Principle of double effect
The principle of double effect or doctrine of double effect is an idea in philosophy.  It says that it can be morally good to do something that has a bad effect so long as it also has a larger good effect.  Here, "double effect" means "second effect" or "side effect." In plain English, the principle of double effect means, "It is acceptable for actions to have bad side effects so long as the good effect is much larger."