The Elements of Style

"Style is an increment in writing. When we speak of Fitzgerald's style, we don't mean his command of the relative pronoun, we mean the sound his words make on paper. All writers, by the way they use the language, reveal something of their spirits, their habits, their capacities, and their biases. This is inevitable as well as enjoyable. All writing is communication; creative writing is communication through revelation - it is the Self escaping into the open. No writer long remains incognito.
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Young writers often suppose that style is a garnish for the meat of prose, a sauce by which a dull dish is made palatable. Style has no such separate entity; it is nondetachable, unfilterable. The beginner should approach style warily, realising that it is an expression of self, and should turn resolutely away from all devices that are popularly believed to indicate style - all mannerisms, tricks, adornments. The approach to style is by way of plainness, simplicity, orderliness, sincerity.
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Style takes it final shape more from attitudes of mind than from principles of composition, for, as an elderly practitioner once remarked, "Writing is an act of faith, not a trick of grammar." This moral observation would have no place in a rule book were it not that style is the writer, and therefore what you are, rather than what you know, will at last determine your style. If you write, you must believe - in the truth and worth of the scrawl, in the ability of the reader to receive and decode the message. No one can write decently who is distrustful of the reader's intelligence, or whose attitude is patronising."

- Strunk and White, 'The Elements of Style'