EXERCISE
Which of the following are exact?
1. A sheep is a gregarious animal that produces wool.
2. A squash is a garden plant much liked by striped bugs.
3. A pronoun is a word used for a noun.
4. The diaphragm is a sheet of muscle and tendon, convex on its upper side, and attached by bands of striped muscle to the lower ribs at the side, to the sternum, and to the cartilage of the ribs which join it in front, and at the back by very strong bands to the lumbar vertebrae.
5. A man is a two-legged animal without feathers.
6. Argument is that form of discourse which has for its object the proof of the truth or falsity of a proposition.
7. The base of an isosceles triangle is that side which is equal to no other.
8. Zinc is a metal used under stoves.
9. The epidermis of a leaf is a delicate, transparent skin which covers the whole leaf.
+Theme LXXXVIII.+—Write an expository paragraph about one of the following:—
Suggested subjects:— 1. Household science and arts. 2. Architecture. 3. Aesthetics. 4. Poetry. 5. Fiction. 6. Half tones. 7. Steam fitting. 8. Swimming.
(Consider the definitions you have used.)
+162. Division.+—The second step in the exposition of a term is division. Definition establishes the limits of the term. Division separates into its parts that which is included by the term. By definition we distinguish triangles from squares, circles, and other plane figures. By division we may separate them into scalene, isosceles, and equilateral, or if we divide them according to a different principle into right and oblique triangles. In either case the division is complete and exact. By completeness is meant that every object denoted by the term explained is included in the division given, thus making the sum of these divisions equal to the whole. By exactness is meant that but a single principle has been used, and so no object denoted by the term explained will be included in more than one of the divisions made. There are no triangles which are neither right nor oblique, so the division is complete; and no triangle can be both right and oblique, so the division is exact. Such a complete and exact division is called classification.
Nearly every term may be divided according to more than one principle. We may divide the term books into ancient and modern, or into religious and secular, or in any one of a dozen other ways. Which principle of division we shall choose will depend upon our purpose. If we wish to discuss sponges with reference to their shapes, our division will be different from what it would be if we were to discuss them with reference to their uses. When a principle of division has once been chosen it is essential that it be followed throughout. The use of two principles causes an overlapping of divisions, thus producing what is called cross division. Using the principle of use, a tailor may sort his bolts of cloth into cloth for overcoats, cloth for suits, and cloth for trousers; using the principle of weight, into heavy weight and light weight; or he may sort them with reference to color or price. In any case but a single principle is used. It would not do to divide them into cloth for suits, light weight goods, and brown cloth. Such a division would be neither complete nor exact; for some of the cloth would belong to none of the classes while other pieces might properly be placed in all three.
In the exact sciences complete exposition is the aim, and classification is necessary; but in other writing the purpose in hand is often better accomplished by omitting minor divisions. A writer of history might consider the political growth, the wars, and the religion of a nation and omit its domestic life and educational progress, especially if these did not greatly influence the result that he wishes to make plain. If we wished to explain the plan of the organization of a high school, it would be satisfactory to divide the pupils into freshmen, sophomores, juniors, and seniors, even though, in any particular school, there might be a few special and irregular pupils who belonged to none of these classes. An exposition of the use of hammers would omit many occasional and unimportant uses. Such a classification though exact is incomplete and is called partition.