If you want to concentrate deeply on some problem, and especially some piece of writing or paper-work, you should acquire a cat. Alone with the cat in the room where you work ... the cat will invariably get up on your desk and settle placidly under the desk lamp ... The cat will settle down and be serene, with a serenity that passes all understanding. And the tranquility of the cat will gradually come to affect you, sitting there at your desk, so that all the excitable qualities that impede your concentration compose themselves and give your mind back the self-command it has lost. You need not watch the cat all the time. Its presence alone is enough. The effect of a cat on your concentration is remarkable, very mysterious.
Something amazing happens when the rest of the world is sleeping. I am glued to my chair. I forget that I ever wanted to do anything but write. The crowded city, the crowded apartment, and the crowded calendar suddenly seem spacious. Three or four hours pass in a moment; I have no idea what time it is, because I never check the clock. If I chose to listen, I could hear the swish of taxis bound for downtown bars or the soft saxophone riffs that drift from a neighbor's window, but nothing gets through. I am suspended in a sensory deprivation tank, and the very lack of sensation is delicious.
It is one of the unexpected disasters of the modern age that our new unparalleled access to information has come at the price of our capacity to concentrate on anything much. The deep, immersive thinking which produced many of civilization's most important achievements has come under unprecedented assault. We are almost never far from a machine that guarantees us a mesmerizing and libidinous escape from reality. The feelings and thoughts which we have omitted to experience while looking at our screens are left to find their revenge in involuntary twitches and our ever-decreasing ability to fall asleep when we should.