Crafting the Introduction: Thesis Statements

What is the thesis statement?

The thesis statement is the central argument clearly stated early in an essay. This should appear in your introduction and tends to consist of a single sentence. In a longer or more complex work, however, the thesis statement might comprise a few sentences working together to articulate the argument.

Your thesis statement should be the cornerstone of your essay – a central focus that you consistently refer back to when developing your argument.

NOTE: If you are writing an assignment that doesn't call for a central argument, you might have an aim statement in your introduction, but no thesis statement. Aim statements are discussed in the next tab of this guide.

Refining the thesis statement

Take the time to refine your thesis statement. 'Refining' entails both reflection and action. You should reflect on the nuances and precise nature of your stance; then, take action by continuing to edit or rework your thesis until it captures your intended meaning.

• Be succinct. Again, most thesis statements will be a single sentence.
• Choose the verb(s) carefully. Are you arguing? Discussing? Analysing?
• Be specific with important adjectives and nouns. Try to avoid vague or imprecise words.

Examples of editing a thesis

Consider this example of the first draft of a thesis statement:

The British prison system has a negative impact on inmates.

This is a fine start because it at least suggests a stance or argument, but that stance isn't clear enough due to word choices. For example, by 'British prison system', does the writer mean sentencing practices, conditions of the prisons themselves, or something else? In the second draft, the writer begins to refine their thesis:

The current conditions in British prisons have a negative impact on inmates.

This is an improvement, as we now know the writer is referring to conditions within the prisons themselves. However, 'negative impact' remains vague, so the writer should take more time to reflect on the nuances or specifics of their argument. After thinking it through, the writer produces a third draft of their thesis:

This essay argues that the current conditions in British prisons are having a detrimental impact on the mental health of inmates.

Another improvement! The reader will now understand that the argument centres on harm to inmates' mental health, specifically.

The 'thesis' as 'hypothesis'

As you draft the body of your assignment, you might look back at your thesis statement and realise it no longer 'matches' the essay you have produced. Don't panic if this happens!

Throughout the writing process, our thinking may evolve as we discover new information and forge connections between ideas.

Due to this, some writers find it helpful to frame their thesis statement as a hypothesis statement until the essay is closer to completion. Just as a scientist tests a hypothesis through experimentation, a writer can test their hypothesis statement by considering the available research/evidence and applying critical thought.

If you spot a mismatch between your (hypo)thesis statement and the essay's body, the solution will depend on why the mismatch came about.

• An evolution of thought - This occurs when you expected to demonstrate or support one stance, but your thinking and research begin to suggest a different stance is more viable. In other words, the initial hypothesis has been disproven.
  • Solution - Edit your thesis statement to reflect the new (and stronger!) argument.
• Getting off track - This occurs when you have included claims and evidence that stray too far from the paper's central focus. In this scenario, the initial hypothesis hasn't been disproven; instead, you have added content that neither proves nor disproves the hypothesis.
  • Solution - Be ruthless in editing the body of your essay. Remind yourself of the central argument, and cut anything that lacks a clear connection.

Top tips 

• Write the thesis statement as clearly and simply as possible.
• In order to focus your mind on a central idea/argument, write the thesis at the top of your plan or outline. 
• Make connections between your body paragraphs and the thesis statement as a way of developing your central argument and maintaining your essay’s focus. This should happen in the analysis section of your paragraphs.
• If you detect a mismatch between your thesis statement and the essay's body, take time to diagnose the problem and edit accordingly. Treating the thesis as a hypothesis during drafting can help some writers.