A onto B, and B onto A. A Brief Essay.
Among the countless stories that I have consumed over my time on this planet, one of the concepts that has been repeated multiple times is a pair of characters who both have different processes but arrive at the same goal.
For example, Clockwork Planet by Yuu Kamiya and Tsubaki Himana. In the series, without getting into too much detail, clockwork and machinery encompass the setting, in a literal "Clockwork Planet" as suggested by the name. In the story, there are two characters who are rivals of each other. The first has incredibly sensitive hearing, beyond that of the average human, to the point where he is able to accurately count the number of gears inside of an automaton in mere seconds. Despite having no talent in the actual crafting and repair of clockwork, he uses his hearing to pinpoint problems in machinery, and tinkers until the problem is solved. He is in stark contrast to another character, who was raised as a gearsmith prodigy. She understands the intended solution of a piece of equipment, and searches for the problem from that viewpoint. In the words of the author, "One arrives at the solution from the problem, and the other arrives at the problem from the solution."
The other example, specifically the one that drove me to write this essay, is from a story called Infinite Mage, by Kim Chi-Woo, where the magic system is heavily scientific, breaking it down into "Omnipotence" and "Omniscience," and this is heavily shown in the artwork and worldbuilding. The mages in this story are unable to influence the world outside of their "Spirit Zone" which is a direct manifestation of their will. This "Spirit Zone" is the Omniscience part, with the Omnipotence part being fundamental chemistry. In order for these mages to create fire, they must first fill the area with oxygen, and for them to create ice, they must remove heat from the air. Just like Clockwork Planet, there are two characters that embody this concept of A->B and B->A. One character embodies Omniscience, to the extent of an abnormally large "Spirit Zone," and applies all that he sees inside of that zone onto the fundamental understandings of chemistry that he holds, allowing to achieve results akin to mastery. Another character is the direct opposite, embodying Omnipotence. The other character uses a much deeper understanding of the world around him through advanced chemistry and even theoretical physics, and applies these principals to his "Spirit Zone," achieving similar results to the first character mentioned. Naturally they end up being rivals, but that's a discussion for another time.
I don't have an exact point with this essay, and merely wanted to express my thoughts somewhere outside of a document that nobody will see. This method of A->B and B->A with similar results is an excellent method of setting up mirroring characters and allows them to fundamentally interact in ways that allow authors a minor freedom in exclamation along with the reactions of characters outside of the duality.
That's all folks, and to all, a good night.