In the Republic Plato not only uses the sets out his vision of the ideal city-state, which would be the equivalent of drawing up a utopia today, which was an organic conception segmented into three parts that we might liken to castes or classes. Plato saw the state as organic in the way that it mirrored the tripartite model of a human being – reason, spirit and desire. The ideal society would be stratified into three classes along the same lines. The workers being desire, the guardians are spirit and the ruling class are reason. Plato had a specific idea for the rulers of this utopia, it would be a ruling class made up entirely of philosophers who would be able to steer society in the right direction. The model for the ruling class in the Republic was the Spartan oligarchy (a stark contrast to the Athenian democracy) who had achieved a degree of unity through austere discipline, military training and communal living.
In order to fully understand the notion of philosopher-kings and eventually the specific qualities which qualify such thinkers to rule, it’s vital to first understand the underlying theory – the theory of Forms – as well as the simile of the cave. According to the theory the senses can only inform us of a poor copy of reality, and not what the world really is like, only through reason can the world be understood for all it is. Everything is a shadow of its Form and each horse is a lesser version of a perfect horse, such a horse exists in a world of Forms which can only be perceived through reason alone. In the cave there are prisoners who are being held in place with chains preventing them from escaping. In between them and a wall is a fire, the light of which projects shadows onto the wall. Everything from people to objects is understood by these people through these "projections" – who have been held captive here since childhood. The prisoners only really see the shadows of the world, but they think they are looking at the world as it is. When the chains are broken and one of these prisoners is liberated, the compelling light shining into the cave will initially distress him and the transition will be painful.
At first the freed prisoner will be unable to see the world as it is, because their eyes will have adjusted to the darkness of the cave, after the transition the prisoner will experience an “upward progress of the mind” and may eventually see the Form of the Good which is essential for rational thought. But an enlightened person breaking the chains of the prisoners to lead them out of the cave and into the real world might be killed by the newly freed prisoners. For the prisoners might be so embedded in the shadows of the cave that they will not want to be liberated. For this reason the prisoner, who is enlightened, may not be so willing to return to the cave especially after seeing the real world which might make him prefer to live, as Homer put it, like "a serf in the house of some landless man" than in the cave. This is the primary qualification of the philosopher to rule in the cave, the unwillingness to return to the darkness of the lower levels where the prisoners are still enthralled by shadows. A similar sentiment to all of this was later expressed by Gore Vidal "Any American who is prepared to run for President should automatically, by definition, be disqualified from ever doing so."
The philosopher is somewhat obligated to “return” to the lower levels and rule in the “cave”, regardless of their own unwillingness which is in itself a qualifying factor, because philosophers were “bred” and are “fully educated” to lead. In other words, their education and background has ensured a level of expertise and Virtue which enables them to govern in such a way as to benefit society as a whole. The Spartan oligarchs had been anti-intellectual, oppressive and militaristic. Plato thought these aspects could be avoided through such a political system which placed power in the hands of philosophers. Every citizen is a part of society and each belongs to one of the three parts of the hierarchy. No class of people, nor any particular individual, should be the focus of special treatment over the rest of society and it ought to be society as a whole that is the focus. Therefore philosophers can’t be left to live in perpetual contemplation and must lead as they have seen the Form of the Good. Though, the implications of the qualified philosopher-rulers are unsettling today as we know too well about authoritarian regimes.
It has been argued that the Republic is a philosophical precursor to forms of authoritarianism in the modern age, particularly as the philosopher-king is similar to the concept of a benign dictator. The complete absence of checks and balances on the edicts of the philosopher-kings and -queens would concern any liberal today. Karl Popper went as far as to claim that the Republic was the progenitor of 20th Century totalitarianism – even more fundamental than Nietzsche or Marx as others had claimed – from which Communism and Fascism were eventually spawned. Ironically, Karl Popper was a member of the Mont Pelerin Society alongside prominent libertarians such as Ludwig von Mises and Friedrich Hayek, both of whom were defenders of authoritarian states in Europe and Latin America along far less scrupulous grounds than Plato. In theory a ruling class consisting of philosophers would be virtuous and not oppressive. It would be beneficial to the common people, whilst maintaining an orderly hierarchy, ensuring harmony through expertise and unity. Whether or not it would turn out like that in practice is another matter, especially as philosophers are not perfect figures and could easily advocate a disastrous measure.
It’s important to note the circumstances of Plato’s life, we will assume what we know of his life is accurate of him in order to explore what influenced his philosophical opinions, especially when it comes to politics and the kind of society Plato had in mind in the Republic. Plato was an aristocrat, had he not been a philosopher he would have probably been a politician as he was related to various political figures linked through his uncle Critias and cousin Charmides to the ‘Thirty Tyrants’ who were installed through a coup supported by Sparta. The family ties to Sparta may explain Plato’s admiration for the oligarchy. As a young man he saw Athens defeated in war and may well have attributed the defeat to rise of democracy. As if Plato’s position in Athenian society was not reason enough to despise democratic principles Plato witnessed these same principles applied to condemn Socrates to death. The disposition towards a benevolent authoritarianism in his work is easily understood within this context. It is not simply the case that Plato favoured a form of oligarchy, which placed not the rich in power but those rich in knowledge in power, over democracy. Both oligarchy and democracy had failed in Athens, leading either to oppression by the ‘Thirty’ or senseless results like the death of Socrates, Plato opted for an oligarchy with a high benchmark that would exclude almost all despots.
In regards to democracy, for Plato, it is not simply that the masses will make the wrong decision because they do not truly know what they want, but a cynical resignation which creates a gap between what the people actually want and the way the people vote. Take the 2005 General Election which Tony Blair came out as Prime Minister, even though he was regularly voted the most unpopular man in Britain, New Labour won the election because there was no way for the political discontent to be effectively expressed and ultimately turned into disillusionment. There is an awareness of this in the Platonic critique of democracy, the plurality of interests given representation in a democracy and the negotiation between such private interests leaves no room for Virtue. For Plato it was a matter of privileging Virtue above such a plurality. Similar instances of this have been seen in the Republic of Virtue that the Jacobins tried to create in France as well as many socialist revolutions that have sought to replace liberal democracy with a dictatorship of the proletariat.
As Plato saw it the philosopher was qualified to rule because of an unwillingness which would prevent the power hungry from gaining power, the expertise philosophers had gained through a high standard of education and noble backgrounds would ensure a virtuous and harmonious rule in the Republic. Though this is a utopian vision, which Aristotle diverged from greatly and went on to argue that democracy was preferable to the other systems (oligarchy and aristocracy) and it would function best if inequality was eliminated. The elimination of such inequality could resolve the problems Plato saw in the plurality and negotiations of democracy which left no room for Virtue. With this in mind it might be best to advocate freeing the prisoners in the cave.
 Plato, The Republic, Melissa Lane, Introduction (Penguin, 2007) pg.29-32
 Plato, The Republic, Melissa Lane, Introduction (Penguin, 2007) pg.14-17
 The Philosophy Book, W Buckingham, D Burnham, C Hill, PJ King, J Marenbon, M Weeks (Dorling Kindersley Limited, 2011) pg. 50-55
 Plato, The Republic, Melissa Lane, Introduction (Penguin, 2007) pg.240-248
 Plato, The Republic, Melissa Lane, Introduction (Penguin, 2007) pg.13-14
 Mises served as an economist for the Fascist regime of Austria in the 1930s, providing a theory of the 1929 Crash which held state intervention responsible, and praised Mussolini “It cannot be denied that Fascism and similar movements aiming at the establishment of dictatorships are full of the best intentions and that their intervention has, for the moment, saved European civilisation. The merit that Fascism has thereby won for itself will live on eternally in history.” Richard Seymour, The Meaning of David Cameron (Zero, 2010) pg.32-35
 For example, when Maoist China developed nuclear weapons and detonated its first atomic bomb in the 1960s it was a philosopher, namely Karl Jaspers, who was quick to advocate a large-scale atomic assault on China to prevent it from becoming a threat to world peace. Slavoj Žižek, Living in the End Times (Verso, 2010) pg.10-11
 Bertrand Russell, The History of Western Philosophy (1946) pg.122-124
 Slavoj Žižek, First as Tragedy, Then as Farce (Verso, 2009) pg.136-137
 Aristotle, The Politics (Penguin, 1981) pg. 361-375