Sherlock Holmes is a cat. John H. Watson is a dog.
Holmes with his famous "cat-like love of personal cleaniness." His causing of the occasional suspect to exclaim, "You can't just sit there and play with me like a cat with a mouse!" His reference to criminals as "my natural prey."
And Watson . . . well, Lestrade may get all the "bulldog" quotes, but Watson isn't that kind of dog. He is man's best friend to a particular man, which no one will dispute. He has "that grand gift of silence," which means he'll sit there and listen. And when you need him to chase something, he'll chase it. "I am a dog-fancier myself," Sherlock Holmes once said, perhaps bending the truth a bit for the circumstances -- he did have a habit of causing the death of canines on occasion. But Sherlock Holmes did value a loyal and trusted companion, so maybe he wasn't speaking of the exact species, and a more metaphoric "dog" instead.
There is something about the cool intensity a cat can muster that just evokes Sherlock Holmes. I noticed that when playing with my cat this evening, a feline who has been through two Sherlockian owners. A dog will chase, attack, and fight, yes, but they always seem so angry about it.
And it's interesting to see whom Sherlock Holmes thinks is like a cat: the Baron Adelbert Gruner.
"A purring cat who thinks he sees prospective mice." "A precise, tidy cat of a man." "An excellent antagonist, cool as ice, silky voiced and soothing as one of your fashionable consultants."
Baron Gruner could almost have been Sherlock Holmes, given better motivations in another life.
And who always wins in a fight between a cat and a cat? Well, the cat that brings an extra kitty to help him of course! So it goes with Holmes and Gruner, quite literally.
Sherlock Holmes is a cat in a world full of dogs, really. Helpful dogs like Toby and Pompey. Troubled dogs like Roy or one of the Carlos. Nameless victim dogs. Legendary hell-curse dogs. Dogs that were not dogs at all.
And in the end, I think a non-Canonical Sherlock quote describes Holmes and dogs the best. (Isn't it wonderful that we have such things!) And that bit of paraphrase goes like this:
Sherlock was on the side of the dogs . . . but don't think for a second he was one of them.