The author of the paper tries to identify the basic methodological assumptions of the personal pattern of the ideal ruler as presented by Machiavelli in his Il Principe. While comparing the “mirror of the Principe” elaborated by Machiavelli, with the Galileo’s pendulum that came to being 100 years later, one may observe significant similarity between the manures along which the two devices were construed. They both came to being as a result of some idealization. Both speculum and pendulum is exploited above all in order to demonstrate interrelations between major variables which determine the course followed by the phenomena which arouse interest of both authors. In case of Machiavelli, this is the wish to describe the mechanism that is responsible for the effective – i.e. the one that guarantees the political success – method of ruling. At the same time the selection of the procedure applied for idealization (the one that requires the considering of extreme cases or disregarding the less important ones) causes that the description of the Prince assumes mainly the theoretical and ostentatious values. Thanks to the outlined analogy between pendulum and speculum it is possible to present a hypothesis that the assessment of the factual political radicalism of the methods of controlling the state as proposed in Il Principe should take into consideration not only that content of these methods which pertains to their subject matter but also the methodological nature of the entire concept.