The Bridge: Cohesion and coherence

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These two terms are often confused and, on initial training courses, sometimes conflated but they are different and need different treatments both in terms of analysis and in the classroom.

Similarities and differences

Both cohesion and coherence refer to how texts, whether spoken or written, make sense through internal connections.
Both cohesion and coherence refer to both sense connections and language connections.

but
Cohesion describes the way linguistic and meaning connections are made within a text without reference to the knowledge the reader / hearer brings or the wider context in which the text is set.
Coherence refers to how sense is made of a text within cultural conventions and in terms of meanings which maybe internal to the text or may refer to the reader / hearer's knowledge of the world or the context in which the text is set.

Some examples will help make this clear, with any luck.

Example 1: Spoken text: Mary: Have you seen my gardening gloves?
John: Did you have them in the garage?
Example 2: Spoken text: Mary: Have you seen my gardening gloves?
John: The roses needed pruning
Example 3: Written text: Honey buzzards are birds of prey. Their diet, however, consists largely of wasps and hornets, the nests of which they excavate using their long claws.
Example 4: Written text: I hope you got my last email. Are you coming to the do on Saturday? Don't forget to dress up 60s style! Mary will be very disappointed if you can't.

Texts 1 and 3 are cohesive as well as coherent but texts 2 and 4 are coherent without being cohesive.
Can you explain? Click here when you have an answer.

Example 1: Spoken text: Mary: Have you seen by gardening gloves?
John: Did you have them in the garage?
In this text, we do not need to know anything about where Mary and John are, what their relationship is or what they are doing. The text hangs together by virtue of being both coherent (John's answer is obviously relevant to Mary's question) and cohesive.
It is cohesive because John says:
Did you have them ...
and the pronoun them refers back to the gardening gloves in Mary's question, linking the question and the response grammatically.
Even if you have no idea what gardening gloves are, you can still understand that they are the object of both Mary's question and John's response.
The two utterances are linked in both meaning and grammar so they are coherent and cohesive.
Example 2: Spoken text: Mary: Have you seen my gardening gloves?
John: The roses needed pruning
In this text, we have to do some inferencing concerning what is meant. With luck, we can work out that John's answer suggests that he has borrowed the gloves to protect his hands when pruning the roses.
There is, however, no linguistic link between Mary's question and John's response.
Understanding the text requires us to know that gardening gloves protect your hands and that roses are thorny plants. That is knowledge of the world that we do not have to bring to the first example.
Knowing those two facts makes the dialogue comprehensible and, therefore, coherent but there is no sense that they are cohesive.
Example 3: Written text: Honey buzzards are birds of prey. Their diet, however, consists largely of wasps and hornets, the nests of which they excavate using their long claws.
This is a formal written text and it is conventionally written. It is both cohesive and coherent.
Coherence is achieved by the sense connections. We are told that buzzards are birds of prey and that primes us for the information that follows concerning what they eat and how they get it.
Cohesion comes through the connections of
    buzzards and they (twice)
    buzzards and their
    wasps and hornets and the nests of which
It is quite possible that the writer has no idea who might be reading the text so is careful to set the scene with the first, topic sentence, making it coherent, and connect the clauses grammatically, making it cohesive.
Example 4: Written text: I hope you got my last email. Are you coming to the do on Saturday? Don't forget to dress up 60s style! Mary will be very disappointed if you can't.
This is also a written text but more informal and it is clear that writer and reader know each other. The writer also knows that she/he does not have to explain items that we, as outsiders, do not understand. We do not know
    who Mary is (or whether it is her do that is the subject)
    where the do is
    why the do is happening
    what sort of a do it is
    the relevance of dressing in 60's fashion
All of this is known to both the writer and the reader so the text is, for them, perfectly coherent.
There are, however, no internal cohesive grammatical links between the sentences except for the elision of the verb after can't. Even here, we do not have enough data to know whether this refers to dressing up or coming to the do.
In short, the text is coherent to the participants but not cohesive in any real sense.

Achieving cohesion

Cohesion is achieved in two main ways and this guide will cover only the main ones. For more detail, follow the links at the end.

Grammatical cohesion
1. using pronoun references:
      When he found it, the shop was closed for the weekend
      When my brother arrived, he went straight to the kitchen
      There's the 47 bus. That's the one we need!
      Have you got anything larger? This is too small.
2. using pro-forms for verbs:
  Is Mary here. I think so.
  It may rain but I hope not.
3. using conjunctions and conjuncts:
      It was raining so I stayed in
      She came because she wanted to meet his brother
      The costs are spiralling out of control. Nevertheless, the government will press ahead.
4. omitting an item that is understood (elision):
      The first problem is serious, the second even more so
      John came home, cooked a meal and went out
      The doctor said I should take more exercise and I will
Lexical cohesion
1. repeating an item:
  His son went to university with my son
2. using synonyms:
  Two lorries broke down but only one truck was towed away
3. using hypernyms (superordinates)
  Two lorries broke down but only one vehicle was towed away
4. using vague terms
  The paint pot leaked and the stuff was all over the bench

For more, see the guides linked below, especially if terms like hypernym are slightly mysterious to you.

To see if you can remember this, try a short test.

Achieving coherence

Coherence depends less on explicit linguistic connections and more on how texts are linked in terms of meaning and logical progression.
Coherence may be maintained, as we saw above by the writer / speaker and the hearer / reader sharing knowledge that it outside the text.

Shared information
1. Cultural knowledge:
  We needed a dignitary to do the deed and persuaded the Prince to open the new library
  There are many princes in the world but in this text, it is clear that both writer and reader / speaker and hearer know which prince is the reference, hence the capital letter on Prince. In this case there is only one prince in question.
2. Institutional knowledge:
  The head has said that the children must go to class in silence
  In this case, the parties to the text know that the head referred to is the head of a particular school.
3. Personal information:
  I'd like to help but you know my back won't bear it
  In this case, the fact that the writer / speaker has a bad back is known to both participants.
Topic signalling
1. Topic sentences:
  This essay concerns the use of recreational drugs. The most common of these is marijuana.
  Many well-written paragraphs will begin with a topic sentence which leads the reader to be able to predict the content of the paragraph. In fact, reading only the topic, often the first, sentence of every paragraph in a text is a good way quickly to get its gist.
2. Topicalising:
  That restaurant? No, you wouldn't like the food.
  English has few grammatically sound ways of topicalising but other languages routinely place the topic at the beginning of clauses whatever its grammatical function.
Staging
1. Conjunctions:
  Well, we have to buy the tickets and then we'll be able to jump the queue at the door.
  Conjunction allows the text producer to signal a wide range of internal connections including addition, concession and condition. These are sense relations so belong under the topic of coherence but they also figure above under cohesion because they represent internal grammatical connections, too.
  There are guides on this site to all aspects of conjunction.
2. Conjuncts:
  The first thing is to make sure the surface is free from grease. Secondly, gently score the surfaces. Finally, apply the glue.
  As the name implies, conjuncts usually refer to previous clauses, making the sense and grammatical connections clear.
3. Text staging:
      This happened to me in France.
      I was trying to hitchhike from Paris to Nice and ...
      In the end, it all worked out well but next time I'll take the train!
  Different text types will exhibit different information staging. Here, the example is a recount with a scene setting, a description of what happened and a coda expressing the writer / speaker's response to the events.
Lexical chaining
1. Tense forms are usually kept consistent so a text that begins in the present tense usually stays there and a narrative which uses past tenses will normally not stray into other tenses.
2. Certain lexical items will predictably form chains in texts so a text about health will general include a chain of illnesses and complaints along with a chain concerned with health professionals and yet another with a chain of treatments and cures.
  This phenomenon is to do with the field in which the text maker is operating (the register).

As you can see, cohesion and coherence, while being closely linked and showing some overlap are qualitatively different.
Trying to tackle both areas at the same time in a classroom is not a recipe for unalloyed success.

Try a final matching task.

If that's all clear enough to you, you can go on to the guides below (on the right). If you still feel slightly confused, try the links on the left.

Guides in other areas
Initial plus essential guides	In-service guides
cohesion essentials	cohesion
conjunction essentials	pro-forms
personal pronouns	substitution and ellipsis
lexical relationships	theme and rheme