For clarity, I will ask the "same" question several different ways:
Is it wrong to have bad thoughts?
Does having and enjoying evil thoughts make one evil?
Is having bad thoughts wrong, even if no action is intended?
Is it wrong to wish harm to another person?
Mainly, if merely having bad thoughts is wrong, why EXACTLY is it wrong?
A version of this question has been asked here before, but I feel the answer did not address the essence or why having bad thoughts is wrong.
(What I'd really like to know is what philosophical principle addresses this question, so that I can look into it much further than this small space can provide.)
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