Koyomi: Do you know about the “most beautiful formula in mathematics history”? It’s eiπ+1=0, what people call Euler’s Identity. The natural logarithmic base e, the ratio of circumference to diameter pi, the imaginary number i, 1, and 0 all fit into this equation with nothing superfluous, and fit in such a way that it was meant to be. If there is a god in this world, this is a piece of evidence that will be listed as one of the most credible.
Narration: What’s amusing, or at least beautiful, is that this formula was “predetermined.” It’s beautiful, but when you think about it, it’s also scary.
Koyomi: And yet, Oshino Ougi – that transfer student – just might throw out some candid advice even for the beauty of Euler’s Identity, just like this:
Ougi: Yes. It indeed is beautiful, Araragi-senpai. Beautiful, so beautiful, it just makes me swoon. The most beautiful part about it is that the answer is zero. That said, someone like me thinks that if the answer is going to be zero there’s really no need to go out of your way to make the calculation.
Koyomi: Hearing that, I reconfirm my belief; Oshino Ougi is Oshino Ougi, and there’s no way to express it. Before her, everything is zero. No matter what she does that may seem out of character, it always ends up being something characteristic of her. And so, this time, we have a story about mathematics. Let’s study. People tend to brace themselves when they hear “mathematics”. So we can break it down and say this is a story about “arithmetic” instead. While we’re at it, we can be more blunt and say this is a story about “numbers”. After all, this is a story where the strength in numbers provides a solution. In other words, it’s a story about majority rule.