On glancing over my notes of the seventy odd cases in which I have during the last eight years studied the methods of my friend Sherlock Holmes, I find many tragic, some comic, a large number merely strange, but none commonplace; for, working as he did rather for the love of his art than for the acquirement of wealth, he refused to associate himself with any investigation which did not tend towards the unusual, and even the fantastic.

I love and am loved by a better man than he.

The ideal reasoner, he remarked, would, when he had once been shown a single fact in all its bearings, deduce from it not only all the chain of events which led up to it but also all the results which would follow from it.

It is of the highest importance in the art of detection to be able to recognise out of a number of facts which are incidental and which are vital.

Do you remember what Darwin says about music? He claims that the power of producing and appreciating it existed among the human race long before the power of speech was arrived at. Perhaps that is why we are so subtly influenced by it. There are vague memories in our souls of those misty centuries when the world was in its childhood.' That's a rather broad idea,' I remarked. One's ideas must be as broad as Nature if they are to interpret Nature,' he answered.

It is decreed by a merciful Nature that the human brain cannot think of two things simultaneously . . .

Do you know anything on earth which has not a dangerous side if it is mishandled and exaggerated?