I was listening to a very interesting Sherlock Holmes story-- "The Saviour of Cripplegate Square" of The Further Adventures of Sherlock Holmes written by Bert Coules (based on cases Holmes mentions in passing during the actual Conan Doyle mysteries)-- and heard some extremely interesting and useful quotations.

The following quotations are taken from an exchange between a young Sherlock Holmes and Mr. Nathaniel Collington Smith, a librarian in the British Library reading room, during a flashback in the story:

Smith: "Librarians don't read books, Mr. Holmes. They simply know about them.... "

......

Smith and Holmes are discussing a book that Smith alleges might be unsound in its reasoning.

Holmes: "Take it [the book] back."

Smith: "Why?"

Holmes: "I have no wish to clutter my mind with useless information."

Smith: "My dear Sir-- Your mind may not have elastic walls but it does at least have an entrance and an exit. Read the book. Decide for yourself what to retain. One can learn from the unsound as well as the sound, you know. Surely they taught you that at the university."

This last pearl of wisdom should be kept in mind more often in our modern lives.