From Bertrand Russell’s “How I Write“:
Until I was twenty-one, I wished to write more or less in the style of John Stuart Mill. … I had, however, already a different ideal, derived, I suppose, from mathematics. I wished to say everything in the smallest number of words in which it could be said clearly. … I would spend hours trying to find the shortest way of saying something without ambiguity, and to this aim I was willing to sacrifice all attempts at aesthetic excellence.
At the age of twenty-one, however, I came under a new influence that of my future brother-in-law, Logan Pearsall Smith. He was at that time exclusively interested in style as opposed to matter. His gods were Flaubert and Walter Pater, and I was quite ready to believe that the way to learn how to write was to copy their technique. He gave me various simple rules, of which 1 remember only two: “Put a comma every four words”, and “never use ‘and’ except at the beginning of a sentence”. His most emphatic advice was that one must always re-write. I conscientiously tried this, but found that my first draft was almost always better than my second. This discovery has saved me an immense amount of time. I do not, of course, apply it to the substance, but only to the form. When I discover an error of an important kind I re-write the whole. What I do not find is that I can improve a sentence when I am satisfied with what it means.
… In fact, all imitation is dangerous. Nothing could be better in style than the Prayer Book and the Authorized Version of the Bible, but they express a way of thinking and feeling which is different from that of our time. A style is not good unless it is an intimate and almost involuntary expression of the personality of the writer, and then only if the writer’s personality is worth expressing. But although direct imitation is always to be deprecated, there is much to be gained by familiarity with good prose, especially in cultivating a sense for prose rhythm.
There are some simple maxims-not perhaps quite so simple as those which my brother-in-law Logan Pearsall Smith offered me-which I think might be commanded to writers of expository prose. First: never use a long word if a short word will do. Second: if you want to make a statement with a great many qualifications, put some of the qualifications in separate sentences. Third: do not let the beginning of your sentence lead the reader to an expectation which is contradicted by the end.