A rough guideline for me is to help advance humanity on its path of technical progress (because the life I love is because of technological progress); to help those living in poverty around the world (because after I die, chances of me being born into a poor third-world country are too high); and to reduce the threat of global warming (because after I die, I want to be born again and not be un-existent in a timeless void because our planet is trashed).

My reasons are selfish unfortunately. I'm also not extremely motivated to make a personal impact on my own, so I aim to earn a high salary so I can donate to people who know what they're doing.