Trust30 Day5; Magical Strangers

I had an odd thought while watching an advertisement for an old black and white Tarzan movie. In a lot of fantasy literature there is usually a humanoid race that the author uses to exemplify some aspect of humanity. Commonly elves are the race but not always. And the author usually discusses how this race has perfected that aspect of humanity that the author is focusing on.

In a lot of historical fiction the same thing happens but instead of elves, it is the noble savage. The noble savage being portrayed as an individual or small group of individuals who are associated with a "primitive" culture the hero encounters or must interact with.

I think hollywood still does this today in films where you have a the main protagonist wrestling with a problem, the solution to said problem is provided by another character who comes from a different cultural background than the protagonist, usually a culture the protagonist's society thinks poorly of. Even science fiction uses the trope, but via an alien or someone possessed by something alien.

Why is this trope so common? Where does the need come from for a writer to present a problem for her characters to struggle with and then have the solution provided as a gift. Is it lazy writing? Or is it near impossible to represent inspiration? Isn't that what mystery writers strive to do?

I do not read mysteries. I think I have read 6 or 7 since childhood, one of the first series I ever followed as a reader were the Encyclopedia Brown books. And maybe that is where I formed the opinion that mystery writers do not use the trope of a magical stranger to solve their riddles.

But back to my point. The device of a magical stranger who has all the answers the protagonist needs. Where does this come from? Does Far Eastern literature have the same trope? Does African?

It could be simply greek influence on western literature. The gods were always providing solutions to characters in their stories. Or does this go back farther? But I do not recall Beowulf receiving aid from a magical stranger.

Of course the old testament is full of magical strangers in the form of angels. Could this literary device be the result of Judeo myth being incorporated into western culture?