'Delightedly he seized hold of the bag containing the sugar and poured sugar into the coffee cup until it was piled above the rim," writes one biographer of Søren Kierkegaard. "Next came the incredibly strong black coffee, which slowly dissolved the white pyramid." The Danish philosopher was overdoing it: perhaps it's no coincidence that his books include Fear And Trembling and The Sickness Unto Death. But coffee addicts, myself included, relish anecdotes such as this because they reinforce our belief that coffee and creativity are linked. It's not merely that caffeine is the "acceptable addiction", as it's sometimes called; it's something actively to boast about: "Oh, you don't want to meet me before my morning coffee," we say, with something close to pride. Try replacing "coffee" in that sentence with "heroin". The effect isn't quite the same.