Buddhist-inspired nonreligious philosophy is unusually honest in its understanding of human nature. There's a lot of good stuff to be found when the christian heritage of western thought is understood well enough to see it and when we, through history or creativity, walk a ways in other directions - while my first experience with this was trying to understand ancient greek morality (particularly the role of hubris in that), buddhism made a more lasting impression. I'm not sure if I owe more to Freud or to Buddhism, but both are great starts for understanding big parts of human nature - if I ever meet someone and have kids, I suspect I'd raise them based heavily around ideas extracted from those traditions.