It's kind of puzzling how 7 and 13 vessels are needed to forge the X-Blade when in our minds that hardly makes up a "half of each other".
I argue a simple thing and that is that light is a more potent element of the two and it produces more in terms of quality while the darkness is less "dense", thus requiring more of it to get to a 50:50 ratio in strength. So, the only way to achieve an equality in power would be to have darkness (in some number) quantitatively "bigger".
It makes sense for a lot of points in the story, besides the 7-13 bit. Take a look at what Xehanort wrote for instance: "I believe a balance of light and darkness is what sustains our World, but too much of the darkness has been stamped out, disrupting that balance. Someone must tear down this tyranny of light and reorganize the World around the darkness which then creeps back in." Now, if you want to achieve balance, filling a lot of the universe with darkness (like he was seen doing) seems counterproductive, doesn't it? Well, if the theory is true, then he seeks to balance the power of both by having a bigger part of the universe be the darkness.
It also explains why Ventus and Vanitas by themselves never granted a perfect X-Blade. They were formed by the same being and quantitatively there was an equal share of light and darkness between the two, but qualitatively they were not the same due to the difference of the properties themselves. Vanitas needed more darkness in his being to achieve that which is why it was not quite perfect.
Hell, it even proves the very basic point of why a small bit of light in a bigger darkness can overpower the darkness, as seen in so many times in the series.
But mind you, this speaks about the property of the elements, not the strength of their respective users. There is no reason why a being of darkness can't overpower a being of light if the being itself is stronger.
I argue a simple thing and that is that light is a more potent element of the two and it produces more in terms of quality while the darkness is less "dense", thus requiring more of it to get to a 50:50 ratio in strength. So, the only way to achieve an equality in power would be to have darkness (in some number) quantitatively "bigger".
It makes sense for a lot of points in the story, besides the 7-13 bit. Take a look at what Xehanort wrote for instance: "I believe a balance of light and darkness is what sustains our World, but too much of the darkness has been stamped out, disrupting that balance. Someone must tear down this tyranny of light and reorganize the World around the darkness which then creeps back in." Now, if you want to achieve balance, filling a lot of the universe with darkness (like he was seen doing) seems counterproductive, doesn't it? Well, if the theory is true, then he seeks to balance the power of both by having a bigger part of the universe be the darkness.
It also explains why Ventus and Vanitas by themselves never granted a perfect X-Blade. They were formed by the same being and quantitatively there was an equal share of light and darkness between the two, but qualitatively they were not the same due to the difference of the properties themselves. Vanitas needed more darkness in his being to achieve that which is why it was not quite perfect.
Hell, it even proves the very basic point of why a small bit of light in a bigger darkness can overpower the darkness, as seen in so many times in the series.
But mind you, this speaks about the property of the elements, not the strength of their respective users. There is no reason why a being of darkness can't overpower a being of light if the being itself is stronger.