June 15, 2004. Day fifteen of confinement. The principle of a camera is simple. In fact, without need for a lens and a mechanism for capture, the simplest camera is a mere pinprick, an opening between one thing and another. Called the "camera obscura," it is a dark room with only a small opening through which images from the outside world may be viewed. Aristotélēs (Ἀριστοτέλης) wrote of it. In the third century, in Dream Pool Essays, the philosopher Mo Di (墨翟) described the effect, saying "when a bird flies in the air, its shadow moves along the ground in the same direction. But if its image is collected through a small hole in a window, then the shadow moves in the direction opposite of that of the bird." Just as in a burning-mirror, a concave glass, which "reflects a finger to give an upright image if the object is very near, but if the finger moves farther and farther away it reaches a point where the image disappears and after that the image appears inverted. …So also the oar is fixed at the rowlock somewhere at its middle part, constituting, when it is moved, a sort of 'waist' and the handle of the oar is always in the position inverse to the end." In the early 1000's, Abū ʿAlī al-Ḥasan ibn al-Ḥasan ibn al-Haytham (أبو علي، الحسن بن الحسن بن الهيثم), who expanded on the optics of Ptolemaios (Πτολεμαῖος), observed a partial solar eclipse from inside the device. In 1558, in Natural Magic, the "professor of secrets" Giambattista della Porta, wrote "you must shut all the Chamber windows, and it will do well to shut up all holes besides, lest any light breaking in should spoil all. Only make one hole...as great as your little finger" through which the sun will shine through—then, on the far wall, the image will appear "and what is right will be the left, and all things changed."
You are in a camera obscura, a "dark chamber" now. Following that principle, you must be the reverse of whatever you were before you entered. When you lie on a sold stone floor, featureless, bare, and rough—not because you don't appreciate the thin pallet provided but because at some point in these days of tedium the textural and temperature novelty of finding new and more uncomfortable ways to rest is all that is keeping you from breaking in the silence and spitting out an unfounded confession—you wonder what Ryuga Hideki, Ryuzaki, L, would think about something that goes along the lines of: 'I am Yagami Light and I am innocent, in this jail cell, in which you can see a perfect image of myself. But because I am only an image conveyed through a pinhole lens, I must therefore have been Kira, the killer, outside of it.' You think he would be as happy to take that as he was to take the possibility of you committing crimes in a fugue state, in your sleep, or through a dual personality, which is far-fetched enough that he himself has admitted he doesn't think it likely.
All either of you are really going on here is the circumstantial evidence, which is as damning now as it had been when you confined yourself; and yet now, just as then, nothing can definitively be proven. Were you really framed by Kira? Has Kira been L the whole time?
If he is, there is no way you would know. L is not the type to gloat openly, or, you surmise, at all. He takes everything with a strange equanimity. Unless it involves discussion of things beyond this world; shinigami and the like. Wouldn't it be a funny twist if the second Kira (Misa, no doubt about it) had been speaking literally this entire time? About shinigami and eyes? If the kiras are in fact gods, or possessed by ones, how is this taskforce meant to find and defeat them?
Perhaps that was behind the source of Ryuga's terror. After all, like you, he hates to lose.
You sigh into the floor. Your eyes are gritty with lack of sleep, your hair is a greasy mess plastered over your forehead, and you didn't turn in your latest paper for Statistics. This turn of events isn't even unexpected—as far back as the first time you and Ryuga met, you brought up the idea of clearing your name to him through something like this. Of course, at the time, you'd been picturing something more akin to house arrest than being cuffed hand and foot in a cell like a common criminal; and you'd been sure that a month would be more than enough time to prove your innocence, since Kira would continue to kill while you would be in isolation. Unfortunately… Kira hasn't obliged. Three weeks, and no deaths? It isn't like him. (You've either been framed, or L is lying to you about the deaths stopping to force a confession. Or both.)
While you're waiting here, the real Kira is gloating, and you burn with rage at the thought. A possible attempt on your father's life, the fact that that his worshipper Misa saw you in Aoyama and found a way to stalk you all the way back home and become your girlfriend, the self-importance with which he toys with his enemies, with L and with you—well, you'll show him. If you have to, you'll kill him yourself.
And yet it is because Kira that you are part of the investigation of the century. It is because of Kira that you met L. You can't bring yourself to regret that, to regret any of it.
Not that you had thought so when the two of you first met…
"I've never been so humiliated in my entire life," hadn't you thought? That L or someone sent by L had so brazenly accused you, surrounded you as though you were nothing but a stone in the game of Go played out at scale between him and Kira. You had raged, actually slammed your fists onto the desk and seethed. But because you also hate to lose (it is true that this is a trait shared between you and L and the first Kira) you soon decided how to play it, and even spoke as though L could hear your vow: "I'll make you trust me. And when I've finally proved my innocence to you, I'll go one further. I'll catch Kira myself."
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