It is only goodness which gives extras, and so I say again that we have much to hope from the flowers.

Life, my dear Watson, is infinitely stranger than fiction; stranger than anything which the mind of man could invent. We could not conceive the things that are merely commonplace to existence. If we could hover over this great city, remove the roofs, and peep in at the things going on, it would make all fiction, with its conventionalities and foreseen conclusions flat, stale and unprofitable.

No man lives or has ever lived who has brought the same amount of study and of natural talent to the detection of crime which I have done.

Everything comes in circles. [...] The old wheel turns, and the same spoke comes up. It's all been done before, and will be again.

The emotional qualities are antagonistic to clear reasoning.

There seems to me to be absolutely no limit to the inanity and credulity of the human race. Homo Sapiens! Homo idioticus!

Philosophy, astronomy, and politics were marked at zero, I remember. Botany variable, geology profound as regards the mud stains from any region within fifty miles of town, chemistry eccentric, anatomy unsystematic, sensational literature and crime records unique, violin player, boxer, swordsman, lawyer, and self-poisoner by cocaine and tobacco.