If we assume that people on average act out of self-interest w | Golden Books™

If we assume that people on average act out of self-interest we'll be less disappointed than if we assume that people on average act out of altruism. This does not mean that we can't make things better. But doing so demands that we first understand why we are the way we are.
Richard Dawkins said in The Selfish Gene: "Be warned that if you wish, as I do, to build a society in which individuals cooperate generously and unselfishly towards a common good, you can expect little help from biological nature. Let us try to teach generosity and altruism, because we are born selfish."

Seeking Wisdom, Peter Bevelin