It’s not only the intent behind attempted murder, but the successful execution of that intention:
“But how do you [create a Horcrux]?”
“By an act of evil — the supreme act of evil. By committing murder. Killing rips the soul apart. The wizard intent upon creating a Horcrux would use the damage to his advantage: He would encase the torn portion —” (HBP Ch 23)
It’s possible that Snape’s soul did split. When Snape and Dumbledore are discussing the plot to have Dumbledore killed, there’s this exchange:
“If you don’t mind dying,” said Snape roughly, “why not let Draco do it?”
“That boy’s soul is not yet so damaged,” said Dumbledore. “I would not have it ripped apart on my account.
“And my soul, Dumbledore? Mine?”
“You alone know whether it will harm your soul to help an old man avoid pain and humiliation.” (DH Ch 33)
“You alone know whether it will harm your soul to help an old man avoid pain and humiliation.” (DH Ch 33)
That’s exactly the point—whether an act is a “murder” or a “mercy” depends on the intent of the person performing the act. Murder splits the soul, mercy doesn’t. And only Snape alone knows which one he would do.
You’re right. I was thinking in terms of the difference between murder and attempted murder, when the important difference here is between murderous killing and non-murderous killing.
It still seems true that one’s soul will only split in the case of successful murder.
edited in response to the below
It’s not only the intent behind attempted murder, but the successful execution of that intention:
It’s possible that Snape’s soul did split. When Snape and Dumbledore are discussing the plot to have Dumbledore killed, there’s this exchange:
That’s exactly the point—whether an act is a “murder” or a “mercy” depends on the intent of the person performing the act. Murder splits the soul, mercy doesn’t. And only Snape alone knows which one he would do.
You’re right. I was thinking in terms of the difference between murder and attempted murder, when the important difference here is between murderous killing and non-murderous killing.
It still seems true that one’s soul will only split in the case of successful murder.