The existence of heartless

[solstice]

Nomura said that this new enemy was the ancestor to the heartless and the nobodies, but who is to say that the new enemy isn't made of light and darkness?

A person is made up of a body, heart, and soul right? A heartless is created when a heart is lost to darkness, and a nobody is made from the body and soul left behind. Since a nobody doesn't have a heart, it is made out of nothing instead of light and dark. But what if a person lost their body but retaind their heart and soul? This enemy could have been what sparked Ansem the Wise's interest in the heart. It also could be possible that one of these enemies' hearts was removed from the soul and cast into darkness, creating the first heartless, and the remaining soul being the predecessor to the nobodies.