coherent definition essay

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Coherence in Writing

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Have you ever read a piece of writing and wondered what point the writer was trying to make? If so, that piece of writing probably lacked coherence. Coherence is an important aspect of good writing—as important as good grammar or spelling. However, it is also rather harder to learn how to do it, because it is not a matter of simple rules.

Coherent writing moves smoothly between ideas. It guides the reader through an argument or series of points using signposts and connectors. It generally has a clear structure and consistent tone, with little or no repetition. Coherent writing feels planned —usually because it is. This page provides some tips to help you to develop your ability to write coherently.

Defining Coherence

Dictionary definition of coherence

cohere , v. to stick together, to be consistent, to fit together in a consistent, orderly whole.

coherence , a sticking together, consistency.

Source: Chambers English Dictionary, 1989 edition.

The dictionary definition of coherence is clear enough—but what does that mean in practical terms for writers?

Once you have achieved coherence in your writing, you will find that:

Your sentences and ideas are connected and flow together;

Readers can move easily through the text from one sentence, paragraph or idea to the next; and

Readers will be able to follow the ideas and main points of the text.

On the other hand, a text that is NOT coherent jumps between ideas without making clear connections between them. It is often hard to follow the argument. Readers may find themselves unclear about the point of particular paragraphs or even whole sections. There may be odd sentences that do not fit well with the previous or following sentence, or paragraphs that repeat earlier ideas.

All these issues provide pointers for how to develop coherence.

Elements of Coherence

There are several different elements that contribute to coherence, or are closely linked to the concept.

They include:

Cohesion , or whether ideas are linked within and between sentences.

Unity , or the extent to which a sentence, paragraph or section focuses on a single idea or group or ideas. In any given paragraph, every sentence should be relevant to a single focus.

A joint effort

Together, cohesion and unity mean that sentences and paragraphs are connected around a central theme.

• Flow , or how the reader is led through the text. Some of this is about the ordering of ideas, but it also takes into account issues like phrasing, rhythm and style. Some people define flow as the quality that makes writing engaging and easy to read.

Levels of Coherence

We can consider coherence at several different levels. These include:

Within sentences. A sentence is coherent when it flows naturally, and uses correct grammar , spelling and punctuation . Coherence also includes the use of the most appropriate words, and avoidance of redundancy.

Between sentences . Coherence between sentences means that each sentence flows logically and naturally from the previous one. Connections are made between them so that readers can see the flow of ideas, and how each sentence is linked to the previous one.

Within paragraphs . This is a logical extension of coherence between sentences. Coherence within a paragraph means that the sentences within the paragraph work together as a whole to present a complete thesis or idea.

Why single-sentence paragraphs don’t work

This definition of ‘within paragraph’ coherence explains why you should (almost) never use single-sentence paragraphs. A single sentence is (almost) never going to be able to provide a complete summary of your thesis or idea.

Between paragraphs . For most pieces of writing, you will also need to consider how the paragraphs fit together. Each paragraph covers an idea or thesis—and must then be connected logically to the next paragraph, so that your overall thesis is built step-by-step.

Between subsections or sections . This final level of coherence is only really important for longer documents. You must create a logical flow between different sections, to guide your reader from one to the next so that they can follow the development of your ideas.

Techniques to Improve Coherence

The first step to improving coherence is to plan your writing in advance.

Decide on the main point that you want to make, and the ideas that will lead your reader towards your point. It is also helpful to consider your planned audience, and what they want from your text.

There is  more about this in our page on Know Your Audience . You may also find it helpful to read our page on Know Your Medium , to check whether there is anything about your publishing medium that you need to consider ahead of starting to write.

There are some techniques that you can use to help improve coherence within your writing. These include:

Using transitional expressions and phrases to signal connections

Words and phrases like ‘however’, ‘because’, ‘therefore’, ‘additionally’, and ‘on the one hand... on the other’ can be used to signal connections between sentences and paragraphs.

WARNING! Real connections needed!

Transitional phrases and words should only be used where the ideas really are connected.

Just inserting transitional expressions will not connect your ideas. Instead, you need to create a reasonable progression of ideas through a paragraph or section.

You also need to use transitional expressions sparingly. Not all ideas need an obvious link—and sometimes putting one in can seem awkward and contrived.

Using repeating forms or parallel structures to emphasise links between ideas

Generally speaking, repetition of words and phrases is unadvisable.

However, used sparingly, you may be able to harness repetition as a way to signal connections between sentences or ideas.

For example, many research papers have a section setting out the limitations of the study. These limitations can often be quite diverse, which makes for a rather disjointed section. To overcome this issue, writers often use the form ‘First... Second... Finally...’ to demonstrate the links between the disparate ideas.

Using pronouns and synonyms to eliminate unnecessary repetition

Repetition is often the enemy of coherence because it interrupts your movement through the writing. You tend to get distracted by the repeated words, and lose the thread of the argument or idea.

Pronouns and synonyms are a good way to avoid repeating words and phrases. However, care is needed when using them, to avoid ambiguity. It is advisable NOT to use pronouns following a sentence with two elements that might take the same pronoun.

For example:

John was sure that Tom was wrong. He had made the same argument last week.

Who made the same argument last week? John or Tom?

It is better to use at least one name again than create ambiguity.

TOP TIP! Come back later

It is often hard to detect ambiguity in your own writing because you know what you wanted to say.

It is therefore a good idea to leave any piece of writing overnight, and read it again in the morning. This will often identify problems such as ambiguous pronouns, and give you a chance to revise them.

Revisit, Revise and Review

Alongside planning, the single most important thing that you can do to improve the coherence of a piece of writing is to review and revise it with the reader’s needs in mind.

When you have finished a piece of writing, put it aside for a while. Overnight is ideal, but longer is fine. Once you have had a chance to forget precisely what you meant, read it over again as if you were coming to it for the first time.

As you start to read, consider the focus of your text: the main point that you want to make.

With that in mind, consciously examine whether the ideas flow clearly through your sentences, paragraphs and sections. Can the reader grasp your argument and follow it through the text? Is there an obvious conclusion?

While you are reading, you should also consider whether there are any very long sentences. If so, shorten them, using transitional words or phrases to link them together effectively. This will make your writing easier to read, and it will naturally flow better.

A Final Thought

It is not always easy to know how to create more coherent writing.

The best way to do so is to plan your writing, and then review it carefully. You should particularly consider your focus, and your readers’ needs. In doing so, you may find it helpful to use some of the techniques described on this page—but they will not, in themselves, be sufficient without the planning and review.

Continue to: Writing Concisely Using Plain English

See also: The Importance of Structure in Writing Editing and Proofreading Copywriting

Definition of Coherence

Types of coherence, examples of coherence in literature, example #1:  one man’s meat (by e.b. white).

“Scientific agriculture, however sound in principle, often seems strangely unrelated to, and unaware of, the vital, grueling job of making a living by farming. Farmers sense this quality in it as they study their bulletins, just as a poor man senses in a rich man an incomprehension of his own problems. The farmer of today knows, for example, that manure loses some of its value when exposed to the weather … But he knows also that to make hay he needs settled weather – better weather than you usually get in June.”

This is a global level coherent text passage in which White has wonderfully unified the sentences to make it a whole. He has started the passage with a general topic, scientific agriculture, but moved it to a specific text about farmers and their roles.

Example #2:  A Tale of Two Cities (by Charles Dickens)

“The wine was red wine, and had stained the ground of the narrow street in the suburb of Saint Antoine, in Paris, where it was spilled. It had stained many hands, too, and many faces, and many naked feet, and many wooden shoes. The hands of the man who sawed the wood, left red marks on the billets; and the forehead of the woman who nursed her baby, was stained with the stain of the old rag she wound about her head again. Those who had been greedy with the staves of the cask … scrawled upon a wall with his finger dipped in muddy wine-lees—BLOOD.”

Example #3:  Animal Farm (by George Orwell)

“ Now , comrades, what is the nature of this life of ours? Let us face it: our lives are miserable, laborious, and short. We are born, we are given just so much food as will keep the breath in our bodies, and those of us who are capable of it are forced to work to the last atom of our strength … “No animal in England knows the meaning of happiness or leisure after he is a year old. The life of an animal is misery and slavery: that is the plain truth.”

Through the speech of the Old Major, Orwell starts the passage about the miserable nature of the life of animals on the animal farm , and then he inspires them to think about how to safeguard their interests on the farm. The entire paragraph is an example of coherent speech.

Example #4:  Unpopular Essays (by Bertrand Russell)

“The word “philosophy” is one of which the meaning is by no means fixed. Like the word “religion,” it has one sense when used to describe certain features of historical cultures, and another when used to denote a study or an attitude of mind which is considered desirable in the present day. Philosophy, as pursued in the universities of the Western democratic world, is, at least in intention, part of the pursuit of knowledge, aiming at the same kind of detachment as is sought in science …”

Coherence links the sentences of a work with one another. This may be done with paragraphs, making sure that each statement logically connects with the one preceding it, making the text easier for the readers to understand and follow. Also, ordering thoughts in a sequence helps the reader to move from one point to the next smoothly. As all of the sentences relate back to the topic, the thoughts and ideas flow smoothly.

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When and How to Write Coherently

• Definition & Examples
• When & How to Write Coherently

The Importance of Coherence

Say you’re reading a piece of academic writing – maybe a textbook. As you read, you find yourself drifting off, having to read the same sentence over and over before you understand it. Maybe, after a while, you get frustrated and give up on the chapter. What happened?

Nine times out of ten, this is a symptom of incoherence. Your brain is unable to find a unified argument or narrative in the book. This may become frustrating and often happens when a book is above your current level of understanding. To someone else, the writing might seem perfectly coherent, because they understand the concepts involved. But from your perspective, the chapter seems incoherent. And as a result, you don’t get as much out of it as you otherwise would.

How can you avoid this in your own writing? How can you make sure that readers don’t misunderstand you (or just give up altogether)? The answer is to work on coherent writing. Coherence is perhaps the most important feature of argumentative writing. Without it, everything falls apart. If an argument is not coherent, it doesn’t matter how good the evidence is, or how beautiful the writing is: an incoherent argument will never persuade anyone or even hold their attention.

How to Create Coherence

• Keep your reader in mind . Coherence is a matter of perception, so you have to write in a way that your reader will understand. Make sure you use terms that the reader will understand. Also, use lines of reasoning that the reader can follow. In school assignments, the reader is your teacher or professor, so this is the person you need to keep in mind as you write.
• Repeat key terms . Many writers are afraid to repeat words because they don’t want their writing to become “monotonous.” That’s a good instinct, but actually it’s helpful to repeat words – as long as they’re the right words! Look again at the example in §2: it uses the term “credit card” in nearly every sentence. But it’s OK, because “credit card” is a key term. You should use key terms frequently, but use variety in non-key terms.
• Define your terms . In complex arguments, it may be necessary to define a term for your reader. This is especially important when you’re using a word that has multiple meanings for different people (such as “democracy,” “morality,” “utilitarianism,” or “God”).
• Craft smooth transitions . Make sure that each paragraph flows naturally into the next one. If you shift topics abruptly, your readers will probably find your writing incoherent.
• Check for self-contradictions . Once you’ve made a statement, you have to stick to it! Take care that your later sentences don’t contradict or undermine what you’ve said before.

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Coherence in Composition

Guiding the Reader to Understand a Piece of Writing or Speech

• An Introduction to Punctuation
• Ph.D., Rhetoric and English, University of Georgia
• M.A., Modern English and American Literature, University of Leicester
• B.A., English, State University of New York

In composition , coherence refers to the meaningful connections that readers or listeners perceive in a written or oral text , often called linguistic or discourse coherence, and can occur on either the local or global level, depending on the audience and writer.

Coherence is directly increased by the amount of guidance a writer provides to the reader, either through context clues or through direct use of transitional phrases to direct the reader through an argument or narrative.

Word choice and sentence and paragraph structure influence the coherence of a written or spoken piece, but cultural knowledge, or understanding of the processes and natural orders on the local and global levels, can also serve as cohesive elements of writing. 

Guiding the Reader

It is important in composition to maintain the coherence of a piece by leading the reader or listener through the narrative or process by providing cohesive elements to the form. In "Marking Discourse Coherence," Uta Lenk states that the reader or listener's understanding of coherence "is influenced by the degree and kind of guidance given by the speaker: the more guidance is given, the easier it is for the hearer to establish the coherence according to the speaker's intentions."

Transitional words and phrases  like "therefore," "as a result," "because" and the like serve to move connect one posit to the next, either through cause and effect or correlation of data, while other transitional elements like combining and connecting sentences or repetition of keywords and structures can similarly guide the reader to make connections in tandem with their cultural knowledge of the topic.

Thomas S. Kane describes this cohesive element as "flow" in "The New Oxford Guide to Writing," wherein these "invisible links which bind the sentences of a paragraph can be established in two basic ways." The first, he says, is to establish a plan in the first of the paragraph and introduce each new idea with a word marking its place in this plan while the second concentrates on the successive linking of sentences to develop the plan through connecting each sentence to the one before it.

Constructing Coherence Relations

Coherence in composition and constructionist theory relies on a readers' local and global understanding of the written and spoken language, inferring the binding elements of text that help guide them through understanding the author's intentions. 

As Arthur C. Graesser, Peter Wiemer-Hasting and Katka Wiener-Hastings put it in "constructing Inferences and Relations During Text Comprehension," local coherence "is achieved if the reader can connect the incoming sentence to information in the previous sentence or to the content in working memory." On the other hand, global coherence comes from the major message or point of the structure of the sentence or from an earlier statement in the text. 

If not driven by these global or local understanding, the sentence is typically given coherence by explicit features like anaphoric references, connectives, predicates, signaling devices and transitional phrases. 

In any case, coherence is a mental process and the Coherence Principle accounts for "the fact that we do not communicate by verbal means only," according to Edda Weigand's "Language as Dialogue: From Rules to Principles." Ultimately, then, it comes down to the listener or leader's own comprehension skills, their interaction with the text, that influences the true coherence of a piece of writing.

• What Is Cohesion in Composition?
• Unity in Composition
• Learn About Précis Through Definition and Examples
• Definition and Examples of Transitional Paragraphs
• What Is an Echo Word?
• Definition Examples of Collage Essays
• Editing and Proofreading Marks in Composition
• Focusing in Composition
• The Four Master Tropes in Rhetoric
• English Phrasal Verbs: Definition
• Cue Word (or Phrase) in English
• Substitution in English Grammar
• Definition and Examples of Text Linguistics
• Paragraph Transition: Definition and Examples
• The Definition of a Review in Composition
• Definition and Examples of Body Paragraphs in Composition

Module 8: Revising a Research Paper

Writing coherently, learning objectives.

• Define coherence in terms of writing
• Identify strategies to revise your argument for coherence

The term “coherence” comes from the verb “to cohere,” which means “to be united,” “to form a whole,” or “to be logically consistent”.

Coherence in writing refers to the big picture of a text. How can you construct an essay or research paper to create a united, logically consistent whole?

The USDA’s controversial and now deprecated food pyramid.

Consider this example:

Micronutrients play a vital role in the maintenance of healthy skin and immune function.  Of course, nothing is better for healthy skin than sleep and proper hydration. Many Americans drink too little water every day. There has been a good deal of debate about the 8-glasses-of-water advice that many of us remember from growing up. Will this advice go the way of the food pyramid? As it turns out, the food pyramid does not represent a medically ideal diet. A number of health organizations have criticized the food pyramid’s advice, and some have even suggested that the food industry had far too great a role in its creation. It certainly wouldn’t be the first time the food industry has intervened in public health policy.

This passage is cohesive, meaning that one sentence flows from the next. But it’s not coherent. Why?

• The topics of the individual sentences vary widely. We go from hearing about micronutrients to sleep and hydration to recommended water intake to the food pyramid. If sentences (and paragraphs) in a piece of writing don’t share common topics and ideas, how is the reader supposed to understand what the piece is about?
• The paragraph lacks a topic sentence signaling its main idea or purpose. The first sentence sounds like it could be a topic sentence, but the paragraph doesn’t stay with micronutrients for long.

Overall, this paragraph illustrates the pitfalls of associative organization (healthy skin → water → nutrition advice→ food pyramid) and topic sentences that fail to live up to the promise they make to readers. Your reader will become disoriented, fail to see your point (if you have one), and walk away frustrated.

Revising for Coherence

A coherent text needs a strong, logical structure. To revise for coherence, you must first check the logic and flow of your draft to ensure readers can see the big picture you are trying to create.

Reverse Outlining

Let’s face it: the process of writing a draft can be hectic, messy, and confusing. Sometimes we don’t really know what we’ve written until the dust settles. Reverse outlining can help us see the overall structure of the draft, which often differs significantly from what we set out to write!

To write a reverse outline,

• Number each paragraph in your draft (write in the margin or use the comment feature in Docs or Word).
• In a separate document, write down these numbers, one per line.
• If you have trouble figuring out what the paragraph is about, make a note for yourself that the paragraph needs to be reworked.
• If the paragraph is has more than one main idea, make a note for yourself that it needs to be split in two.
• If you find a redundant paragraph that repeats a point made in another paragraph using different words, make a note to combine or differentiate the two paragraphs.
• If a paragraph doesn’t relate to the overall argument, make a note to revise or remove this paragraph.
• How does this sequence of topics help you achieve your purpose (or not)?
• Are any topics unnecessary or redundant?
• Are there any extended side-notes or rabbit-holes that risk confusing the reader?
• How could you revise and reorder paragraph topics to better accomplish your goals?

Compare the sequence of points in your reverse outline with your original outline (if you have one) to see where you diverged from your plan. Finally, you can create a new outline that represents the best possible sequence of points and revise your draft accordingly.

The following video describes reverse outlining, its benefits, and a technique you can use to reverse outline your draft.

Question Outlining

If you’re still not sure about the overall order of your argument, you can try writing an outline of questions:

• Create a new list of numbers corresponding to the paragraphs of your paper.
• For each paragraph, think about what question this paragraph is answering.
• Write this question down from the point of view of the audience.
• Does this sequence of questions reflect how a reasonable person might seek answers about your topic?
• How do the questions connect to one another?
• Does it make sense to answer some before others?
• Would it be beneficial to have these questions follow a more logical pattern of development (general to specific, or specific to general)?
• Food Pyramid. Provided by : USDA. Located at : https://en.wikipedia.org/wiki/Food_pyramid_(nutrition)#/media/File:USDA_Food_Pyramid.gif . License : Public Domain: No Known Copyright
• Writing Coherently. Provided by : Lumen Learning. License : CC BY: Attribution

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What is cohesion?

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Cohesion How to make texts stick together

Cohesion and coherence are important features of academic writing. They are one of the features tested in exams of academic English, including the IELTS test and the TOEFL test . This page gives information on what cohesion is and how to achieve good cohesion. It also explains the difference between cohesion and coherence , and how to achieve good coherence. There is also an example essay to highlight the main features of cohesion mentioned in this section, as well as some exercises to help you practise.

For another look at the same content, check out YouTube or Youku , or the infographic .

It is important for the parts of a written text to be connected together. Another word for this is cohesion . This word comes from the verb cohere , which means 'to stick together'. Cohesion is therefore related to ensuring that the words and sentences you use stick together.

Good cohesion is achieved through the following five main methods, each of which is described in more detail below:

• repeated words/ideas
• reference words
• transition signals
• substitution

Two other ways in which cohesion is achieved in a text, which are covered less frequently in academic English courses, are shell nouns and thematic development . These are also considered below.

Repeated words/ideas

Check out the cohesion infographic »

One way to achieve cohesion is to repeat words, or to repeat ideas using different words (synonyms). Study the following example. Repeated words (or synonyms) are shown in bold.

Cohesion is an important feature of academic writing . It can help ensure that your writing coheres or 'sticks together', which will make it easier for the reader to follow the main ideas in your essay or report . You can achieve good cohesion by paying attention to five important features . The first of these is repeated words. The second key feature is reference words. The third one is transition signals. The fourth is substitution. The final important aspect is ellipsis.

In this example, the word cohesion is used several times, including as a verb ( coheres ). It is important, in academic writing, to avoid too much repetition, so using different word forms or synonyms is common. The word writing is also used several times, including the phrase essay or report , which is a synonym for writing . The words important features are also repeated, again using synonyms: key feature , important aspect .

Reference words

Reference words are words which are used to refer to something which is mentioned elsewhere in the text, usually in a preceding sentence. The most common type is pronouns, such as 'it' or 'this' or 'these'. Study the previous example again. This time, the reference words are shown in bold.

Cohesion is an important feature of academic writing. It can help ensure that your writing coheres or 'sticks together', which will make it easier for the reader to follow the main ideas in your essay or report. You can achieve good cohesion by paying attention to five important features. The first of these is repeated words. The second key feature is reference words. The third one is transition signals. The fourth is substitution. The final important aspect is ellipsis.

The words it , which and these are reference words. The first two of these, it and which , both refer to 'cohesion' used in the preceding sentence. The final example, these , refers to 'important features', again used in the sentence that precedes it.

Transition signals, also called cohesive devices or linking words, are words or phrases which show the relationship between ideas. There are many different types, the most common of which are explained in the next section on transition signals . Some examples of transition signals are:

• for example - used to give examples
• in contrast - used to show a contrasting or opposite idea
• first - used to show the first item in a list
• as a result - used to show a result or effect

Study the previous example again. This time, the transition signals are shown in bold. Here the transition signals simply give a list, relating to the five important features: first , second , third , fourth , and final .

Substitution

Substitution means using one or more words to replace (substitute) for one or more words used earlier in the text. Grammatically, it is similar to reference words, the main difference being that substitution is usually limited to the clause which follows the word(s) being substituted, whereas reference words can refer to something far back in the text. The most common words used for substitution are one , so , and auxiliary verbs such as do, have and be . The following is an example.

• Drinking alcohol before driving is illegal in many countries, since doing so can seriously impair one's ability to drive safely.

In this sentence, the phrase 'doing so' substitutes for the phrase 'drinking alcohol before driving' which appears at the beginning of the sentence.

Below is the example used throughout this section. There is just one example of substitution: the word one , which substitutes for the phrase 'important features'.

Ellipsis means leaving out one or more words, because the meaning is clear from the context. Ellipsis is sometimes called substitution by zero , since essentially one or more words are substituted with no word taking their place.

Below is the example passage again. There is one example of ellipsis: the phrase 'The fourth is', which means 'The fourth [important feature] is', so the words 'important feature' have been omitted.

Shell nouns

Shell nouns are abstract nouns which summarise the meaning of preceding or succeeding information. This summarising helps to generate cohesion. Shell nouns may also be called carrier nouns , signalling nouns , or anaphoric nouns . Examples are: approach, aspect, category, challenge, change, characteristics, class, difficulty, effect, event, fact, factor, feature, form, issue, manner, method, problem, process, purpose, reason, result, stage, subject, system, task, tendency, trend, and type . They are often used with pronouns 'this', 'these', 'that' or 'those', or with the definite article 'the'. For example:

• Virus transmission can be reduced via frequent washing of hands, use of face masks, and isolation of infected individuals. These methods , however, are not completely effective and transmission may still occur, especially among health workers who have close contact with infected individuals.
• An increasing number of overseas students are attending university in the UK. This trend has led to increased support networks for overseas students.

In the example passage used throughout this section, the word features serves as a shell noun, summarising the information later in the passage.

Cohesion is an important feature of academic writing. It can help ensure that your writing coheres or 'sticks together', which will make it easier for the reader to follow the main ideas in your essay or report. You can achieve good cohesion by paying attention to five important features . The first of these is repeated words. The second key feature is reference words. The third one is transition signals. The fourth is substitution. The final important aspect is ellipsis.

Thematic development

Cohesion can also be achieved by thematic development. The term theme refers to the first element of a sentence or clause. The development of the theme in the rest of the sentence is called the rheme . It is common for the rheme of one sentence to form the theme of the next sentence; this type of organisation is often referred to as given-to-new structure, and helps to make writing cohere.

Consider the following short passage, which is an extension of the first example above.

• Virus transmission can be reduced via frequent washing of hands, use of face masks, and isolation of infected individuals. These methods, however, are not completely effective and transmission may still occur, especially among health workers who have close contact with infected individuals. It is important for such health workers to pay particular attention to transmission methods and undergo regular screening.

Here we have the following pattern:

• Virus transmission [ theme ]
• can be reduced via frequent washing of hands, use of face masks, and isolation of infected individuals [ rheme ]
• These methods [ theme = rheme of preceding sentence ]
• are not completely effective and transmission may still occur, especially among health workers who have close contact with infected individuals [ rheme ]
• health workers [ theme, contained in rheme of preceding sentence ]
• [need to] to pay particular attention to transmission methods and undergo regular screening [ rheme ]

Cohesion vs. coherence

The words 'cohesion' and 'coherence' are often used together with a similar meaning, which relates to how a text joins together to make a unified whole. Although they are similar, they are not the same. Cohesion relates to the micro level of the text, i.e. the words and sentences and how they join together. Coherence , in contrast, relates to the organisation and connection of ideas and whether they can be understood by the reader, and as such is concerned with the macro level features of a text, such as topic sentences , thesis statement , the summary in the concluding paragraph (dealt with in the essay structure section), and other 'bigger' features including headings such as those used in reports .

Coherence can be improved by using an outline before writing (or a reverse outline , which is an outline written after the writing is finished), to check that the ideas are logical and well organised. Asking a peer to check the writing to see if it makes sense, i.e. peer feedback , is another way to help improve coherence in your writing.

Example essay

Below is an example essay. It is the one used in the persuasion essay section. Click on the different areas (in the shaded boxes to the right) to highlight the different cohesive aspects in this essay, i.e. repeated words/ideas, reference words, transition signals, substitution and ellipsis.

Title: Consider whether human activity has made the world a better place.

History shows that human beings have come a long way from where they started. They have developed new technologies which means that everybody can enjoy luxuries they never previously imagined. However , the technologies that are temporarily making this world a better place to live could well prove to be an ultimate disaster due to , among other things, the creation of nuclear weapons , increasing pollution , and loss of animal species . The biggest threat to the earth caused by modern human activity comes from the creation of nuclear weapons . Although it cannot be denied that countries have to defend themselves, the kind of weapons that some of them currently possess are far in excess of what is needed for defence . If these [nuclear] weapons were used, they could lead to the destruction of the entire planet . Another harm caused by human activity to this earth is pollution . People have become reliant on modern technology, which can have adverse effects on the environment . For example , reliance on cars causes air and noise pollution . Even seemingly innocent devices, such as computers and mobile phones, use electricity, most of which is produced from coal-burning power stations, which further adds to environmental pollution . If we do not curb our direct and indirect use of fossil fuels, the harm to the environment may be catastrophic. Animals are an important feature of this earth and the past decades have witnessed the extinction of a considerable number of animal species . This is the consequence of human encroachment on wildlife habitats, for example deforestation to expand cities. Some may argue that such loss of [animal]   species is natural and has occurred throughout earth's history. However , the current rate of [animal]   species loss far exceeds normal levels   [of animal species loss] , and is threatening to become a mass extinction event. In summary , there is no doubt that current human activities such as the creation of nuclear weapons , pollution , and destruction of wildlife , are harmful to the earth . It is important for us to see not only the short-term effects of our actions, but their long-term ones as well. Otherwise , human activities will be just another step towards destruction .

Aktas, R.N. and Cortes, V. (2008), 'Shell nouns as cohesive devices in published and ESL student writing', Journal of English for Academic Purposes , 7 (2008) 3-14.

Alexander, O., Argent, S. and Spencer, J. (2008) EAP Essentials: A teacher's guide to principles and practice . Reading: Garnet Publishing Ltd.

Gray, B. (2010) 'On the use of demonstrative pronouns and determiners as cohesive devices: A focus on sentence-initial this/these in academic prose', Journal of English for Academic Purposes , 9 (2010) 167-183.

Halliday, M. A. K., and Hasan, R. (1976). Cohesion in English . London: Longman.

Hinkel, E. (2004). Teaching Academic ESL Writing: Practical Techniques in Vocabulary and Grammar . Mahwah: Lawrence Erlbaum Associates Inc Publishers.

Hyland, K. (2006) English for Academic Purposes: An advanced resource book . Abingdon: Routledge.

Thornbury, S. (2005) Beyond the Sentence: Introducing discourse analysis . Oxford: Macmillan Education.

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Compare & contrast essays examine the similarities of two or more objects, and the differences.

Cause & effect essays consider the reasons (or causes) for something, then discuss the results (or effects).

Discussion essays require you to examine both sides of a situation and to conclude by saying which side you favour.

Problem-solution essays are a sub-type of SPSE essays (Situation, Problem, Solution, Evaluation).

Transition signals are useful in achieving good cohesion and coherence in your writing.

Reporting verbs are used to link your in-text citations to the information cited.

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Definition of coherent

• analytical
• well-founded
• well-grounded

Examples of coherent in a Sentence

These examples are programmatically compiled from various online sources to illustrate current usage of the word 'coherent.' Any opinions expressed in the examples do not represent those of Merriam-Webster or its editors. Send us feedback about these examples.

Word History

borrowed from Middle French & Latin; Middle French coherent , borrowed from Latin cohaerent-, cohaerens "touching, adjacent, cohering," from present participle of cohaerēre "to cohere "

1557, in the meaning defined at sense 2a

Dictionary Entries Near coherent

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“Coherent.” Merriam-Webster.com Dictionary , Merriam-Webster, https://www.merriam-webster.com/dictionary/coherent. Accessed 14 Aug. 2024.

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5 Coherent Paragraphs

When you think about it, there’s no contradiction in the advice of these two American writers. You should respond with genuine feeling and without inhibition to what stimulates you – in our case, a set of texts. But feeling isn’t enough. When Gustave Flaubert asked “Has a drinking song ever been written by a drunken man?” he meant a coherent song. Between “getting it down” and “handing it in” good writers show respect for their readers by organizing their material into recognizable patterns. An important benefit of this is that by distancing yourself from your ideas and putting them in order for your reader, you are forced to shape your own nebulous feelings into clear thoughts.

This brings us to the well-known (but apparently not well enough known) paragraph: the basic unit of composition. The traditional and still useful rule that a paragraph must have unity, coherence, and emphasis only means that it must make sense, that the sentences should fit together smoothly, and that not all the sentences function in the same way.

When you see that its purpose is to support your thesis by developing and connecting your ideas meaningfully, then paragraph structure should appeal to your common sense. As a point of emphasis a topic sentence – whether you choose to put it at the beginning, middle, or end – allows you to control your writing and guide your reader by expressing the main idea of the paragraph. Remember, you’re not writing a mystery novel. There will be relatively few instances in this type of essay when you’ll want to surprise your reader.

Must every paragraph have a topic sentence? Not necessarily: if the main idea is obvious, then a topic sentence may be omitted. But even if it is only implied by your paragraph, you and your reader should be able to state easily the main idea . Whether explicit or implicit, the topic sentence of each of your paragraphs should come out of your thesis statement and lead to your conclusion. Like the paragraph, the whole essay should have unity, coherence, and emphasis. Try this: next time you read an essay, underline only the topic sentences of each paragraph; then reread only what you’ve underlined. In many cases you’ll see that the underlined sentences make up a coherent paragraph all by themselves (this is an easy way to write an abstract, incidentally). That’s because most topic sentences are more specific than the thesis statement that generates them, but still more general than the supporting sentences in the paragraphs that illustrate them. Thus they are transitions between the writer’s promise to the reader and the keeping of that promise.

Examples: Opening Paragraphs

From a student essay discussing Kafka’s The Metamorphosis :

When Nietzsche declared that “God is dead,” he did so with an air of optimism. No longer could man be led about on the tight leash of religion; a man liberated could strive for the status of Overman. But what happens if a man refuses to let go of his “dead” God and remains too fearful to evolve into an Overman? Rejecting the concept of the Christian God means renouncing the scapegoat for the sins of man and accepting responsibility for one’s own actions. In The Metamorphosis Gregor Samsa plays the god-like role of financial provider for his family. However, when his transformation renders him useless in this role, the rest of Samsa’s family undergoes a change of its own: Kafka uses the metamorphoses of both Gregor and his family to illustrate a modern crisis.

Some comments on the structure:   Two provocative introductory sentences, then a transition question and a response that presents the central idea of the essay. Next, introduction of the text and characters under discussion. Finally, the topic sentence of the paragraph, which, as the thesis statement, promises an interpretation. A paragraph such as this engages the reader’s interest right away and makes the reader look forward to the rest of the essay.

From a student essay on the question, “What Do Historians of Childhood Do?”

In his 1982 book The Disappearance of Childhood , Neil Postman argues that the concept of childhood is a recent invention of literate society, enabled by the invention of moveable-type printing. Postman says as a result of television, literate adulthood and preliterate childhood are both vanishing. While Postman’s indictment of TV-culture is provocative, he ignores race, class, ideology, and economic circumstance as factors in the experience of both children and adults. Worse, he ignores history, making sweeping generalizations such as the claim that the pre-modern Greeks had no concept of children. These claims are contradicted by the appearance of children in classical Greek literature and in the Christian Gospels, written in Greek, which admonish their readers to “be as children.” A more useful and much more interesting observation might be that the idea of childhood and the experience of young people has changed significantly since ancient times, and continues to change.

Some comments on the structure:   Like the previous example, this essay begins with a statement from a text (this time with a paraphrase rather than a quotation) and builds towards a thesis statement. In this case the build-up, where the writer disagrees with one of the class texts, is stronger than the thesis. The writer has not stated exactly what he will argue, aside from saying he finds at least some of the ideas of childhood advanced in the course materials unsatisfactory. Keeping the reader in suspense may add to the interest of the essay, but in a short paper it might also waste valuable time and leave the reader unsure whether the writer has really thought things through.

From an essay on Crime and Punishment :

“Freedom depends upon the real…It is as impossible to exercise freedom in an unreal world as it is to jump while you are falling” (Colin Wilson, The Outsider, p. 39). Even without God, modern man is still tempted to create unreal worlds. In Feodor Dostoevsky’s Crime and Punishment Raskolnikov conceives the fantastic theory of the “overman.” After committing murder in an attempt to satisfy his theory, Raskolnikov falls into a delirious, death-like state; then, Lazarus-like, he is raised from the “dead.” His “resurrection” is not, as some critics suggest, a consequence of his love for Sonya and Sonya’s God. Rather, his salvation results from the freedom he gains when he chooses to live without illusions.

Comments: Once more, a stimulating opening. Between the first and last sentences, which frame the paragraph (the last one, as well as being the thesis sentence, is the specific application of the general first sentence), the writer makes her transition to the central idea and introduces the text and character she wishes to discuss. The reader is given enough information to know what to expect. It promises to be an interesting essay.

Each of the writers above chooses to open with a quotation or reference that helps to focus the reader’s attention and reveal the point of view from which a specific interpretation will be made. Movement from the general to the specific is very common in introductory thesis paragraphs, but it is not obligatory. You can begin with your thesis statement as the first sentence; start with a question; or use the entire opening paragraph to set the scene and provide background, then present your thesis in the second paragraph. Make choices and even create new options, so long as your sentences move to create a dominant impression on the reader.

Examples: Middle Paragraphs

From a student essay comparing P’u Sung-ling’s (17th century) The Cricket Boy and Franz Kafka’s (20th century) The Metamorphosis , two stories that deal with a son’s relationship to his family. (The writer’s thesis: according to these authors, one must connect in meaningful ways with other human beings in order to achieve what Virginia Woolf calls “health,” “truth,” and “happiness.”)

The most obvious similarity between Kiti and Gregor is that they both take the forms of insects; however, their and their families’ reactions to the changes account for the essential difference between the characters. Whereas Kiti thinks a cricket represents “all that [is] good and strong and beautiful in the world ( Cricket Boy , p. 2), Gregor is repulsed by his insect body and “closes his eyes so as not to have to see his squirming legs” ( Metamorphosis , p, 3). Their situations also affect their families differently.  Kiti’s experience serves as a catalyst that brings his family closer together: “For the first time, his father had become human, and he loved his father then” ( CB , p. 2). Gregor’s transformation, on the other hand, succeeds in further alienating him from his family: his parents “could not bring themselves to come in to him” ( M , p. 31). While Kiti and his parents develop a bond based on understanding and mutual respect, Gregor becomes not only emotionally estranged from his family, but also physically separated from them.

Some comments on the structure:   The writer is clearly on her way, with specific examples from the texts, to supporting her argument concerning the need for self-respect and communication. Notice that she uses transitions such as “however,” “whereas,” “also,” “on the other hand,” while,” and “not only…, but also…” to connect her thoughts and make her sentences cohere. Transitional words and phrases are the “glue” both within and between paragraphs: they help writers stick to the point, and also allow readers to stay on the path the writer intends.

Transitions

Writers use transitional words and expressions as markers to guide readers on their exploratory journey. They can express relationships very explicitly , which is often exactly what is needed. However, experienced writers can also build more subtle bridges between ideas, hinting at relationships with implicit transitions. These relationships may change from vague impressions to a very concrete statement, as the argument develops, allowing the reader to “discover” the writer’s conclusion as the essay builds to its final paragraph.

Examples of explicit transitional expressions

• Comparison: such as, like, similarly, likewise, in the same way, in comparison, correspondingly, analogous to
• Contrast: but, however, in contrast, although, different from, opposing, another distinction, paradoxically
•   Cause-effect: because, as a result, consequently, for this reason, produced, generated, yielded
•   Sequence: initially, subsequently, at the onset, next, in turn, then, ultimately
•  Emphasis: above all, of major interest, unequivocally, significantly, of great concern, notably
•   Examples: for example, in this instance, specifically, such as, to illustrate, in particular
•   Adding points: as well as, furthermore, also, moreover, in addition, again, besides

If you find that you are overusing explicit connectors and your transitions are beginning to feel mechanical (How many times have you used “furthermore” or “however”?  How many “other hands” do you have?), you can improve the flow of your writing either by changing up the transitional expressions, or by shifting toward more implicit transitions. One technique is, in the first sentence of the new paragraph, refer (either explicitly or implicitly) to material in the preceding paragraph. For example:

When Alcibiades does give his speech, we see that his example is Socrates himself.

While this interpretation still seems reasonable, I was surprised at the difficulty of uncovering useable data in the records of past societies.

This sometimes sickening detail that Dante uses to draw the reader emotionally into the Inferno also stimulates the reader to think about what he or she feels.

The Greek system is much more relaxed; obeisance and respect for the gods is not required, although in most cases it seems to make life easier.

Each of these implicit transition sentences builds on the previous paragraph and calls for support in the new paragraph. Even more subtle (that is, more difficult) would be to make the last sentence of the paragraph indicate the direction the next paragraph will take. If you try this, be careful you do not at the same time change the subject. You do not want to introduce a new idea at the end of a paragraph, and destroy its unity. Since it suggests a change in direction, we see this device used most commonly with thesis sentences at the end of introductory paragraphs, or in transitional paragraphs like the example above.

Other examples of hinges writers use to make connections include pronouns referring back to nouns in the previous paragraphs and synonyms to avoid repetition and overuse of pronouns. A good rule is not to overuse any device.

Concluding Paragraphs

From a student essay on Crime and Punishment :

Raskolnikov finally finds a new life:

Indeed he [is] not consciously reasoning at all; he [can] only feel .  Life [has] taken the place of logic and something quite different must be worked out in his mind. (Epi. II, p. 464)

Thus he ends his suffering by abandoning intelligence and reasoning.  Jean-Jacques Rousseau said that “above all the logic of the head is the feeling of the heart.” Ultimately, Raskolnikov transcends the “logic of the head” by discovering love and freedom.

Some comments on the structure: The paragraph works well as a conclusion because you can tell immediately that the writer has said all that she wants to say about the subject. She uses a quotation from another source, to “rub up against” Dostoevsky, expanding the dialogue between the text, the writer, and the reader by adding another voice. The answer to the “so what?” question is implied in the last sentence: love and freedom are values we all can share. Note that although this is a different conclusion from that of the earlier essay discussing Crime and Punishment , both interpretations are interesting and valid because both writers supported their arguments with careful readings of the text.

From a History essay analyzing the influence of Philippe Ariès’s book Centuries of Childhood on later historians:

In the end, Centuries of Childhood did not establish a conceptual framework for children’s history. Nor did the rival philosophies of history create a new paradigm for children’s history. Ariès identified a subject of study. He was a prospector who uncovered a rich vein of material. Subsequent miners should use whatever tools and techniques are best suited to getting the ore out of the ground. Historians should stop fighting over theories and get to work uncovering the lives of children and families. This will involve, as Jordanova suggested, self-awareness and sensitivity. But it should not be sidetracked by ideological debates. As Cunningham observed, the stakes for modern children and families are high. To make children’s history useful for the present, historians of children and families need to put aside their differences and get back to work.

Some comments on the structure:   As in the previous example, the writer includes the perspectives of other commentators. This is especially common in essays on secondary sources in history, because “historiography” is often imagined as an ongoing conversation about primary and important secondary texts. The “so what” statement is more explicit this time, relating the study of children in the past to improving the lives of children and families today. The importance of connecting with the needs of today is problematic (many historians would criticize this as “presentism”); so the writer includes a supporting perspective from a sympathetic commentator.

From an essay in which the writer compares and contrasts the character she is examining with a character from another work:

Like Ophelia, Gretchen has moments of confusion and despair, but she decides to give in to her feelings and take responsibility for them. By having Gretchen freely stay behind to face her execution, Goethe casts aside any similarities that his character shares with Shakespeare’s Ophelia. Along with the empowering freedom of Gretchen’s striving comes the struggle to act rightly. But if no objective absolutes exist, according to Goethe’s God, on what basis can Gretchen make her decisions in order to be saved? She comes to the realization that the only absolutes exist within herself. Goethe’s God saves her, not for being a penitent Christian, but for staying true to these self-imposed absolutes.

Some comments on the structure:  Another strong conclusion. The writer’s interpretation could be contested, but she has argued it well and convincingly throughout the essay and concluded strongly. Incidentally, note also that by specifying “Goethe’s God” in her interpretation she avoids any distracting discussion of religion and keeps her writing focused on literary analysis. We don’t argue the nature of “God” in an essay about literature; only the nature of the “God” in the text.

A Short Handbook for writing essays in the Humanities and Social Sciences Copyright © 2019 by Salvatore F. Allosso and Dan Allosso is licensed under a Creative Commons Attribution-NonCommercial-ShareAlike 4.0 International License , except where otherwise noted.

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/koʊˈhɪrənt/, /kəʊˈhɪərɪnt/.

Something coherent is logical and clear. "I told you if you didn't do your homework you couldn't watch TV. You didn't do your homework so you can't watch TV." This is a coherent argument (and annoying as well).

The thing about such coherent arguments, as your Mom well knows, is that they are also easily and clearly understood. If someone speaks coherently, they are speaking clearly and lucidly. A slight variation on the meaning comes in the sense of something that is united clearly as a whole and a recognizable entity. You might say, for example, that New York City is a "culturally coherent region" within the United States.

• adjective marked by an orderly, logical, and aesthetically consistent relation of parts “a coherent argument” synonyms: consistent , logical , ordered seamless perfectly consistent and coherent logical capable of or reflecting the capability for correct and valid reasoning rational consistent with or based on or using reason see more see less antonyms: incoherent without logical or meaningful connection confused , disconnected , disjointed , disordered , garbled , illogical , scattered , unconnected lacking orderly continuity fuzzy confused and not coherent; not clearly thought out illogical , unlogical lacking in correct logical relation irrational not consistent with or using reason show more antonyms...
• adjective (physics) of waves having a constant phase relation see more see less antonyms: incoherent (physics) of waves having no stable definite or stable phase relation
• adjective capable of thinking and expressing yourself in a clear and consistent manner “she was more coherent than she had been just after the accident” synonyms: logical , lucid rational consistent with or based on or using reason
• adjective sticking together “two coherent sheets” synonyms: tenacious adhesive tending to adhere

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co•her•ent

• abstract thought
• analytic thinking
• antinovelist
• anti-submarine rocket
• articulated
• articulation
• audio system
• automatic data processing system
• basic point defense missile system
• cognitively
• coherent control
• coherent light
• Cogswell chair
• cohabitation
• Cohan George Michael
• Cohen Stanley
• Cohen Stanley Norman
• cohesibility
• cohesionless
• cohesionless soil
• Cohesive attraction
• cohesive soil
• cohesiveness
• Cohn Ferdinand Julius
• Cohn Roy Marcus
• coho salmon
• cohered video
• Coherence (physics)
• Coherence and Electromagnetic Fields in Biological Systems
• coherence area
• Coherence Cube Technology
• coherence distance
• Coherence in Information for Agricultural Research for Development
• Coherence length
• Coherence time
• Coherence Time Interval
• coherencies
• Coherent Acoustic Sediment Probe
• Coherent Acoustic Torpedo System
• Coherent Adaptive Antenna
• Coherent Adaptive Antenna Array
• Coherent Adaptive Antenna Array Diversity
• Coherent Adaptive Array Antenna Rake
• Coherent Adaptive Array Diversity
• Coherent Adaptive Subcarrier Modulation
• Coherent Additive White Gaussian Noise
• Coherent Amplitude Detector
• Coherent and Electro-Optics Research Group
• Coherent anti-Stokes Raman spectroscopy
• Coherent Antipodal
• Coherent Antistokes Raman
• Coherent Automated Target Simulator
• Coherent backscattering
• Coherent Backscattering Opposition Effect
• Coherent Binary Phase-Shift Keying
• coherent carrier system
• Coherent Carrier Wave
• Coherent Change Detection
• Coherent Combining
• Coherent Complete Partial Order
• Coherent Correction Factor
• Coherent Correlation Receiver
• Coherent Data Collection System
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JSmol Viewer

Improved coherent processing of synthetic aperture radar data through speckle whitening of single-look complex images  †.

1. Introduction

2. materials and methods, 2.1. speckle whitening of complex sar data, 2.1.1. sar system: an overview, 2.1.2. problem formulation.

Click here to enlarge figure

2.1.3. Point Targets

2.2. insar processing, non-local filtering of interferogram, 3.1. cosmo-skymed dataset.

• Without a Hamming window, starting from raw data;
• With a Hamming window, starting from raw data;
• With a Hamming window and then spatially decorrelated.

3.2. TerraSAR-X/TanDEM-X Dataset

4. discussion, 5. conclusions, author contributions, data availability statement, acknowledgments, conflicts of interest.

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Share and Cite

Alparone, L.; Arienzo, A.; Lombardini, F. Improved Coherent Processing of Synthetic Aperture Radar Data through Speckle Whitening of Single-Look Complex Images. Remote Sens. 2024 , 16 , 2955. https://doi.org/10.3390/rs16162955

Alparone L, Arienzo A, Lombardini F. Improved Coherent Processing of Synthetic Aperture Radar Data through Speckle Whitening of Single-Look Complex Images. Remote Sensing . 2024; 16(16):2955. https://doi.org/10.3390/rs16162955

Alparone, Luciano, Alberto Arienzo, and Fabrizio Lombardini. 2024. "Improved Coherent Processing of Synthetic Aperture Radar Data through Speckle Whitening of Single-Look Complex Images" Remote Sensing 16, no. 16: 2955. https://doi.org/10.3390/rs16162955

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