Conclusions
An effective conclusion seeks to solidify a paper's argument in the reader's mind as succinctly as possible. It provides a basis for further reflection on the issues addressed by the composition, but ensures that the reader will consider these issues with the final sentence of your essay resounding in his head.
The conclusion of your paper should accomplish three things:
It should briefly summarize your argument: Try to avoid simply rehashing your argument. Instead, devote a sentence or two on bringing the argument (your thesis) into sharp focus, and then add value by exploring new ground.
It should offer new insight: Your conclusion should be distinct from the body of your paper, but should build on the evidence you've explored. When you bring up new ideas, be sure they demonstrate how your essay fits into a larger context. For example, you might mention (1) how the issues discussed are particularly important to consider (perhaps they affect the reader in a profound manner?), (2) the current status of the issue if your paper addresses some contemporary controversy (are things being done to resolve the issue? are they sufficient? Get your reader to ask these questions), or (3) how an academic argument can be applied to non-academic issues (e.g., what does Lear's revelation tell us about ourselves?)
It should provide the reader with a sense of closure: By the time a reader has finished a piece of writing he should both understand the argument put forth in that piece and be relatively well-equipped to reflect on the issue independently. The last sentence of your paper concludes your attempt to make an impression on him: the last sentence is what, in the words of F.L. Lucas, "reverberate[s] in the reader's mind." To give the reader a sense of closure, you might: (1) end with a clever turn of phrase (as in the above example) or reinvent a clicheé, (2) end with an appropriate quotation that you find particularly eloquent (this can be extremely effective if it contains imagery that is important elsewhere in the paper and that is redefined or reemphasized by the quote), (3) return to your introduction (if you told an anecdote reinterpret it in light of what your paper has explained; if you described a scene demonstrate how the reader's perception of that scene has been changed by what he has just learned, etc.), or (4) if your essay has been a discussion of a problem, propose a possible solution.
When writing a conclusion, it is helpful to re-read your introduction and ask yourself if you've lived up to the goals you established in the first paragraph. Because writing is an act of discovery it is not uncommon to realize at the end of your paper that your conclusions don't match what you set out to do. When this is the case, adjust your introduction and conclusion to more accurately reflect what your paper argues.
BIBLIOGRAPHY (for further information . . .)
Booth, Wayne C., Gregory G. Colomb, and Joseph M. Williams. The Craft of Research. Chicago, Illinois: The University of Chicago Press, 1995. 250-54.
Trimble, John R. Writing With Style: Conversations on the Art of Writing. Englewood Cliffs, NJ: Prentice-Hall, 1975. 55-8.