Coherence

Coherence is sometimes called cohesion, even though some would claim that the two terms denote phenomena that are obviously related, but clearly different. We use coherence to cover both the extent to which a text hangs together, as it were, and the various linguistic and structural means of achieving this coherence.

In a coherent text, there are logical links between the words, sentences, and paragraphs of the text. The term comes from the Latin verb co-haerere, which means 'to stick together' (OED). Another way to describe coherence is to say that it has to do with good and smooth text flow. A writer must maximise understanding of a text by making it as clear and logical as possible.

Coherence can be achieved in a number of ways. Oshima & Hogue (2006) suggest the following four:

  • Repeating key nouns
  • Using consistent pronouns
  • Using transition signals to link ideas
  • Arranging your ideas in logical order

Starting with the last point, for the reason that it is a paramount aspect, any academic text will be incomprehensible unless the ideas expressed in it are arranged in some sort of logical fashion.

There are several different kinds of logical order, but some of the more frequently used are chronology, importance, and contrast. Chronology, firstly, has to do with time, and in terms of logic, events are ordered in a sequence. Secondly, importance means that ideas are discussed in a sequence which implies either a increasing or decreasing order of importance. Thirdly, contrast has to do with ordering ideas by contrasting or comparing them.

The last but one point - transition signals (sometimes called linking words or linking adverbials) - has to do with the use of specific words and phrases that evoke links and transition between ideas.

As was emphasised above, there is no substitute for ordering the various ideas and parts of a text in a logical way. However, even when this is done in a satisfactory manner, there is often a need to strengthen the organisational pattern of a text passage by inserting logical markers.

There is a multitude of words and phrases like these, and they can be grouped in different classes based on the function they serve. The link below will take you to a list of different transitional and linking words.

A list of linking words for different purposes (Björk & Räisänen 1997) (click to expand/contract)

Purpose/function

 

Connective words (linking words)

addition

and, also, moreover, in addition, furthermore, besides

contrast

but, however, in contrast, on the one hand - on the other hand,
the former - the latter, actually, nevertheless, while

similarity

such, similarly, the same, equally

exemplification

for example, for instance, in other words

chronology

first, second, then, afterwards, thereafter, meanwhile, at the
same time, next, later, finally, at last, ultimately

causality

so, consequently, therefore, thus, accordingly, although,
because of, hence, as a result, since

attitude

of course, naturally, obviously, fortunately, unfortunately,
certainly, admittedly

summary

to summarise, to sum up, in conclusion, in brief

                           
                         Björk & Räisänen (1997, p.186-187)


The point called using consistent pronouns has to do with substituting nouns with pronouns in an effective way. A text that does not use pronouns to some extent will come across as overly repetitive. The important part when using pronouns is to be consistent by using the same person and number throughout the paragraph or text. Click on the link below to see a comparison between a text with and without pronouns.

Example: The effect of presence and absence of pronouns in a text (click to expand/contract)

Absence of suitable pronouns

The director said that the director was in a hurry. The director was late for picking the director's sister up at the airport, but the director did not know where the airport was. 

Presence of suitable pronouns

The director said that he was in a hurry. He was late for picking his sister up at the airport, but he did not know where it was.


The fourth way to achieve coherence in a text passage is to repeat key nouns. However, even if nouns typically are the words that should be repeated, also words from other word classes can be repeated if they are central to the topic of the text. There is no set rule as to how often a key noun can be repeated - the guiding principle must be clarity and an avoidance of making the reader feel that there is too much repetition.

An alternative to repeating a key noun over and over is to use another noun that has the same, or at least very similar, meaning: a synonym.

Click on the link below to see an example of effective repetition of key nouns.

Example: The repetition of key nouns in a text (Oshima & Hogue 2006) (click to expand/contract)

Gold, a precious metal, is prized for two important characteristics. First of all, gold has a lustrous beauty that is resistant to corrosion. Therefore, it is suitable for jewelry, coins and ornamental purposes. Gold never needs to be polished and will remain beautiful forever. For example, a Macedonian coin remains as untarnished today as the day it was made 25 centuries ago. Another important characteristic of gold is its usefulness to industry and science. For many years, it has been used in hundreds of industrial applications, such as photography and dentistry. The most recent use of gold is in astronauts' suits. Astronauts wear gold-plated heat shields for protection when they go outside spaceships in space. In conclusion, gold is treasured not only for its beauty but also for its utility.

 

Oshima & Hogue (2006, p. 22)


For further reading: Connecting events in a text (Hamp Lyons & Heasley 2006) (click to expand/contract)

Hamp Lyons & Heasley (2006) suggest seven ways in which writers can link sentences together to form texts. To some extent, these overlap with the four strategies proposed by Oshima & Hogue (2006) above in this subsection.

1. Repeating a word or words from the first sentence in the second sentence.

Energy in food is measured in calories. Approximately 50% of the calories we consume are used in physical activity.

2. Use a synonym (word with the same meaning) of a word from the first sentence in the second.

The surroundings in which we carry out our daily lives are very important to us. We are continually aware of our environment as we go about our business.

3. Use a pro-form (e.g. pronoun) in the second sentence.

Trees are an essential part of a city's development. They help reduce pollution and provide shade.

4. Use a sequence marker [e.g. Firstly, secondly/ a), b), c)]

The maize plant faces two main pests. The first is the weevil borer whose larvae eat their way through the maize plant.

5. Repeat a sentence structure

We need to make our buildings more energy efficient. We need to make our cars less polluting.

6. Use connectives (e.g. addition, time relaters)

The UAE is spending a lot of money to improve its environment. For example, it invested millions of dollars developing forests in the desert.

7. Use a hyponym (e.g. police station -> building |  car -> means of transport)

We are losing rain forests at a great rate. Millions of trees are being cut down every week.

 

Hamp Lyons & Heasley (2006, p. 80)