Human nature and political legitimacy

From ancient times, and well beyond them, the roots of justification for political authority were inescapably tied to outlooks on human nature. In The Republic, Plato declared that the ideal society would be run by a council of philosopher-kings, since those best at philosophy are best able to realize the good. Even Plato, however, required philosophers to make their way in the world for many years before beginning their rule at the age of fifty. For Aristotle, humans are political animals (i.e. social animals), and governments are set up in order to pursue good for the community. Aristotle reasoned that, since the state (polis) was the highest form of community, it has the purpose of pursuing the highest good. Aristotle viewed political power to be the result of natural inequalities in skill and virtue. Because of these differences, he favored an aristocracy of the able and virtuous. For Aristotle, the person cannot be complete unless he or she lives in a community. His two books, The Nicomachean Ethics and The Politics, are meant to be read in that order. The first book addresses virtues/excellences in the person as a citizen; the second addresses the proper form of government to ensure virtuous (and thus complete) citizens. Both books deal with the essential role of justice as a necessary virtue in civic life.

Nicolas of Cusa rekindled Platonic thought in the early 15th Century and promoted democracy in Medieval Europe in his writings and his organization of the Council of Florence. Unlike Aristotle and the Hobbsenian tradition to follow, Cusa saw man as equal and divine (in God's image) and thus democracy would be the only just form of government. Cusa's views are credited by some as sparking the Italian Renaissance which gave rise to the notion of "Nation-States".

Later, Niccolò Machiavelli, rejected Aristotle's (and Thomas Aquinas') view as unrealistic. The ideal sovereign is not the embodiment of the moral virtues; rather the sovereign does what's successful and necessary rather than what's morally praiseworthy. Thomas Hobbes also contested many elements of Aristotle's views. For Hobbes, human nature is essentially anti-social: people are essentially egoistic, and this egoism makes life difficult in the natural state of things. Moreover, Hobbes argued, though people may have natural inequalities, these are trivial, since no particular talents or virtues that a person may have will make them safe from harm inflicted by others. For these reasons, Hobbes concluded that the state arises from common agreement to raise the community out of the state of nature. This can only be done by the establishment of a sovereign, which (or who) is vested with complete control over the community, and is able to inspire awe and terror in its subjects.

Many in the Enlightenment were unsatisfied with existing doctrines in political philosophy, which seemed to marginalize or neglect the possibility of a democratic state. One attempt to overturn these doctrines was that of Jean-Jacques Rousseau, who responded to Hobbes by claiming that a human is by nature a kind of "noble savage", and that society and social contracts corrupt this nature. In his Second Treatise on Government John Locke agreed with Hobbes that the nation-state was an efficient tool for raising humanity out of a deplorable state, but argued that the sovereign may become an abominable institution compared to the relatively benign unmodulated state of nature.

Following the doctrine of the fact-value distinction, due in part to the influence of David Hume and his student, Adam Smith, appeals to human nature for political justification were weakened. Nevertheless, many political philosophers, especially moral realists, still make use of some essential human nature as a basis for their arguments.