In the third chapter, Mill asks what "sanctions" (that is, rewards and punishments) undergird the obligation to promote the general happiness. He explores a variety of ways in which both external and internal sanctions – that is, the incentives provided by others and the inner feelings of sympathy and conscience – encourage people to think about how their actions affect the happiness of others. The ultimate sanction, Mill claims, is internal. Humans are social animals who naturally desire "to be in unity with our fellow creatures."  To prefer selfish goals over the public good runs counter to this deep-seated natural impulse.
Negative Utilitarianism requires us to promote the least amount of evil or harm, or to prevent the greatest amount of suffering, for the greatest number (as opposed to the general, or positive, Utilitiarian rule of the greatest amount of good for the greatest number). The justification for Negative Utilitarianism is that the greatest harms are more consequential than the greatest goods, and so should have more influence on moral decision-making. Critics have argued that the ultimate aim of Negative Utilitarianism would therefore logically be to engender the quickest and least painful method of killing the entirety of humanity , as this would effectively minimize suffering , although more moderate proponents would obviously not propose that.
Many philosophers believe that morality consists of following precisely defined rules of conduct, such as "don't kill," or "don't steal." Presumably, I must learn these rules, and then make sure each of my actions live up to the rules. Virtue ethics , however, places less emphasis on learning rules, and instead stresses the importance of developing good habits of character , such as benevolence (see moral character ). Once I've acquired benevolence, for example, I will then habitually act in a benevolent manner. Historically, virtue theory is one of the oldest normative traditions in Western philosophy, having its roots in ancient Greek civilization. Plato emphasized four virtues in particular, which were later called cardinal virtues : wisdom, courage, temperance and justice. Other important virtues are fortitude, generosity, self-respect, good temper, and sincerity. In addition to advocating good habits of character, virtue theorists hold that we should avoid acquiring bad character traits, or vices , such as cowardice, insensibility, injustice, and vanity. Virtue theory emphasizes moral education since virtuous character traits are developed in one's youth. Adults, therefore, are responsible for instilling virtues in the young.