In the 19th century it was common to write standing up at a writing desk, leaning on a high stool. Thus we find that (presumably amongst many others) Lewis Carroll, Winston Churchill, Charles Dickens, Ernest Hemingway*, Thomas Jefferson, Fernando Pessoa, George Sand and Virginia Woolf all wrote standing up. And Philip Roth does today.
Conversely, Marcel Proust, Mark Twain and Woody Allen wrote in bed.
* despite the fact that his first rule for aspiring writers was "Apply the seat of the pants to the seat of a chair".
mjones (thanks) and: Lunatics, authors, and getting black on white, The Hemingway Lifestyle, "Conversations with Ernest Hemingway" edited by Matthew J. Bruccoli, the J Peterman furniture collection (!), Mimesis: Representing the Arts in Western Literature (Woolf), Guardian profile of Philip Roth, Ferdinando Pessoa Meets Lord Oxford, and A blank page, which picks up many more eccentric approaches to writing, culled from Hendrickson's The Literary Life & Other Curiosities.
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