Philosophy
The Doctrine of Double Effect in Justifying Actions
Quick fact
The Doctrine of Double Effect was famously developed by Thomas Aquinas in the 13th century to explain how killing in self-defense could be permissible: the defender intends to save their own life, while the attacker's death is merely foreseen, not intended.
Why this is interesting
You already know it's wrong to deliberately harm someone. But is it just as wrong to do something good while foreseeing that harm will come along with it?