Vigorous writing is concise. A sentence should contain no unnecessary words, a paragraph no unnecessary sentences, for the same reason that a drawing should have no unnecessary lines and a machine no unnecessary parts. This requires not that the writer make all his sentences short, or that he avoid all detail and treat his subjects only in outline, but that every word tell.
The surest way to arouse and hold the reader's attention is by being specific, definite, and concrete. The greatest writers — Homer, Dante, Shakespeare — are effective largely because they deal in particulars and report the details that matter. Their words call up pictures.
Make definite assertions. Avoid tame, colorless, hesitating, non-committal language. Use the word not as a means of denial or in antithesis, never as a means of evasion.