains of thought. And thus whole series were restored. -Other series, again, were recovered by applying the methods of INTENTIONAL RECOLLECTION; that is, by forming suppositions and comparing them with the ideas already recovered, or by voluntarily delaying upon and revolving in mind such trains as were restored, and thus rousing up others. Such we can hardly doubt to have been, in the main, the process by which the person of whom we are speaking recovered the knowledge he had lost.

These views, in addition to what has now been said, may be illustrated also by what we sometimes observe in old men. Question them as to the events of early life, and at times they will be unable to give any answer whatever. But, whenever you mention some prominent incident of their young days, or perhaps some friend on whom many associations have gathered, it will often be found that their memory revives, and that they are able to state many things, in respect to which they were previously silent.

254. Remarks on the memory of the aged.

In noticing the interesting aspects which the memory presents to our consideration, it may be proper to delay a

moment on the memory of the aged. And here the leading remark is, that a weakness of memory, a slowness and inability of recollection, exists in such persons. This weakness of remembrance, which is so frequently observed in men of advanced age, appears to be owing to two causes, viz., the impaired state of the organs of perception, and a defect of attention.

(1.) Their organs of external perception are impaired. We find it difficult, in consequence of the failure of their sense of hearing, to converse with people advanced in years, and it requires a great effort, both on our part and theirs, to make them understand what we say. The most conclusive arguments, and flashes of wit, and rich strains of music, have in a great measure ceased to attract their notice.There is a like failure of the sense of seeing also. They no longer take pleasure in the delightful aspects of creation. The waving forest, the blooming field, the gay beams of the sun, all the charming varieties and aspects of nature, although they have not ceased to have charms for others, have but little or none for them. The natural and necessary consequence of this state of things is, that the ideas, which are let in by the senses, make but a very feeble impression, and are almost immediately erased from the mind.

(2.) The second cause of the weakness of memory, of which old people complain, is a defect in attention.— That mental state to which we give the name of Attention, always implies, in a greater or less degree, an emotion of interest; and, without some feeling of this kind, it does not well appear how it could exist. But the world (including in the term what is beautiful in nature, and what is important in the duties and callings of life) has at last ceased to excite the emotions which it formerly awakened. The aged are like the prisoner, released in the period of the French revolution from the Bastile; they find themselves, as it were, in a new creation, which passes before them with great indistinctness, and with which they feel but little sympathy. As their organs of external perception have failed them, and as there has also been a defect of attention, the memory, as a natural consequence, has become broken and powerless.