The philosopher king is a concept that comes to us from Plato.
In the Republic, book V, 473d, Plato insists that philosophy and kingship must coincide. Otherwise, the kingdom will always be subject to troubles.
Thus Plato writes:
“Unless, I say, philosophers succeed in ruling in the cities, or unless those who at present are called kings and dynasts philosophize authentically and satisfactorily and the one with the other political power and philosophy coincide; unless the numerous naturals of those who at present turn separately to one or the other are forcibly prevented from doing so, there will be no end to the evils of the cities nor, it seems to me, to those of the human race”.
In the context of the Sciences Po exam on Revolutions, it is then possible to ask whether in the case where royalty and philosophy coincide as Plato wishes, Revolutions would cease to be necessary, and therefore disappear.