But, we do know that darkness is born from evil. In the beginning, when everything was light, darkness came from greed. While being greedy does not equate to being evil, greed in and of itself is undoubtedly an evil thing. Greed is selfish, and as we've seen over and over again throughout KH, being selfless and helping others is what ultimately wins in the end.
So, no, darkness does not automatically make a person evil. But, complete darkness, given that darkness is born only from bad, would be evil. However, that was my whole point with why MX isn't pure darkness.
Being greedy does not equate to evil. It's a fast track to it yes but that still doesn't make MX less evil just because he isn't pure darkness or Vanitas evil by default because he is.
Darkness feeds on negativity not evil itself. Shown by even beings of pure light like Cinderella who expressed emotions of sadness and maybe even depression drawing the embodiments of negativity, Unversed, right to her.
And if a being lacking any darkness can show negativity that means a being lacking light should be able to show the opposite.
Point being Vanitas was created from Ventus by MX, trained by MX, all his time was spent either with MX, fighting Ven or Aqua.
Vanitas didn't have a chance to show anything otherwise than the evil he was exposed to by Xehanort.
And look at the list of things done by Vanitas compared to Xehanort. Can you honestly still say Vanitas is more evil than MX simply because of what he is?
No. It's the circumstances of his life that make him how he is
in conjunction with darkness' appetite to feed on negativity.
Not that I disagree that MX isn't pure evil although I find it highly impossible any good still remains in him at this point, but my point is that just cause he's not pure dark doesn't equate that he's not pure evil.
This is also shown in the fact that everything is a mix of light and dark with the exception of 9 people, only 7 of which is natural.
The only possible way MX could ever be pure darkness is if he ripped the light out of himself the same way he took the darkness from Ventus because that's the only other way for pure hearted beings to exist in the KH universe.
So no just cause MX isn't pure darkness doesn't mean he is pure or next to pure evil.
Darkness is tied to the negativity but I think we've already seen plenty of reasons, in cases listed as well as with Riku and Eraqus, why it's not as simple as "darkness equals evil" or dictates the level of that evil.
It's far more complex than that.
EDIT:
The best example of what I mean is Terra. He's far from evil but still has a strong affinity for darkness and has since before MX meet him. In fact it was his affinity to darkness that gave MX the idea to target him to start with.
Nothing Terra did in the story was evil and what he was tricked into doing was unknowing on his part so he had no evil intent.
The only time Terra expressed something to feed his darkness was the hatred he developed for Xehanort which finally set his darkness loose but even then Terra didn't lose himself, just made himself open to MX's possession.
