Main and Secondary Ideas of a Text – What they are and examples


We explain what the main and secondary ideas of a text are, the characteristics of each one and how to identify them.

main and secondary ideas
Main and secondary ideas are distinguished by their importance in the text.

What are the main and supporting ideas of a text?

Every text has different kinds of ideas that, despite addressing the same topic, differ in their hierarchy within the text, that is, in their degree of centrality or importance when reflecting the author’s point of view. That is to say: every text has essential ideas and complementary ideas.

Thus, one can speak of main ideas, which are those of the highest rank and which contain the core, nuclear or key information, and are indispensable for the text; and also of secondary ideas, of lesser rank and that are detached from the main ones, occupying a complementary and more or less optional place within the text. Each of them is characterized as follows:

Main ideas:

  • Express key information of the development of the theme, so they constitute the backbone of the text.
  • They tend to be less in quantity than the secondary ones, but more central.
  • Are indispensable, they cannot be deleted without making the text something that says nothing.
  • They are autonomous, so they can be read separately. If anything, they depend on other main ideas for your context.
  • May not be explicit, but must be deduced from reading the text.
  • There are generally one or two articulating each paragraph.

Secondary ideas:

  • Amplify, modulate, exemplify or characterize the information provided by the main ideas.
  • They are usually more abundant than the main ones, but at the same time optional.
  • You can do without them and still get a general idea of ​​the text.
  • They depend directly on the main ideasWithout them they cannot be understood.
  • They can be as many as you want.

How to identify the main and secondary ideas?

Identifying main and supporting ideas can be more or less difficult, depending on the complexity of the text. Of course, it will always be absolutely essential to read it carefully to recognize your ideas. Once the global reading is complete, we can reread each paragraph as necessary, paying attention to the following:

  • To determine the main ideas. The first thing we have to think about to find the main ideas is what is the text about? Well, answering that question in our own words, preparing a small personal summary, will reveal what information we have left from the reading. This is important because the main ideas are not always made explicit in the text, but are formed as we read it. We can even make a small outline of the ideas that constitute the conceptual skeleton of the text, those that constitute the central information of the text and that are found in each paragraph. What would be those key ideas that each paragraph summarizes? Which, as a whole, are the ones that then summarize the full text?
  • To determine secondary ideas. This is always much simpler, since when differentiating the main ones, the discard itself indicates that the rest will necessarily be secondary ideas. Even so, we can look at the ideas that surround each of these main ideas, and that follow from it. What are the most relevant of these secondary ideas? What main ideas do they emerge from, to be incorporated into our scheme of the previous item?

Example of main and secondary ideas

Below we present an example of the extraction of main and secondary ideas, from a fragment of the essay “De la Amistad” by the French writer Michel de Montaigne (1533-1592):

«The relationship between parents and children is based on respect. It is communication that fuels friendship, and this cannot occur between children and parents due to the disparity that exists between them, and also, because it would conflict with the duties that nature imposes: not even parents can tell their children all their intimate thoughts, so as not to give rise to a damaging and damaging trust, neither the children could direct to the parents the warnings and corrections that constitute one of the first duties of friendship.

From this long paragraph of the essay, we must extract the main idea (s). After reading it completely, we can say that the fundamental idea of ​​the fragment is the following:

“It is communication that fuels friendship, and this cannot occur between children and parents due to the disparity that exists between them, and also, because it would clash with the duties imposed by nature”

If we look, other secondary ideas emerge from this parent idea that come immediately, such as:

  • “Nor can parents tell their children all their intimate thoughts, so as not to give rise to a damaging and damaging trust”
  • “Nor could children direct the warnings and corrections to their parents that constitute one of the first duties of friendship.”

These two ideas complement the main one, explain it more extensively and they give us a reason for it. None of these secondary ideas makes sense without the main idea that structures them and provides them with a framework of meaning, that is, a direction and a context.

The underlining of main and secondary ideas

The underline it is a technique widely used to mark main and secondary ideas in a text, which allows us to return to the reading later and know where the most relevant information is located.

The usual method of underlining is to mark the main ideas, either by underlining them with a pencil or by highlighting them with some color, to distinguish them from the rest of the text. It is also possible to frame the sentence in brackets or other signs of our preference.

A variant of the same technique is the one that assigns a color to the main ideas and a different color to the secondary ones, with the condition that there are no more colors in the text, since the idea is to classify and organize the sentences, and not to turn the text into a carnival. This option can be ideal, especially if we are learning to distinguish the main ideas from the secondary ones.