Like an onion that is peeled, revealing multiple layers, a writing document may have multiple purposes. A persuasive essay, for example, may have paragraphs that inform, paragraphs that persuade, paragraphs tha threaten, and paragraphs that request information. However, on a more global level, each document must have one primary purpose.
Until you know your primary purpose for writing, you cannot know what information to leave in or leave out or even how to best organize a document. Of course, some academic documents have multiple purposes.
People write documents for countless reasons:
Textbooks, English instructors, and writers occasionally call the purpose statement the thesis sentence. In school contexts, some instructors require students to place the thesis statement in the introductory paragraphs. Likewise, writers of essays appearing in newspapers, magazines, and books present their thesis up front. The advantage of this deductive approach is that readers immediately know what the topic is and the writer's stance toward the subject. In contexts where the subject isn't likely to result in an emotional reaction from readers, explicit statements of purpose make sense.
When Should You Consider Your Purpose?
Because of the generative nature of the writing process, your sense of the primary purpose for a document will often become clearer once you have written a few drafts. Yet because the effectiveness of a document is chiefly determined by how well you focus on addressing a primary purpose, you can save time by identifying your purpose as early as possible.
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