Did Arthur Conan Doyle say “It has long been an axiom of mine that the little things are infinitely the most important.”?

Did Arthur Conan Doyle say “It has long been an axiom of mine that the little things are infinitely the most important.”?

Found word for word. Yes. The text appears in works attributed to Arthur Conan Doyle. Source and location below.

"It was most suggestive," said Holmes. "It has long been an axiom of mine that the little things are infinitely the most important. Can you remember any other little things about Mr. Hosmer Angel?"
The Adventures of Sherlock Holmes — Arthur Conan Doyle, ¶537 · Public domain (US), Project Gutenberg #1661 · source

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