AS: your idea of equality is inherently contradictory. If all lives are equal, but as a result of saving one life I also save several others, then I should prefer to save that one life (in this moment) to saving the life of someone who won't end up saving several others. You just can't get a coherent system that behaves the way you want.
If it bothers you, just imagine that the choice isn't between saving person A and person B, the choice is between saving (A and C and D and E and F) and saving B.
If it bothers you, just imagine that the choice isn't between saving person A and person B, the choice is between saving (A and C and D and E and F) and saving B.
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