For humans, the idea that we would do labor or give up resources without direct benefit requires having faith that the universe will attend to our generosity. Our culture of winning, getting ahead, and zero-sum gains does not support this kind of mind-set. It’s more than the idea of self-sacrifice as a practice you benefit from because it makes you feel righteous or earns you points with your god. It’s also about recognizing that our collective survival depends on understanding that there is enough for all of us and we don’t need to hoard resources at the expense of others