+154. Clear Understanding.+—The first requisite of a good explanation is a clear understanding on the part of the one who is giving the explanation. It is evident that if we do not understand a subject ourselves we cannot make our explanations clear to others. If the ideas in our mind are in a confused state, our explanation will be equally confused. If you do not understand a problem in algebra, your attempt to explain it to others will prove a failure. If you attempt to explain how a canal boat is taken through a lock without thoroughly understanding the process yourself, you will give your listeners only a confused idea of how it is done.
The principal reason why pupils fail in their recitations and examinations is that in preparing their lessons, they do not make themselves thoroughly acquainted with the topics that they are studying. They often go over the lessons hurriedly and carelessly and come to class with confused ideas. Consequently when the pupils attempt to recite, there is, if anything, an additional confusion of ideas, and the recitation proves a failure. Carelessness in the preparation of daily recitations, negligence in asking for additional explanations, and inattention to the explanations that are given, inevitably cause failure when tests or examinations are called for.
EXERCISES
1. Name five subjects about which you know so little that it would be useless to attempt an explanation.
2. Name five about which you know something, but not enough to give clear explanations of them.
3. Name four about which you know but little, but concerning which you feel sure that you can obtain information.
4. Name six that you think you clearly understand. Report orally on one of them.
+Theme LXXXIV.+—Write out an explanation of one of the subjects named in number four of the preceding exercise.
(Read your theme and criticise it as to clearness. In listening to the themes read by other members of the class consider them as to clearness. Call for further explanation of any part not perfectly clear to you.)
+155. Selection of Facts—Unity.+—After we have been given a subject for explanation or have chosen one for ourselves, we must decide concerning the facts to be presented. In some kinds of exposition this selection is rather difficult. Since the purpose is to make our meaning clear to the person addressed, we secure unity by including all that is necessary to that purpose and by omitting all that is not necessary. It is evident that selection of facts to secure unity depends to some extent upon the audience. If a child asks us to explain what a trust is, our explanation will differ very much from that which we would give if we were addressing a body of men who were familiar with the term trusts, but do not understand the advantages and disadvantages arising from their existence.