“explained, “A man’s brain is like an empty attic. You have to put in whatever furniture you choose. A fool takes in everything he comes across, so that there is no room for anything useful to find a place, or else the useful information gets so jumbled up with everything else that he has difficulty laying his hands upon it. Now the skillful workman is very careful 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 grow to any extent. Depend upon it that there comes a time when for every piece of knowledge you add, you forget something that you knew before. It is of the highest importance, therefore, not to have useless facts elbowing out the useful ones.”