effort made to guard against loss by degeneration and dissipation. It is found necessary to make a direct effort to store the memory and make it retentive. But even this effort is subject to much criticism, and every device is sought to avoid making a direct effort to memorize. Efforts to develop the more complex faculties rest satisfied with being directed toward the stimulation of activity, and little or no thought is given to the question of what becomes of it when produced.

(II.) To discover the methods by which dissipation may be prevented, we must know what forms of activity are most subject to it, and what direction of activity is toward degradation. These points will be taken up under the treatment of the various mental powers. Only the general Law of conservation will be treated of in this chapter.

LAW IV.-UNIFICATION OF DIFFERENCES IS CONSERVATION OF MENTAL ENERGY.

First Proof.-Unification has been shown to be necessary to development, but it must be a unification that preserves differences. The tendency to dissipation by unifying without preserving distinctions, is checked when the differences are held in the mind, and when the energy excited is used in fixing variety of forms of thought. The mind possesses power in proportion as it is able to bring a large number of activities to the understanding of truth.

Second Proof.-In making and holding discriminations clearly in mind under the forms of unities, the various powers of mind are exercised and developed, and the energy thus called into action results in the development of permanent strength.

OBSERVATIONS.

(I.) The importance of carrying through a purpose or an undertaking will be seen from this Law. The more perfectly discriminations are cemented together, the stronger the hold which the mind has on them.

(II.) Thorough classification is important for the conservation of energy. In this way differences are most firmly held together in the unities of thought, and the very fact of classification gives prominence to characteristic differences.

(III.) In this Law is seen the importance of clear analysis. It has been noted as a fact that the strong men of broad intellects prominent in history have been educated by methods that lead to the clearest and most careful analysis of thought. The development of a new thought into the clear apprehension of men has led to many a revolution in government, in warfare, in business, or in individual character. The United States government was founded upon a new idea. New ideas have determined the result of many of the decisive battles of the world. In the clear analysis of thought that brings out new views of truth lies the teacher's source of power. As has been said, he that discriminates well, teaches well. This is true both in respect to the development and to the conservation of power.

(IV.) The complete assimilation of discriminations in a unity is the culminating process of development. Analysis that is not followed by synthesis does not increase mental power. The two processes must go together. The habit of turning the attention from differences to unity, and from unity to differences until the whole is seen in all its parts, perfects the work of development. The practical difficulty to be overcome is that of holding com

plex unities with sufficient clearness to comprehend the relations of all the parts to the whole. In Arithmetic, for example, the elements that enter in to make up the answer required are set forth in the question; but if the conditions are complex, it is difficult for an untrained mind to hold them in consciousness so as to see their relation to the unity required. A repetition of processes till each step becomes almost automatic, is needed for completely comprehending such lines of reasoning. As a rule, the briefer and more distinct the representations of the elements and their relations, the easier the process of reasoning becomes. A fitting word, a technical term, or a sign is a great aid. A diagram that sets forth the essential unity of a sentence and the relations of all the parts at the same time, is a device of great value in Grammar when rightly used. If the real thought is first put into the diagram, the analyzed form will be more easily comprehended in this than in any other way.

2. In

As an illustration of the advantage of brevity, take the rule for dividing a fraction by a fraction. It may be stated in any one of three forms: 1. Multiply the numerator of the dividend by the denominator of the divisor for a new numerator, and the denominator of the dividend by the numerator of the divisor for a new denominator. vert the divisor and multiply. 3. Multiply the reciprocal of the divisor by the numerical dividend. In the first form the rule is perfectly plain, and yet it is difficult to keep every element distinctly in mind so as to comprehend the rule in one unity of thought. The second form of the rule presents every relation presented by the first form, and so briefly that it can easily be held in mind as a whole. But in the second form there is nothing to point out the course of thought. In the third form the reasoning process is clearly indicated in the briefest way, and if

we distinguish between a numerical dividend and a concrete fraction, the reasoning will apply equally well to a concrete and to an abstract number.

LAW V. THE TENDENCY TO DEGRADATION AND DISSIPATION IS INCREASED BY INDULGENCE.

Proof. To prove this Law, it is only necessary to refer to the growth of habits. If one acquires a habit of carelessness about keeping his promises or carrying out his resolutions, the energy of his thought, distinctly manifest in the promise or resolution, is dissipated; and the more frequently this occurs the harder it is to keep a promise or a resolution. The same weakening effect of habitual dissipation is manifest in every form of mental energy.

OBSERVATION.

It should not be necessary to urge any thing to enforce the importance of this Law. The basis on which the young are cautioned against the indulgence of evil habits, and most of them belong to one form of dissipation or another, is as strong as any physical law. The need is to realize the certainty of the Law and the innumerable ways in which it finds application.

CHAPTER VII.

SEQUENCE.

HE forms of mental activity succeed one

another in a fixed order.

We saw this

illustrated in studying the different mental faculties. There must be perception before

there can be memory, and there must be memory before there can be comparison. When a teacher observes the order in which a child's mind naturally develops in understanding, and presents truth in accordance with this order, he is said to follow the order of nature, not because nature presents truth in this order, but because the mind can develop only in this order. The different forms of truth are presented in an order corresponding to the order in which different forms of mental activity develop. From the infinite diversity of forms in which creative wisdom is manifested in nature, the mind selects only those that are adapted to its condition and stage of development. The teacher follows nature when he adapts himself to this necessity. To know the order in which truth must be presented, the mind must be studied and the laws of the succession of its activities observed.

LAW I.-THE FACULTIES OF THE MIND ARE DEVELOPED AND COME TO MATURITY IN THE ORDER OF THEIR DEPENDENCE ONE UPON ANOTHER.

First Proof-So constant and regular is the order of development, that the educational period may easily be