Humans hardly ever learn from the experience of others. They learn - when they do, which isn't often - on their own, the hard way.
Robert A. HeinleinThe basic of all morality is duty, a concept with the same relation to group that self-interest has to individual.
Robert A. HeinleinOf all the nonsense that twists the world, the concept of 'altruism' is the worst. People do what they want to, every time. If it pains them to make a choice - if the choice looks like a 'sacrifice' - you can be sure that it is no nobler than the discomfort caused by greediness... the necessity of deciding between two things you want when you can't have both.
Robert A. Heinlein