source: http://www.economist.com/styleguide/introduction

Long paragraphs, like long sentences, can confuse the reader. “The paragraph”, according to Fowler, “is essentially a unit of thought, not of length; it must be homogeneous in subject matter and sequential in treatment.” One-sentence paragraphs should be used only occasionally.

Clear thinking is the key to clear writing. “A scrupulous writer”, observed Orwell, “in every sentence that he writes will ask himself at least four questions, thus: What am I trying to say? What words will express it? What image or idiom will make it clearer? Is this image fresh enough to have an effect? And he will probably ask himself two more: Could I put it more shortly? Have I said anything that is avoidably ugly?”

Message/Words/Idioms/Freshness