Headings and Subheadings and Why One is the Wrongliest Number

Lone subheadings are one of the most frequently occurring mistakes that I encounter in my work as a computer-book acquisitions and development editor. I use the term lone subheading in connection with a section having only one subsection, a topic with but one subtopic.

Meeting the Enemy

Example 1 illustrates the problem. It shows a poorly-structured book section on "Government" having only one subtopic: "Dictatorships".

Example 1. The problem of a single subhead

A-head: Government

Our nation is a democracy. We have a president, a house, and a senate. Every four years we have an election—elections are similar to carnivals—in which we vote someone into office as president. Likewise, we vote in senators and representatives. During the ensuing four years, all these people spend as many of our tax dollars as possible.

B-head: Dictatorships

Dictatorships are alternative forms of government wherein one person is "the boss". There are no elections per se. When citizens tire of a dictator, they often shoot him. Usually the dictator will shoot back, making transitions very messy affairs.

The proper way to think about a heading is that it splits its topic. You can't split something into one piece. Anyone who's ever split firewood or cut a slice of pie knows that. When you split something, you by definition end up with at least two pieces.

Finding the Hidden Subtopic

The author in Example 1 began his discussion of government by talking about democracy. Then the author switched to dictatorships, marking the change with a subheading. At that point, the author should have stopped and thought to himself:

  1. "I'm splitting my topic."
  2. "What are the two pieces?"
  3. "One is dictatorships, and the other is..."
  4. "Democracies!"

It's obvious now, isn't it? The overall topic is government, and we are discussing democracies and dictatorships. Each deserves its own subheading, as in Example 2.

Example 2. A main topic correctly split into two subtopics

A-head: Government

There are many forms of government in the world. We happen to live in a democracy, but others live under dictatorships.

B-head: Democracies

Our nation is a democracy. We have a president, a house, and a senate. Every four years we have an election—elections are similar to carnivals—in which we vote someone into office as president. Likewise, we vote in senators and representatives. During the ensuing four years, all these people spend as many of our tax dollars as possible.

B-head: Dictatorships

Dictatorships are alternative forms of government wherein one person is "the boss". There are no elections per se. When citizens tire of a dictator, they often shoot him. Usually the dictator will shoot back, making transitions very messy affairs.

"Democracies" in Example 1 is what I refer to as a hidden subtopic, hidden because it is not identified with a subheading like the other subtopic. Example 2 identifies this subtopic, exemplifying the rule that you always split a topic into at least two pieces. If you do not have two pieces, then you do not need any subheading. If you do have two pieces, then each deserves a subheading.

Example 2 illustrates another rule of good writing: always introduce your topic. Having split the topic of government into subtopics based upon forms of government, it's neccessary to go back and write an introduction to the overall topic. Never follow a main heading immediately with a subheading. Always write an introduction to your main section first. Then begin your sequence of subsections.

Example 2 also shows what  I think of as the canonical format for a section that you divide into subsections: Write your main heading. Say something brief about the topic to introduce it. Then put all detailed discussion under the subheadings. Whenever I break a topic into subtopics, I keep the text under the main heading short. I want my main text to introduce the topic as a whole, but it's an introduction. Detailed discussion goes into the subsections.

Excising the False Subtopic

Just as there sometimes can be hidden subtopic, there can also be a false subtopic. Say an author wishes to talk only about democracies, as in Example 3. Democracy is a type of government. The author writes an introduction to the topic of government, and then launches into the only form of government he wants to discuss in his text.

Example 3. A false subtopic

A-head: Government

There are many forms of government in the world. We happen to live in a democracy.

B-head: Democracies

Our nation is a democracy. We have a president, a house, and a senate. Every four years we have an election—elections are similar to carnivals—in which we vote someone into office as president. Likewise, we vote in senators and representatives. During the ensuing four years, all these people spend as many of our tax dollars as possible.

While it's true that "Democracies" is a subtopic of "Government", I'd argue that now we really have only one topic: democracies, and the resulting organization should be as in Example 4.

Example 4. The corrected, single topic

A-head: Democracies

There are many forms of government in the world. We happen to live in a democracy. We have a president, a house, and a senate. Every four years we have an election—elections are similar to carnivals—in which we vote someone into office as president. Likewise, we vote in senators and representatives. During the ensuing four years, all these people spend as many of our tax dollars as possible.

 Hidden subtopics and false subtopics are two sides of the same coin. The solution to Example 1 was in recognizing the hidden subtopic. The solution to Example 3 is in realizing that there really is only one topic under discussion.

Revisiting the Hidden Subtopic

Very often I'm confronted the situation in Example 5. There is no lone subheading. The section appears on the surface to be properly divided into mulitple subtopics. Yet one subtopic hasn't been explicitly called out.

Example 5. An easily-overlooked, hidden subtopic

A-head: Government

Our nation is a democracy. We have a president, a house, and a senate. Every four years we have an election—elections are similar to carnivals—in which we vote someone into office as president. Likewise, we vote in senators and representatives. During the ensuing four years, all these people spend as many of our tax dollars as possible.

B-head: Dictatorships

Dictatorships are alternative forms of government wherein one person is "the boss". There are no elections per se. When citizens tire of a dictator, they often shoot him. Usually the dictator will shoot back, making transitions very messy affairs.

B-head: Kingships

 A few countries around the world are nominally ruled by kings (or queens). In most cases, real power in these countries is vested in an elected parliament, and the king or queen acts a figurehead, a personification, if you will, of the state. Because the titular ruler personifies the state, they can be most useful when a human representative of the state is required.

Example 5 represents the exact same problem as Example 1, but the hidden subtopic problem is better disguised as a result of their being two subheadings rather than one. The passage "looks" good on the surface, but the content on democracy really belongs in its own subsection, as in Example 6.

Example 6. The now-unhidden subtopic

A-head: Government

Government is the manner in which people regulate themselves so as to live together in harmony.

B-head: Democracies

Our nation is a democracy. We have a president, a house, and a senate. Every four years we have an election—elections are similar to carnivals—in which we vote someone into office as president. Likewise, we vote in senators and representatives. During the ensuing four years, all these people spend as many of our tax dollars as possible.

B-head: Dictatorships

Dictatorships are alternative forms of government wherein one person is "the boss". There are no elections per se. When citizens tire of a dictator, they often shoot him. Usually the dictator will shoot back, making transitions very messy affairs.

B-head: Kingships

A few countries around the world are nominally ruled by kings (or queens). In most cases, real power in these countries is vested in an elected parliament, and the king or queen acts a figurehead, a personification, if you will, of the state. Because the titular ruler personifies the state, they can be most useful when a human representative of the state is required.

Cementing Your Mental Model

How you think about elements such as sections and subsections that make up a book has a lot to do with the quality of written content that you produce. Writing with the correct mental model in mind is important. One key to writing effective subheadings is to remember that:

  • Subheadings split a topic

The rule that you must have more than one subsection flows directly from this key point. Your ability to recognize hidden and false subtopics also falls in part from this point. Rules about headings and subheadings that seem arbitrary and confusing at first almost cease to feel like "rules" at all when you write with the correct mental model in place.

Note: For a take on mental models in general, and their importance, read my article, On the Importance of Mental Models.