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down by the discovery of his deficiency in any elementary faculty of the mind. What tells in life is the whole mind working together, and the deficiencies of any one faculty can be compensated by the efforts of the rest. You can be an artist without visual images, a reader without eyes, a mass of erudition with a bad elementary memory. In almost any subject your passion for the subject will save you. If you only care enough for a result, you will almost certainly attain it. If you wish to be rich, you will be rich; if you wish to be learned, you will be learned; if you wish to be good, you will be good, Only you must, then, really wish these things, and wish them with exclusiveness, and not wish at the same time a hundred other incompatible things just as strongly.

One of the most important discoveries of the 'scientific' sort that have recently been made in psychology is that of Mr. Galton and others concerning the great variations among individuals in the type of their imagination. Every one is now familiar with the fact that human beings vary enormously in the brilliancy, completeness, definiteness, and extent of their visual images. These are singularly perfect in a large number of individuals, and in a few are so rudimentary as hardly

to exist. The same is true of the auditory and motor images, and probably of those of every kind; and the recent discovery of distinct brainareas for the various orders of sensation would seem to provide a physical basis for such variations and discrepancies. The facts, as I said, are nowadays so popularly known that I need only remind you of their existence. They might seem at first sight of practical importance to the teacher; and, indeed, teachers have been recommended to sort their pupils in this way, and treat them as the result falls out. You should interrogate them as to their imagery, it is said, or exhibit lists of written words to their eyes, and then sound similar lists in their ears, and see by which channel a child retains most words. Then, in dealing with that child, make your appeals predominantly through that channel. If the class were very small, results of some distinctness might doubtless thus be obtained by a pains taking teacher. But it is obvious that in the usual school-room no such differentiation of appeal is possible; and the only really useful practical lesson that emerges from this analytic psychology in the conduct of large schools is the lesson already reached in a purely empirical way, that

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the teacher ought always to impress the class through as many sensible channels as he can. Talk and write and draw on blackboard, permit the pupils to talk, and make them write and draw, exhibit pictures, plans, and curves, have have your diagrams colored differently in their different parts, etc.; and out of the whole variety of impressions the individual child will find the most lasting ones for himself. In all primary school work this principle of multiple impressions is well recognized, so I need say no more about it here.

This principle of multiplying channels and varying associations and appeals is important, not only for teaching pupils to remember, but for teaching them to understand. It runs, in fact, through the whole teaching art.

One word about the unconscious and unreproducible part of our acquisitions, and I shall have done with the topic of memory.

Professor Ebbinghaus, in a heroic little investigation into the laws of memory which he performed a dozen or more years ago by the method of learning lists of nonsense syllables, devised a method of measuring the rate of our forgetfulness, which lays bare an important law of the mind.

His method was to read over his list until he could repeat it once by heart unhesitatingly. The number of repetitions required for this was a measure of the difficulty of the learning in each particular case. Now, after having once learned a piece in this way, if we wait five minutes, we find it impossible to repeat it again in the same unhesitating manner. We must read it over again to revive some of the syllables, which have already dropped out or got transposed. Ebbinghaus now systematically studied the number of readingsover which were necessary to revive the unhesitating recollection of the piece after five minutes, half an hour, an hour, a day, a week, a month, had elapsed. The number of rereadings required he took to be a measure of the amount of forgetting that had occurred in the elapsed interval. And he found some remarkable facts. The process of forgetting, namely, is vastly more rapid at first than later on. Thus full half of the piece seems to be forgotten within the first half-hour, two-thirds of it are forgotten at the end of eight hours, but only four-fifths at the end of a month. He made no trials beyond one month of interval; but, if we ourselves prolong ideally the curve of remembrance, whose beginning his experiments

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thus obtain, it is natural to suppose that, no matter how long a time might elapse, the curve would never descend quite so low as to touch the zero-line. In other words, no matter how long ago we may have learned a poem, and no matter how complete our inability to reproduce it now may be, yet the first learning will still show its lingering effects in the abridgment of the time required for learning it again. In short, Professor Ebbinghaus's experiments show that things which we are quite unable definitely to recall have nevertheless impressed themselves, in some way, upon the structure of the mind. We are different for having once learned them. The resistances in our systems of brain-paths are altered. Our apprehensions are quickened. Our conclusions from certain premises are probably not just what they would be if those modifications were not there. The latter influence the whole margin of our consciousness, even though their products, not being distinctly reproducible, do not directly figure at the focus of the field.

The teacher should draw a lesson from these facts. We are all too apt to measure the gains of our pupils by their proficiency in directly reproducing in a recitation or an examination such