From F. Ramsey Fowler, ed., Little Brown Handbook (Boston: Little Brown, 1980), pp. 484-486.
The ability to summarize effectively--to strip a paragraph or a
chapter down to its central meaning without distorting the author's
original thought and approach--is extremely useful. Writing such
summaries is an excellent way to study. Having such summaries
available is invaluable for later reference and review.
Preparing summaries can also help you to read with greater accuracy and to write with greater conciseness and directness. You cannot summarize effectively if you have not read carefully, discriminating between principal and subordinate ideas. Such discrimination, in turn, will help you to sharpen your own style and to avoid the wordiness that creeps into careless writing.
Before you try to summarize a passage, read it carefully to discover the author's purpose and point of view. As you read, pick out the central ideas and notice how they are arranged. Be on the lookout for the author's own compact summaries, either at the beginning or end of a passage or at points of transition.
After studying the passage, you are ready to organize your summary, or précis. Ordinarily you will be able to reduce a paragraph--or sometimes a whole group of paragraphs--to a single sentence. Very complex paragraphs, however, may require more than one sentence.
Use a simple or complex sentence rather than a compound sentence to summarize a paragraph--unless the original paragraph itself is poorly organized. A compound sentence implies that there are two or more equally dominant ideas in the paragraph. If you find that you have written a compound summarizing sentence, recheck the paragraph to make sure that the author did not imply some subordinating relationship that you have missed. In determining the author's intent, be alert to such writing techniques as parallel clauses and phrases, which indicate ideas of equal weight, and transitional words and phrases, which show relationships among ideas.
Summarize the author's ideas in the order in which they have been presented, but avoid following the exact wording too closely. If you are overly scrupulous in trying to preserve the flavor of the original, your summary will be far too long. Do not hesitate, however, to pick up the author's key terms and phrases, for they are useful in binding the précis together. Discard any figures of speech, digressions, or discussions that are not essential to the "trunk and main branches." When you are all through, you should find that you have reduced the material to not over one-third of its original length. Study the following example:
We very rarely consider, however, the process by which we gained our convictions. If we did so, we could hardly fail to see that there was usually little ground for our confidence in them. Here and there, in this department of knowledge or that, some one of us might make a fair claim to have taken some trouble to get correct ideas of, let us say, the situation in Russia, the sources of our food supply, the origin of the Constitution, the revision of the tariff, the policy of the Holy Roman Apostolic Church, modern business organization, trade unions, birth control, socialism, the League of Nations, the excess profits tax, preparedness, advertising in its social bearings; but only a very exceptional person would be entitled to opinions on all of even these few matters. And yet most of us have opinions on all these, and on many other questions of equal importance, of which we may know even less. We feel compelled, as self respecting persons, to take sides when they come up for discussion. We even surprise ourselves by our omniscience. Without taking thought we see in a flash that it is most righteous and expedient to discourage birth control by legislative enactment, or that one who decries intervention in Mexico is clearly wrong, or that big advertising is essential to big business and that big business is the pride of the land. As godlike beings why should we not rejoice in our omniscience? James Harvey Robinson, The Mind in the Making.
Notice that this paragraph hinges on the sentence beginning And yet most of us have opinions on all these.... This sentence suggests the pattern that your summarizing sentence should probably take. The central idea of the paragraph is that we do not ordinarly take pains in forming our convictions on important matters, but we nevertheless express our opinions as a matter of right and even take delight in our apparent omniscience. The main clause of your summarizing sentence will express the second part of the central idea, retaining the author's ironic approach.
We are godlike beings who delight in our ability to form and express convictions on birth control, on intervention in Mexico, or on the role of big business, without a moment's thought.
To preserve the author's qualification in the first part of the paragraph, however, you must precede the main clause with a subordinate clause.
Although the few pains we take to understand such things as the situation in Russia, the sources of our food supply, the origin of the Constitution, the revision of the tariff, the policy of the Holy Roman Apostolic Church, modern business organization, trade unions, birth control, socialism, the League of Nations, the excess-profits tax, preparedness, and advertising in its social bearings give us little reason to have confidence in our opinions on these matters, we are godlike beings who delight in our ability to form and express convictions on birth control, on intervention in Mexico or on the role of big business, without a moment's thought.
But this "summary" is almost half as long as the original. To reduce it further, replace the specific examples with general terms.
Although the few pains we take to understand such things as social, political, economic, religious, and medical issues give us little reason to have confidence in our convictions on these matters, we are godlike beings who delight in our ability to form and express such convictions without a moment's thought.
This summary, less than one-third the length of the original, would be acceptable for most purposes, but occasionally even a shorter summary is desirable.
Although we have little reason to trust our convictions on the important issues of life, we delight in forming and expressing such opinions without a moment's thought.
Clearly this last sentence does not express everything in Robinson's paragraph, where the concreteness and the vigor of the short sentences are perhaps even more striking than its central thought. But a summary is concerned only with the central thought, not necessarily with retaining the author's style, and the central thought is preserved even in the shortest statement above.