"It is a question of cubic capacity," said he; "a man with so large a brain must have something in it." - Arthur Conan Doyle

I am a brain, Watson. The rest of me is a mere appendix.

Watson: When do we start?
Holmes: You are not coming.
Watson: Then you are not going. I give you my word of honour - and I never broke it in my life - that I will take a cab straight to the police station and give you away unless you let me share this adventure with you.

It is a mistake to confound strangeness with mystery. The most commonplace crime is often the most mysterious because it presents no new or special features from which deductions may be drawn. This murder would have been infinitely more difficult to unravel had the body of the victim been simply found lying in the roadway without any of those outré and sensational accompaniments which have rendered it remarkable. These strange details, far from making the case more difficult, have really had the effect of making it less so.