Ah, the heart. A thing so central to this series, that it can even be found as part of the title. What exactly is it though? What does it do? Since the release of the first title in the Kingdom Hearts series we've been fed information about it, and with each new title we learn a little more. We've come a long way since the beginning, but what have we learned? Can you spare a heart?
As it turns out... apparently you can. You see, long ago I formed a theory concerning how hearts could form imprints of themselves on various things. That theory is what I had used to explain various aspects of Kingdom Hearts, such as Terra's Lingering Sentiment, Nobodies, and even Xehanort's influence. Revisiting this theory with what we learned in DDD has given me a great revelation about the inner workings of the heart.
The Old Theory
"Heart Imprints" are the faded images of a heart, these images are but a shallow reflection of the true thing. It should be noted however, that these fledgling images are enough to imitate a heart. The most common example of hearts leaving imprints is during the creation of Nobodies where a heart does such to it's own body. If it were a weak imprint, a normal nobody would be created. If it were a strong imprint it'd create a human like nobody.
There's a bit more to it, but let's move on...
The New Theory
The heart imprints? You may have guessed their true nature already - they're fragments of a heart. Master Xehanort was aware of how the heart was capable of such a thing, and naturally took advantage of it. What really happens when a nobody is formed? A piece of the original heart is left behind.
Think about it, that would clarify every potential problem with nobodies. The tiniest fragment of a heart - containing nothing but the will to live, would give rise to a regular nobody. A larger fragment, containing more "data" (for lack of a better word) would create a human-like nobody. That also explains how some of the members of the organization started growing hearts of their own, as Xemnas states...
Xemnas said:A heart is never lost for good. There may have been variances in our dispositions, but a number of us unquestionably showed signs of a burgeoning replacement. Once born, the heart can also be nurtured. Our experiments creating Heartless were attempts to control the mind, and convince it to renounce its sense of self. But understand, one can banish the heart from the body, but the body will try to replace it the first chance it gets, for as many times as it takes. And so I knew, even after we were divided into Heartless and Nobodies, it was just a temporary separation.
So hearts can leave fragments, what does this mean? Well as we already know, Xehanort used this process to create more of himself. This is also a possible answer for how nobodies are formed, but what else? What more can this theory offer? Answers, that's what.
The mystery that is Terra's Lingering Sentiment can be explained by this. The unversed can be explained by this. Ansem SoD's shadow remaining in Riku can be explained by this. Heck, this might even offer some insight on the experiments done by Ansem the Wise to Apprentice Xehanort.
Thus, to answer my own question once more - Yes, you can spare a heart... part of one at least.
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I believe that covers it, comments and critique are welcome. ^_^