This matter of association by relation is one of the most important things in the whole subject of thought, and the degree of correct and efficient thinking depends materially upon it. It does not suffice us to merely "know" a thing—we must know where to find it when we want it. As old Judge Sharswood, of Pennsylvania, once said: "It is not so much to know the law, as to know where to find it." Kay says: "Over the associations formed by contiguity in time or space we have but little control. They are in a manner accidental, depending upon the order in which the objects present themselves to the mind. On the other hand, association by similarity is largely put in our own power; for we, in a measure, select those objects that are to be associated, and bring them together in the mind. We must be careful, however, only to associate together such things as we wish to be associated together and to recall each other; and the associations we form should be based on fundamental and essential, and not upon mere superficial or casual resemblances. When things are associated by their accidental, and not by their essential qualities,—by their superficial, and not by their fundamental relations, they will not be available when wanted, and will be of little real use. When we associate what is new with what most nearly resembles it in the mind already, we give it its proper place in our fabric of thought. By means of association by similarity, we tie up our ideas, as it were, in separate bundles, and it is of the utmost importance that all the ideas that most nearly resemble each other be in one bundle."
The best way to acquire correct associations, and many of them, for a separate fact that you wish to store away so that it may be recollected when needed—some useful bit of information or interesting bit of knowledge, that "may come in handy" later on—is to analyze it and its relations. This may be done by asking yourself questions about it—each thing that you associate it with in your answers being just one additional "cross-index" whereby you may find it readily when you want it. As Kay says: "The principle of asking questions and obtaining answers to them, may be said to characterize all intellectual effort." This is the method by which Socrates and Plato drew out the knowledge of their pupils, filling in the gaps and attaching new facts to those already known. When you wish to so consider a fact, ask yourself the following questions about it:
| I. | Where did it come from or originate? |
| II. | What caused it? |
| III. | What history or record has it? |
| IV. | What are its attributes, qualities and characteristics? |
| V. | What things can I most readily associate with it? What is it like? |
| VI. | What is it good for—how may it be used—what can I do with it? |
| VII. | What does it prove—what can be deduced from it? |
| VIII. | What are its natural results—what happens because of it? |
| IX. | What is its future; and its natural or probable end or finish? |
| X. | What do I think of it, on the whole—what are my general impressions regarding it? |
| XI. | What do I know about it, in the way of general information? |
| XII. | What have I heard about it, and from whom, and when? |
If you will take the trouble to put any "fact" through the above rigid examination, you will not only attach it to hundreds of convenient and familiar other facts, so that you will remember it readily upon occasion, but you will also create a new subject of general information in your mind of which this particular fact will be the central thought. Similar systems of analysis have been published and sold by various teachers, at high prices—and many men have considered that the results justified the expenditure. So do not pass it by lightly.
The more other facts that you manage to associate with any one fact, the more pegs will you have to hang your facts upon—the more "loose ends" will you have whereby to pull that fact into the field of consciousness—the more cross indexes will you have whereby you may "run down" the fact when you need it. The more associations you attach to a fact, the more "meaning" does that fact have for you, and the more interest will be created regarding it in your mind. Moreover, by so doing, you make very probable the "automatic" or involuntary recollection of that fact when you are thinking of some of its associated subjects; that is, it will come into your mind naturally in connection with something else—in a "that reminds me" fashion. And the oftener that you are involuntarily "reminded" of it, the clearer and deeper does its impression become on the records of your memory. The oftener you use a fact, the easier does it become to recall it when needed. The favorite pen of a man is always at his hand in a remembered position, while the less used eraser or similar thing has to be searched for, often without success. And the more associations that you bestow upon a fact, the oftener is it likely to be used.
Another point to be remembered is that the future association of a fact depends very much upon your system of filing away facts. If you will think of this when endeavoring to store away a fact for future reference, you will be very apt to find the best mental pigeon-hole for it. File it away with the thing it most resembles, or to which it has the most familiar relationship. The child does this, involuntarily—it is nature's own way. For instance, the child sees a zebra, it files away that animal as "a donkey with stripes;" a giraffe as a "long-necked horse;" a camel as a "horse with long, crooked legs, long neck and humps on its back." The child always attaches its new knowledge or fact on to some familiar fact or bit of knowledge—sometimes the result is startling, but the child remembers by means of it nevertheless. The grown up children will do well to build similar connecting links of memory. Attach the new thing to some old familiar thing. It is easy when you once have the knack of it. The table of questions given a little farther back will bring to mind many connecting links. Use them.
If you need any proof of the importance of association by relation, and of the laws governing its action, you have but to recall the ordinary "train of thought" or "chain of images" in the mind, of which we become conscious when we are day-dreaming or indulging in reverie, or even in general thought regarding any subject. You will see that every mental image or idea, or recollection is associated with and connected to the preceding thought and the one following it. It is a chain that is endless, until something breaks into the subject from outside. A fact flashes into your mind, apparently from space and without any reference to anything else. In such cases you will find that it occurs either because you had previously set your subconscious mentality at work upon some problem, or bit of recollection, and the flash was the belated and delayed result; or else that the fact came into your mind because of its association with some other fact, which in turn came from a precedent one, and so on. You hear a distant railroad whistle and you think of a train; then of a journey; then of some distant place; then of some one in that place; then of some event in the life of that person; then of a similar event in the life of another person; then of that other