While I don't like to have to keep shooting down theories left and right, the Sword Logic is based completely on the idea that "If you kill a thing, you have proved to the Universe that you are stronger than it". It has nothing to do with Eris stealing the Heart of Willbreaker, and us indirectly feeding Savathûn by using the swords. At the very least, I hope that I taught OP one or two things about the Sword Logic, and that he corrects his post, so as to not misinform others.