Hans Kelsen is one of the most important jurists of the 20th century. His work means and represents an effort to change Law into a science, which implies a defined object of study external to any interference from the justice, the moral, the political and the economic matters. Kelsen's human and intellectual efforts led him to create a system in which the legal order was a legal expression and a way to understand the social order. As a consequence, his work became a "system" upon which law and politics share an equal essence. Both in politics and in law Hans Kelsen took the theoretical reflection to unimagined and unusual edges among thinkers of that time.