So it's "all or nothing", rather than the "one step at a time" philosophy?
I have stopped people breaking into someone's car, because I was passing at the time - but I don't drive around looking for crimes to prevent; according to you, I shouldn't have intervened, since I am not prepared to stop all crime.
Further to that, why should doctors and hospitals help sick people - they are all going to die in the end (this is just an example to show how using extremes doesn't really validate propositions

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