The thesis statement is the most important sentence in an essay, as it contains the controlling idea for the entire work. Each body paragraph of the essay is geared towards either supporting the thesis, explaining the thesis, or providing examples of it, depending on the genre of essay.
A strong thesis statement should:
- not be too broad or too narrow: it should be general but arguable, and specific but not self-evident.
- be a declarative statement; i.e. should not announce the writer's intent (e.g. "In this essay, I will...")
Narrowing a Topic to a Thesis Statement
All academic writing is geared towards a field or a discipline, for example, philosophy or sociology or economics. These correspond to the departments on an average university campus. Within disciplines there are many topics, such as ancient Greek ethics, theories of social construction, or contemporary western economic theories of saving; these correspond to individual courses at a university in that they are a specific section of a field of study, but general enough to comprise a variety of issues or discussions. Good academic writing is situated within a discipline and related to a topic, but it must begin with an issue or a discussion.
Take microeconomic saving habits for example: in this unit, Laurie Santos raises the issue of whether humans' saving habits are rational or irrational, and how these habits have evolved. This is an excellent jumping off point for an essay: all that remains is to choose one side of the issue, and express it clearly as an appropriately-narrow thesis statement:
e.g. Humans have inherited highly irrational saving and spending habits from their hominid ancestors, and must be conscious of these evolutionary pitfalls to succeed in their personal finances.