Altruism is the prevailing morality throughout the world. But what explains its philosophical persuasiveness? Although it cannot be practiced consistently, the doctrine that self-sacrifice is good and self-interest evil, is accepted as true by virtually everyone. Yet no argument—even a semi-plausible one—is ever offered to justify the status of man as a sacrificial animal. Why then is it so difficult to convince people of the baselessness of this doctrine? This talk examines the means by which the proponents of altruism present their case—and discusses what the proponents of egoism need to do to change our altruistic culture.