Would I give up my entire physical and psychological wellbeing, getting myself tortured to save the world? No, I would not.
Was raised with the idea that that was the highest any person could do, the example of Jesus doing that being crucified.
And following Jesus was the best anyone could do.
Had you asked me this question 30 years ago, I would have said that I would.
But no, I will not voluntarily let myself get tortured for the world.
Don't believe it will do anyone any good. And it is too vague a target anyway. Saving the world.
Yet, I cannot say that I will never do something, regardless of the harm it could do me, to better something.
Not that I am a saint. But sometimes, you have to do something. And nothing can stop you. No reason, no friends on the sideline. It just has to be done, there and then. It could be racing in the street to grab a child away from an oncoming car, while getting damaged forever. Or anything else. Sometimes, people act an 'irresponsible' act of goodness, without any thought of reward or danger, because they just have to. Mostly it is about very specific things. Not something general as saving humankind.
I do believe in those acts of goodness. They just happen. Somewhere ingrained in humanity. Just like the capability to torture is ingrained. Hope I'll never do that. But I'm not that optimistic about humans that I dare to deny the possibility.