when it becomes a permanent form; but the energy expended on a form beyond what is required to make it permanent is so much exhausted from what might be used by establishing other forms and giving greater breadth.

OBSERVATIONS.

(I.) This Law is important in itself, as we would avoid narrowness of intelligence and capability. The greater the variety of forms of activity the greater will be the susceptibility to different forms of stimulus, and the mind will be the better prepared to seize upon chance opportunities for information or gaining other advantage. Many things are taught which seem to the young to have no bearing on life's work, and it is quite the custom to sneer at such things as only good for mental discipline. But we can never know beforehand what use may be made of a piece of knowledge. The application of the truths. we learn is much broader than the facts from which we learn them, and how much broader we shall never know. We are continually finding unexpected uses for our knowledge, and sometimes the most important help comes. from sources least considered. A boy that has grown up the terror of the community may, by his very temerity, be the salvation of the community in an emergency of fire or flood, in riot or in war. As few men can be spared to a community without some loss, so there are few truths which we may know that do not have practical value sometimes.

(II.) The Law is seen to be still further important when taken in connection with the Laws of correlation. The greater the variety of activities the greater will be the energy that may be concentrated upon a single object.

(III.) When we take the Law in connection with the

Laws of sequence we shall see its importance in securing a variety of fundamental truths, from which one is taken here and another there for the development of more advanced thoughts. When the child has advanced to that period of life at which he takes up a science, he can not afford to go back and learn by experience every fact he needs to use. These should be mostly learned at an earlier age, and with those needed for the science many more will be learned of necessity.

LAW II. STRENGTH IS GAINED BY THE GREATEST AMOUNT OF EXERCISE CONSISTENT WITH PERFECT RECUPERATION.

First Proof.-As in the case of the preceding Law the application to the increase of physical strength is easy. Tissues that are worn away are replaced by other material of finer and firmer character with every change that comes from healthy action, and the brain cells are connected together by new filaments making it possible to bring a larger amount of nerve force for the exercise of any one thought, and to sustain a single thought longer without fatigue.

Second Proof.-In the unification of several thoughts exercise gives the mind power to grasp and hold under control of the will unities containing more and more differences, and thus take a more comprehensive view of truth.

OBSERVATIONS.

(I.) In order to strengthen a muscle it must be severely exercised in every fiber. This requires the adaptation of exercise to the muscle. By such exercise the arm of the blacksmith, the limbs of the athlete, and the fingers of the

pianist, develop a strength hardly supposed possible by one who has never witnessed such changes. By adaptation of exercises the weak little finger may be made to give as firm a touch as any finger of the hand. The faculties of the mind may be improved in a similar way. Memory, judgment, and the will are at least as susceptible to improvement as the little finger. Fitting exercises should be given to each faculty.

(II.) The exercise required to develop strength is severe exercise. It should involve the largest number of discriminations which the mind can hold under unity with distinctness. Exercises which require little effort do not strengthen the mind. They may increase activity, but severe exercise alone calls out strength and builds up character.

LAW III. SKILL IS GAINED BY A REPETITION OF THE SAME EXERCISE OR SET OF EXERCISES WITH THE LEAST VARIATION.

First Proof.-When a physical action is repeated a habit is formed, and the action can be performed each time with less effort than before. This is not only physical skill, it is also mental. It may be that the nerve connections are shortened or made to conduct the nervous energy with less waste. But, whatever the cause, the mind gains an easier control of muscular activity by a repetition of the same act. If the act were repeated each time with differences the energy would be divided and the attention disturbed, and development of skill would be slow.

Second Proof.-Skill or facility, in purely mental operations, as in adding figures, is produced in the same way, by a repetition of the same processes. The same is true

of each of the mental faculties.

OBSERVATIONS.

(I.) If one desires skill in a particular thing the limits of variety should be determined, and the activities should include this variety, and one order should be maintained in every repetition of the exercise.

(II.) Division of labor is favorable to the cultivation of skill in workmanship, and the confining of the attention to a limited range of thought is conducive to skill in mental operations.

(III.) Breadth, strength, and skill are, in some degree, inconsistent with each other. To secure the highest degree of one is inconsistent with the highest perfection of the others. We may see this in the results of a great division of labor. Skill is acquired for one thing, but devotion to this exhausts the energy that might otherwise have developed broad views and a strong character. A versatile man is not likely to be a profound thinker, nor skillful in any one thing. There should be an effort to keep a fair balance in respect to these three results of exercise. Circumstances may determine that one of them should be sought more than the others, but in any case strength should not be sacrificed. This is a medium between the other two, and it is never wanting in the best class of minds.

CHAPTER X.

LIMITATIONS.

T is common to speak of the mind as unlimited in its power. It may be that it is capable of endless progress; but this does not imply that its attainments will not al

ways be finite. If the steps of a journey were infinitesimal, and the time for each one finite, it would require infinite time to complete the journey, limited though it might be. The steps the mind makes in the comprehension of truth are infinitesimal when compared with the whole of truth, and a comparatively long time is required for each step. But life is short, and the opportunities of any one individual to learn the truth are few, so that we are shut in within a very narrow limit of possibilities. The limitations resulting from the dependence of the mind upon the body have been sufficiently treated of under Physiological Relations, and those discussions do not need to be repeated here.

LAW I. THE MIND IS LIMITED BY A LIMITATION IN THE NUMBER OF ITS FACULTIES.

First Proof-The sense of sight is adapted to distinguish vibrations of a certain character and degree of rapidity. The ear discovers other kinds of vibrations. Other kinds, still, manifest themselves as electricity. But we know there are other kinds of vibrations, as the chem