It is a typical feature of Greek culture to conceive the lawgiver as a sort of Demiurge of the politeia. This conception fits perfectly the historical case of Cleisthenes. His radical reform of society and the Athenian political system was fully enforced in a couple of years; it was an outstanding example of a successful project of social engineering, carried on without resorting to the use of violence, and apparently lacking any philosophical foundation or justification. By contrast, there is another philosophical image of the lawgiver. In Plato, he is sometimes identified as a philosopher-king or the true ruler (Republic, Politicus), or appears to be subordinate to the kingly politician; in the Laws he may rather act as the wise advisor of a open-minded tyrant, who holds the force necessary to realize the lawgiver’s projects of social reform. These different views probably reflect in Plato’s thought the political crises and the institutional experiments of the first half of the 4th century BCE. Writing from a profoundly different conceptual frame, Aristotle draws a sharp distinction between three figures: the political philosopher, the lawgiver and the politician acting in the daily production of particular decrees (psephismata). Normally, the lawgiver should follow the philosophical indications, and in turn inspire the actual political practice, although this is not the case in a democracy ruled by assembly’s deliberations. But with Aristotle the separation between the philosophical form of life and the political one is clearly traced: the philosopher gives up any aspiration to direct rule, and restrains his task to outline the theoretical framework that may steer the actual lawgiver’s proposals.