Unity @ the Paragraph Level

Readers can generally follow the logic of a discussion better when a paragraph is unified by a single purpose. Paragraphs that lack a central idea and that wander from subject to subject are apt to confuse readers, making them wonder what they should pay attention to and why.


Paragraphs need to stay focused on one topic. A good way to make sure you are staying focused is to have a solid topic sentence—a sentence that explains what the paragraph will discuss—and be sure to add only those details or examples that relate directly to that topic.

The film industry releases more sequels than original movies these days. From the Marvel comic book adaptations to the seventh installment of the latest horror series, Hollywood seems determined to run a franchise into the ground rather than take a chance on something new. Instead of meeting new characters, moviegoers learned more about Captain America in The Winter Soldier, and they followed the ongoing story of Thor and Loki in Thor: The Dark World. Even the horror industry seems to be losing creativity—apparently the four Paranormal Activity movies need yet another sequel. Remember the hype around the Star Wars prequels a few years ago? Science fiction movies often have prequels that fans love to see. Moviegoers are ready for something new in theatres; hopefully, the producers in Hollywood will realize that the age of the sequel is coming to an end.

In this paragraph, the sentences are related to one common idea: movie sequels. The first few sentences focus on this idea but the two sentences about Star Wars and science fiction prequels do not fit the main idea of the paragraph. Although they contain interesting information, these sentences disrupt the paragraph’s unity. The writer should move them to another point in a new paragraph (about prequels or maybe science fiction movies, depending on the focus of the paper) or even get rid of them entirely.

Another thing to keep in mind when considering paragraph unity is sentence order. Sometimes, you just need to reorder your sentences to make everything unified. Try moving sentences around after you decide whether you are using deductive or inductive reasoning to structure your paragraph. If you are using deductive, then begin with a general statement and move into supporting details. If you are using inductive, begin with a specific detail and then move out to the general statement from there. Then, make sure that all of your sentences relate to the overall point you are making in that paragraph.

To Measure Unity, Number Sentences by Level of Abstraction

To ensure that each paragraph is unified by a single idea, Francis Christensen, in Notes Toward a New Rhetoric (NY: Harper & Row, 1967), has suggested that we number sentences according to their level of generality.

According to Christensen, we would assign a 1 to the most general sentence and then a 2 to the second most general sentence, and so on. Christensen considers the following paragraph, which he excerpted from Jacob Bronowski’s The Common Sense of Science, to be an example of a subordinate pattern because the sentences become increasingly more specific as the reader progresses through the paragraph:

  1. The process of learning is essential to our lives.
    • All higher animals seek it deliberately.
      • They are inquisitive and they experiment.
        • An experiment is a sort of harmless trial run of some action which we shall have to make in the real world; and this, whether it is made in the laboratory by scientists or by fox-cubs outside their earth.
          • The scientist experiments and the cub plays; both are learning to correct their errors of judgment in a setting in which errors are not fatal.
            • Perhaps this is what gives them both their air of happiness and freedom in these activities.

Christensen is quick to point out that not all paragraphs have a subordinate structure. The following one, which he took from Bergen Evans’s Comfortable Words, is an example of what Christensen considers a coordinate sequence:

  1. He [the native speaker] may, of course, speak a form of English that marks him as coming from a rural or an unread group.
  2. But if he doesn’t mind being so marked, there’s no reason why he should change.
  3. Samuel Johnson kept a Staffordshire burr in his speech all his life.
  4. In Burns’ mouth the despised lowland Scots dialect served just as well as the “correct” English spoken by ten million of his southern contemporaries.
  5. Lincoln’s vocabulary and his way of pronouncing certain words were sneered at by many better educated people at the time, but he seemed to be able to use the English language as effectively as his critics.