“A man should keep his little brain attic stocked with all the furniture that he is likely to use, and the rest he can put away in the lumber room of his library, where he can get it if he wants it.”

“Well," he said, "I say, now, as I said then, that a man should keep his little brain-attic stocked with all the furniture that he is likely to use, and the rest he can put away in the lumber-room of this library, where he can get it if he wants it.”

“I consider that a man's brain originally is like a little empty attic, and you have to stock it with such furniture as you choose. A fool takes in all the lumber of every sort that he comes across, so that the knowledge which might be useful to him gets crowded out, or at best is jumbled up with a lot of other things, so that he has a difficulty in laying his hands upon it. Now the skillful workman is very careful indeed as to what he takes into his brain-attic. He will have nothing but the tools which may help him in doing his work, but of these he has a large assortment, and all in the most perfect order. It is a mistake to think that that little room has elastic walls and can distend to any extent. Depend upon it there comes a time when for every addition of knowledge you forget something that you knew before. It is of the highest importance, therefore, not to have useless facts elbowing out the useful ones.”

“That any civilized human being in this nineteenth century should not be aware that the earth traveled round the sun appeared to me to be such an extraordinary fact that I could hardly realize it.‘You appear to be astonished,’ he said, smiling at my expression of surprise. ‘Now that I do know it I shall do my best to forget it.’‘To forget it!’‘You see,’ he explained, ‘I consider that a man’s brain is like a little empty attic, and you have to stock it with such furniture as you choose. A fool takes in all the lumber of every sort that he comes across, so that the knowledge which might be useful to him gets crowded out, or at best is jumbled up with a lot of other things, so that he has difficulty in laying his hands upon it. Now the skilful workman is very careful indeed as to what he takes into his brain-attic. He will have nothing but the tools which may help him in doing his work, but of these he has a large assortment, and all in most perfect order. It is a mistake to think that that that little room has elastic walls and can distend to any extent. Depend upon it there comes a time when for every addition of knowledge you forget something that you knew before. It is of the highest importance, therefore, not to have useless facts elbowing out the useful ones.’‘But the Solar System!’ I protested.‘What the deuce is it to me?’ he interrupted impatiently: ‘you say that we go round the sun. If we went round the moon it would not make a pennyworth of difference to me or to my work.”

“A large and comfortable double-bedded room had been placed at our disposal, and I was quickly between the sheets, for I was weary after my night of adventure. Sherlock Holmes was a man, however, who when he had an unsolved problem upon his mind would go for days, and even for a week, without rest, turning it over, rearranging his facts, looking at it from every point of view, until he had either fathomed it, or convinced himself that his data were insufficient. It was soon evident to me that he was now preparing for an all-night sitting. He took off his coat and waistcoat, put on a large blue dressing-gown, and then wandered about the room collecting pillows from his bed, and cusions from the sofa and armchairs. With these he constructed a sort of Eastern divan, upon which he perched himself cross-legged, with an ounce of shag tobacco and a box of matches laid out in front of him. In the dim light of the lamp I saw him sitting there, an old brier pipe between his lips, his eyes fixed vacantly upon the corner of the ceiling, the blue smoke curling up from him, silent, motionless, with the light shining upon his strong-set aquiline features. So he sat as I dropped off to sleep, and so he sat when a sudden ejaculation caused me to wake up, and I found the summer sun shining into the apartment. The pipe was still between his lips, the smoke still curled upwards, and the room was full of a dense tobacco haze, but nothing remained of the heap of shag which I had seen upon the previous night.'Awake, Watson?' he asked.'Yes.''Game for a morning drive?''Certainly.''Then dress. No one is stirring yet, but I know where the stable-boy sleeps, and we shall soon have the trap out.”

“By a man's finger-nails, by his coat-sleeve, by his boots, by his trouser-knees, by the callosities of his forefinger and thumb, by his expression, by his shirt-cuff — By each of these things a man's calling is plainly revealed. That all united should fail to enlighten the competent inquirer in any case is almost inconceivable. You know that a conjurer gets no credit when once he has explained his trick; and if I show you too much of my method of working, you will come to the conclusion that I am a very ordinary individual after all.”

“The weak man becomes strong when he has nothing, for then only can he feel the wild, mad thrill of despair.”