agsinet

this latter improvement is due to the way in which the things in question are woven into association with each other in the mind. Intricately or profoundly woven, they are held: disconnected, they tend to drop out just in proportion as the native brain retentiveness is poor. And no amount of training, drilling, repeating, and reciting employed upon the matter of one system of objects, the history-system, for example, will in the least improve either the facility or the durability with which objects belonging to a wholly disparate system -the system of facts of chemistry, for instance tend to be retained. That system must be separately worked into the mind by itself,— a chemical fact which is thought about in connection with the other chemical facts, tending then to stay, but otherwise easily dropping out.

We have, then, not so much a faculty of memory as many faculties of memory. We have as many as we have systems of objects habitually thought of in connection with each other. A given object is held in the memory by the associates it has acquired within its own system exclusively. Learning the facts of another system will in no wise help it to stay in the mind, for the simple

MEMORIES RATHER THAN MEMORY 125

reason that it has no cues' within that other

system.

We see examples of this on every hand. Most men have a good memory for facts connected with their own pursuits. A college athlete, who remains a dunce at his books, may amaze you by his knowledge of the 'records' at various feats and games, and prove himself a walking dictionary of sporting statistics. The reason is that he is constantly going over these things in his mind, and comparing and making series of them. They form for him, not so many odd facts, but a concept-system, so they stick. So the merchant remembers prices, the politician other politicians' speeches and votes, with a copiousness which astonishes outsiders, but which the amount of thinking they bestow on these subjects easily explains.

The great memory for facts which a Darwin or a Spencer reveal in their books is not incompatible with the possession on their part of a mind with only a middling degree of physiological retentiveness. Let a man early in life set himself the task of verifying such a theory as that of evolution, and facts will soon cluster and cling to him like grapes to their stem. Their relations to the

or a Summe

theory will hold them fast; and, the more of these the mind is able to discern, the greater the erudi. tion will become. Meanwhile the theorist may have little, if any, desultory memory. Unutilizable facts may be unnoted by him, and forgotten as soon as heard. An ignorance almost as encyclopedic as his erudition may coexist with the latter, and hide, as it were, within the interstices of its web. Those of you who have had much to do with scholars and savants will readily think of examples of the class of mind I mean.

The best possible sort of system into which tọ weave an object, mentally, is a rational system, or what is called a 'science.' Place the thing in its pigeon-hole in a classificatory series; explain it logically by its causes, and deduce from it its necessary effects; find out of what natural law it is an instance, and you then know it in the best of all possible ways. A science' is thus the greatest of labor-saving contrivances. It relieves the memory of an immense number of details, replacing, as it does, merely contiguous associations by the logical ones of identity, similarity, or analogy. If you know a law,' you may discharge your memory of masses of particular instances, for the law will reproduce them for you whenever

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127

you require them. The law of refraction, for example: If you know that, you can with a pencil and a bit of paper immediately discern how a convex lens, a concave lens, or a prism, must severally alter the appearance of an object. But, if you don't know the general law, you must charge your memory separately with each of the three kinds of effect.

A 'philosophic' system, in which all things found their rational explanation and were connected together as causes and effects, would be the perfect mnemonic system, in which the greatest economy of means would bring about the greatest richness of results. So that, if we have poor desultory memories, we can save ourselves by cultivating the philosophic turn of mind.

There are many artificial systems of mnemonics, some public, some sold as secrets. They are all so many devices for training us into certain methodical and stereotyped ways of thinking about the facts we seek to retain. Even were I competent, I could not here go into these systems in any detail. But a single example, from a popular system, will show what I mean. I take the numberalphabet, the great mnemonic device for recollecting numbers and dates. In this system each digit

is represented by a consonant, thus: 1 is t or d; 2, n; 3, m; 4, r; 5, l; 6, sh, j, ch, or g; 7, c, k, g, or qu; 8, ƒ or v; 9, b or p ; 0, 8, c, or z. Suppose, now, you wish to remember the velocity of sound, 1,142 feet a second: t, t, r, n, are the letters you must use. They make the consonants of tight run, and it would be a tight run' for you to keep up such a speed. So 1649, the date of the execution of Charles I., may be remembered by the word sharp, which recalls the headsman's

axe.

6

6

Apart from the extreme difficulty of finding words that are appropriate in this exercise, it is clearly an excessively poor, trivial, and silly way of thinking' about dates; and the way of the historian is much better. He has a lot of landmark-dates already in his mind. He knows the historic concatenation of events, and can usually place an event at its right date in the chronologytable, by thinking of it in a rational way, referring it to its antecedents, tracing its concomitants and consequences, and thus ciphering out its date by connecting it with theirs. The artificial memorysystems, recommending, as they do, such irrational methods of thinking, are only to be recommended for the first landmarks in a system, or for such