[[4]] "The Principles of Argumentation" by Baker and Huntington, is another excellent book, not treating of formal logic, but discussing the general principles which should govern the preparation of a paper or argument, the principles of evidence, and the logical fallacies in reasoning. It is recommended to readers. This book is, or has been, used in the course in English at Harvard University, and similar books are used in other colleges. A thorough training in English under a good teacher is a good training in logic, for clear and logical writing requires clear and logical thinking. Nevertheless, the writer strongly advocates the study of formal logic also.
[[5]] "It is not enough to know, we must also apply; it is not enough to will, we must also do."—Goethe.
III
THE THIRD ESSENTIAL FOR A PROPER METHOD OF STUDY IS SYSTEM
(a) DISCOVER THE FUNDAMENTAL IDEA OF THE SUBJECT.—Strip off the detail and get down to the root of the thing. See the really important point. Then, after this has been clearly perceived and mastered, arrange the details in their proper relations to the fundamentals. The subject will thus have a skeleton, and upon this the details will be placed. A subject of study thus viewed may be compared to the human body, with its bony skeleton or framework, and all the various organs and parts supported by it; or to a tree, with its trunk, branches and leaves. Thus to consider the relative importance of facts, to sift out the essential ones, will train the power of mental discrimination and cultivate the judgment.
When this is done, subsequent facts relating to the subject can be correlated with what is already known, and will in this way be easily retained by the memory. Remember and observe Jacotot's maxim, "Learn something accurately, and refer the rest to that." Unessential facts, or those of secondary importance, may be passed over in the first reading, and left for a second or later reading, for a proper method of study always involves re-reading, perhaps many times.
You cannot possibly know everything even of a single subject, hence the importance of knowing the fundamental things about it and knowing them thoroughly. Even if you gain but an elementary knowledge of a subject, that knowledge may be thorough and should include fundamentals. Thorough elementary knowledge must not be confused with a smattering. The latter is worse than useless, and is marked by vagueness, uncertainty, and failure to grasp fundamentals. But elementary knowledge, if clear and definite as far as it goes, is valuable, and the first step toward more complete knowledge. Many students deceive themselves and others into thinking that they know something of a subject, because they have looked into it, while their knowledge may be entirely superficial and valueless.