whether by the diagram or by the simile Darwin had recourse to that curious immediate, almost physical sense of relation which accompanies every thorough understanding of a subject.

Generally, as I have said, the metaphor which sums up a long course of thought will be reduced to a single word or phrase which explains itself. But when the word has been so long used that the sense of its original figurative meaning has been blurred or rubbed out, as in such cases as classical, poetry, democratic, relation, and most of the commonest general words, then the only safe way is carefully to give your own definition. Most people do their thinking in these vague and inexact terms, which express at best not much more than hazy intentions of ideas. Matthew Arnold was the great exemplar of the definition of terms; he, writing criticism, of necessity used many terms like the grand style, culture, high seriousness. Such terms as these, which, as perhaps he did not always perceive, are in the last analysis terms of commendation-statements that you like or do not like a thing—are for purposes of explanation dangerous since they will be understood by different people in different ways and will be taken as applying to various objects. But see the care with which he uses such a phrase; he speaks of the grand style thus 1:

"The grand style arises in poetry when a noble nature, poetically gifted, treats with simplicity or with severity a

1 Quoted in A. S. Hill's " Principles of Rhetoric," p. 320.

serious subject. I think this definition will be found to cover all instances of the grand style in poetry which present themselves. I think it will be found to exclude all poetry which is not in the grand style. And I think it contains no terms which are obscure, which themselves need defining."

Though it may be questioned whether such terms as noble, simplicity, severity, always mean the same thing to all minds, it is safe to say that if ever such a term as grand style can be fixed by definition, it is so fixed here. At any rate, Arnold's tests have become noted; and they are of very practical service in writing explanations. If you are using a treacherous general term, ask yourself whether it covers all the specific facts for which you use it, whether it excludes all other facts, and whether in itself it contains terms which can be misunderstood by any rational reader.

In practice use general terms in exposition when they will sum up a long process of thought in a single phrase, and will make your reader see the subject swiftly and immediately; but in using them remember always that they are treacherous; that they carry so many ulterior implications both of thought and feeling, that you yourself may be led astray in using them; and, moreover, that they put you at the mercy of careless readers.

17. The other danger in explanation, of being more abstract than is necessary, and so letting your explanation slip by your readers' minds, is apt to arise

in two ways: in the first place, in the case of the great thinkers whose intellectual powers work, as it were, by leaps and flights; in the other extreme, from people who are too lazy to think their subject out in specific detail. Of the former class metaphysics is full of examples, such as Kant's "Critique of Pure Reason;" such men do not concern us here. The other class, the people who out of mere laziness write in general abstract terms, are common enough; for it is much easier to write on an abstract subject in the hackneyed general terms which lie ready at every one's service than to make your own generalizations fresh from the facts of your own experience of life. It is only the man who can think clearly who is not afraid to think hard, and to test his thought by the actual facts of experience. It is a great deal easier, for example, to devise an ideal scheme of education in general than it is to sit down and work out a series of courses which will be practicable for the five days of five hours each in grammar and high schools. Moreover, it is to be remembered that the object of all explanation is to satisfy the irrepressible instinct of man to understand his universe; and this universe is made up, not of hazy abstractions, but of hard and concrete facts. The men who have added to this understanding of the world have been the men who have made it possible to see more of the meaning of the real things of the world: men like Newton, who showed that the sun and the moon and the stars obey the same law as the falling stone; men like Franklin

and his successors in electricity, who have brought together the thunderbolt and the crackling when you rub a cat's back; men like Tyndall, who have made it a matter of common knowledge that the physical sensations which we call heat and light are bound up in a common origin and controlled by common laws. Indeed, it is not one of the least achievements of the nineteenth century that it has recognized that the real advances in thought are made not so much by the men of agile logical power as by the men who have stuck patiently to the obstinate facts of the concrete world. Accordingly, in all your explanations, whether your subject be baseball or the nebular hypothesis or a town government or the latest research in history, bear in mind that the ultimate value of your explanation will be its power to help people to order and simplify their real experience. Your explanation of baseball will seem merely perfunctory unless it makes people who read it see the essential character of the game, the special skill of a good player, and what there is in it to make such crowds of people willing to spend time and money to see it and your treatise in history will be vain and unprofitable unless by patient labor in absorbing facts you throw new light on the course of actual, concrete events. As Professor Lamont points out, "abstractions produce little or no effect until translated into concrete terms. If the writer himself does not translate them, the reader must; and this task makes hard reading." In general, the more abstract your explanation the fewer people will take the

trouble to read it. Why should you, when you undertake to make an explanation, throw on your reader the labor of applying your principles to realities?

Moreover, unless you give examples of the facts on which you base your explanation, you have no assurance that your reader may not apply your meaning to an entirely different set of facts. Your real object, especially if your explanation have any argumentative purpose, is to make him look at the facts which you are explaining in the same way that you do. Green's "Short History of England" is throughout a notable example of this use of specific facts in explanation, a method of which Macaulay was the first famous exemplar. So Mr. Bryce1 illustrates the conflict between national and state authority by telling of a sheriff in California who, in obedience to the state law, cut off the queue of a Chinese prisoner, Ho Ah Kow, and who later suffered judgment in a suit brought before the Federal court. And Mill in his "Political Economy" makes up instances of supposititious velvet manufacturers or bricklayers by whom he can test and make concrete the abstract proposition which he is working out. In all these cases not only do the writers make their exposition easier to read, but they make it more thorough and more lucid.

Both these dangers, then, the danger of ambiguity in the use of general terms, and the danger of undue abstraction, lie chiefly in the tendency of lazy thinkers to deal in somebody else's general terms rather than

1 "American Commonwealth," New York, 1893, vol. i. p. 331.