The right of asylum, sometimes called right of political asylum (asylum from Ancient Greek ἄσυλον (ásulon) 'sanctuary'), is an ancient juridical concept, under which people persecuted by their own rulers might be protected by another sovereign authority, such as a second country or another entity which in medieval times could offer sanctuary. This right was recognized by the Ancient Egyptians, the Greeks, and the Hebrews, from whom it was adopted into Western tradition. René Descartes fled to the Netherlands, Voltaire to England, and Thomas Hobbes to France, because each state offered protection to persecuted foreigners. Contemporary right of asylum is founded on the Universal Declaration of Human Rights.