Center for Communication Practices at Rensselaer (Formerly The Writing Center)

Introduction
As far as I know, there's no etymological connection between thesis and Theseus, but there is a metaphoric one. Theseus, mythical hero of ancient Greece, found his way through the Cretan Labyrinth by following a thread. Likewise, a thesis allows both reader and writer to find their ways through a labyrinth of ideas by following a thread of thought. That is, a thesis crystallizes the controlling idea of an essay and, thus, helps us to keep track of that idea as it develops through the body of the text. If we were not able to formulate theses and to understand and evaluate the theses of others, we would be hopelessly lost amidst a maze of chaotic impressions, for there is no structure to experience exclend that imposed by the human mind.

When we formulate theses, we make experience comprehensible: we organize the chaos. As researchers, we begin to pick up facts and experiences that are relevant to our theses--just as magnets pick up iron filings--and we leave what is irrelevant behind. Thus, for both reader and writer, a thesis cuts through immense confusion to make one point perfectly clear. A good thesis, then, is essential to a well-written analytical essay, and at least four things are essential to a good thesis: it must be clearly defined, adequately focused, well supported, and relatively high in the orders of knowledge.

Defining Your Thesis
Like topic sentences, theses can be simple (stated explicitly, either in one sentence or in several consecutive sentences), delayed-completion (begun in one sentence and completed at some point later in the essay), assembled (scattered in bits and pieces throughout the essay), or inferred (never explicitly stated--left for the reader to surmise) (Braddock, 310-323). But however the thesis is presented, it should be clearly defined, or, in the case of an inferred thesis, clearly definable. Even if you have chosen to use a delayed-completion, assembled, or inferred thesis, you should be able to articulate that thesis in a simple, explicit statement.

Two things happen when you fail to define your thesis clearly:

1. First, you don't know what you have committed yourself to--in fact, you may not have committed yourself to anything. As a result, your paper lacks unity. A unified essay is one in which all of your arguments, directly or indirectly, support your thesis. (Although good writers do acknowledge opposing points of view and may even concede a point here or there, they usually do so for rhetorical purposes--to enhance their own credibility by indicating that they are aware of and capable of responding to opposing views.) If you have not defined your thesis clearly, you will not know what your arguments should support. Consequently, you will ramble: some of your arguments will be irrelevant to any thesis your readers might infer; others will be contradictory. Whatever unity you achieve will be largely accidental.
2. The second consequence of an inadequately defined thesis stems directly from the first: when you don't know what you have committed yourself to, your essay lacks unity, and your readers have no thread to help them find their way through your thoughts. As you ramble, your readers grope.

Focusing Your Thesis
A thesis can be clearly defined and still lead to a rambling essay if it is not adequately focused. A good thesis narrows your topic to an idea that you can successfully develop within the framework of your essay. From the general topic of health hazards, you might propose a thesis such as, "The average American is exposed to many health hazards." This thesis, though clearly defined, is so broad that you would never be able to cover it adequately in a short essay. You would wind up either jumping from one health hazard to another, discussing each only superficially, or zeroing in on one or two health hazards and, thus, failing to demonstrate your own thesis. A more narrowly focused thesis, such as "The Constitution of the United States should be amended to prohibit the production and sale of cigarettes," commits you to an idea that you can carefully analyze and defend in four or five pages.

Supporting Your Thesis
The third requirement of a good thesis, that it be well supported, might more properly be considered a requirement of the essay as a whole. In any case, if the essay is to be effective--if it is to persuade readers of your thesis, or at least of your credibility--you must provide arguments that are cogent and numerous enough to satisfy the critical reader, and you must go on to support these arguments with facts and examples.

Orders of Knowledge
The fourth requirement of a good thesis is that it be relatively high in the orders of knowledge. Benjamin Bloom divides cognitive skills into five basic categories and arranges those categories (in ascending order of complexity) into the following hierarchy: comprehension, application, analysis, synthesis, and evaluation (Bloom, 204-207). In a similar hierarchy, Mortimer Adler divides knowledge into three classes: statements of facts, statements about facts, and statements about statements (Adler, 222-224). If your thesis falls at the lowest level of either of these hierarchies, your paper will be nothing more than a report or a survey. This is fine if that's all you intend your paper to be. But if you intend your paper to be more than a report, you must develop a thesis that is more than a statement of fact.

For example, if your "thesis" is that "In experiments conducted by the American Cancer Institue, 70 percent of the rats subjected to cigarette smoke over a two-year period died of lung cancer," your paper can hardly develop into anything more than a report about the experiments and their results. However, if you draw some conclusion from this statement of fact and make that your thesis, you advance to Adler's second order of knowledge: statements about facts. At this level, your thesis might be "Scientific experiments suggest a close link between cigarette smoking and lung cancer," or a less cautious assertion, "Cigarette smoking is the major cause of lung cancer." With either of these theses, you have an argument on your hands. You have made a statement that is not entirely self-evident, one that will not be universally agreed with, one that you will have to defend. But if you risk one step further and make a statement about this statement, you generate the spark of a potentially informative, provocative, and animated essay. For example, building on the proposition that cigarette smoking causes lung cancer, you might propose that the Constitution of the United States be amended to prohibit the production and sale of cigarettes.

Adler would classify theses of this order as statements about statements. As such, they not only encourage more stimulating essays, they also allow you to develop your essay logically by referring back to statements at the two lower levels: you present arguments (statements about facts) to support your thesis, and facts and examples (statements of fact) to support your arguments. For example, to support the thesis that the Constitution should be amended to prohibit the production and sale of cigarettes, you can draw upon the argument that cigarette smoking causes lung cancer; and to support this argument, you can draw upon the fact that in ACI experiments, 70 percent of the rats subjected to cigarette smoke died of lung cancer. Thus, theses that are statements about statements allow you to develop a layered effect that is impossible to achieve in a report or survey.

Tentative and Definitive Theses
Finally, there is an important distinction between a tentative and a definitive thesis. A tentative or working thesis is often valuable in the early stages of the writing process in that it guides your inquiry into your subject, suggesting questions, problems, and strategies. The best definitive theses, however, generally come late in the writing process. Hence, the writing process is not simply a means of codifying what you already know; it is a means of pushing beyond the commonplace, of exhausting the obvious, and of discovering what it is you ultimately want to say.

A good thesis, though essential to a good analytical essay, is not a panacea for sloppy exposition--there are scores of other things you must consider as you compose (such as style, syntax, organization, originality, punctuation, and diction). However, developing a thesis that is clearly expressed, adequately focused, well supported, and high in the orders of knowledge goes a long way toward ensuring the success of your essay.

References

• Adler, Mortimer. Dialectic. London: Kegan Paul, 1927.
• Bloom, Benjamin, ed. Taxonomy of Educational Objectives: Handbook I. New York: David McKay, 1956.
• Braddock, Richard. "The Frequency and Placement of Topic Sentences in Expository Prose." The Writing Teacher's Sourcebook. Ed. Gary Tate and Edward P. J. Corbett. New York: Oxford University Press, 1981.