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The Thesis Statement

A thesis is an assertion a writer makes, one that must be proven by the rest of the paper. The thesis boldly declares something that must be supported, explained, and proven. A thesis is not an obvious truth or fact; such things do not need to be proven. This sentence functions as a roadmap for the entire paper, laying out the basic components of the argument to follow and giving the reader an idea of where the paper is going to go. Frequently, a surprised reader is a confused reader.

The thesis and the paper must match each other. If the two do not match, one or the other needs to change. Writing is a dynamic process rather than a spelling out of pre-formed ideas, so your thesis may very well change over the course of writing and revising your paper. For this reason, you will want to begin writing with what is called a working thesis. Once the paper nears completion, the working thesis should be hammered out into a vibrant and concise thesis statement. You may even wish to begin with a question as a working thesis, but be sure to leave plenty of revision time to determine the answer to that question and pull it together into a tight, assertive statement.

One problem writers encounter when writing theses is the temptation to write statements of feeling or statements of fact. These may be interesting, but they are not theses. An effective thesis must be arguable. If it is just a known or general statement, then why should the reader be interested? In order to be arguable, a thesis should have three characteristics: it must be restricted, unified and precise. 


To be restricted, a thesis must limit the scope of an essay to what can be discussed in detail within the perimeters of the paper's expected length. For example, you would not have the following thesis for a four-page paper: 

"The United States has a serious problem with gangs." 

This thesis is too general, something you would need to write a book (or at least a long research paper) to prove. A better thesis for a relatively short paper would be: 

"In Chicago, gang activity has hindered the educational effectiveness of the public high schools." 

Notice that the words Chicago, educational effectiveness, and high schools all serve to narrow the focus of the thesis, and therefore make the paper more manageable to write. 


Also, a thesis must be unified; in other words, it must express only one idea. Consider what is wrong with this thesis:

"Gang-related murders have increased significantly in the past fifteen years, and new gang member initiates are younger each year, making the job of controlling gangs even more difficult for police." 

The problem with this thesis is that it commits the writer to three different topics: 1) the increase of gang-related murders; 2) the initiation of younger gang members; and 3) the problem of gang control by police. When a thesis uses a coordinating sentence, containing two or more parts, it is important that all of the parts are closely related so that the focus of the paper is not diffused. For example: 

"Chicago's mayor needs to work harder to curb gang violence by increasing the number of police patrols in gang-infiltrated neighborhoods, pressing the courts for stiffer sentences for gang offenders, and establishing an educational campaign to teach children how to resist gang involvement." 

All of these coordinated parts of the sentence center around what the mayor of Chicago could and should do to solve the gang problem in the city.


Furthermore, a good thesis is precise, meaning that when it is read it can only have one interpretation. Vague words should be avoided, and abstract words may be problematic, unless the paper is dealing with an abstract issue. For example, a philosophy paper on "phenomenology" may require more abstract language than a history paper on Abraham Lincoln's Emancipation Proclamation. Generally, try to make the thesis as clear and specific as possible, fleeing from words that express nondescript meaning, such as unusual, interesting, inspiring, or important, to name a few. This thesis:

"Gang life, which resembles family life, is fascinating."

would be more precisely stated:

"Members of a gang generally interact in a manner that resembles a family, and the parallels between the two social groups are strikingly similar."

A thesis with precise language makes for a better argument, one which a reader is more apt to understand and acknowledge.

Finally, a thesis sentence is most often expressed in a single sentence. The thesis sentence is generally found at the end of a well developed introductory paragraph.

Writing in the Disciplines

All papers need theses of some type; however, the type of thesis and style of thesis that each paper requires may differ, particularly by discipline. 

Writing in the natural sciences (mathematics, biology, chemistry, botany, physiology, etc.)

Generally speaking, your thesis will be objective. This does not mean, however, that you should forget about the thesis statement altogether. In the natural sciences, it is most important to write an exact and complete statement, using concrete data and research to report your selected topic and/or findings.

It is also possible to write a persuasive, non-objective scientific thesis statement. If this is the case, you must still follow the exact and complete rule, but refer to the previously discussed guidelines to make your statement shine with persuasive power.

Writing in the social sciences (theology, history, psychology, sociology, anthropology, etc.)

Generally, within the social sciences, your thesis will relate to a claim made about a particular, observed behavior or concept. Therefore, the key word for social scientists is persuasion. Use concrete, specific research to persuade your selected audience of your argument.

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