>he was related to Vernet the famous painter through his grand
mother.

It is interesting to note that two great fictional detectives:
Holmes and Wimsey- both had French blood. Though very different in
character, they were both rigorously logical and supremely competent
in domains related to their chosen calling. I believe this is
because of the reputation that the French had[and to some extent
still have], of cold rationalism, or logic taken to an extreme. Any
arguments for/against this hypothesis?