The Judeo-Christian Worldview is based on the so-called Golden Rule ("you should treat others as you would like others to treat yourself," and its negative version and variants), which can be also found in other religious traditions, but in Christianity is regarded as an irreducible, foundational principle, since love is above all other virtues and moral values: "love others as you love yourself." If love and compassion seem to be so intuitive and universalizable among human beings of different cultural and religious backgrounds, why did it take so long for Catholics and Protestants to get along with each other, and for Western Christians to realize that slavery was wrong and that colonialism, the exploitation, and killings of African, Asian, and Native-American peoples were morally condemnable?