Abstract

Marcus Tullius Cicero (106 BC-43 BC) was the first legal philosopher in history. In Cicero’s thought we can find the Stoic conception of Natural Law, i. e., that Law is derived from God, Nature (Universe) and Human Reason. Indeed, Cicero inherits from Stoicism the Pantheistic view of Natural Law as right Reason in agreement with Nature and God (who is its author, its promulgator and its enforcing judge as well). It is a true Law of universal application, unchanging and everlasting, valid for all nations and all times. While Cicero derived many ideas on Natural Law from the Greeks, he also contributed some key ideas of his own, for instance, that whoever seeks to disobey the Natural Law flees from himself and rejects man’s nature. In other words, when man obeys the Natural Law he is obeying not only a natural and divine rule but also a rule that he gives himself as a fully rational and autonomous legislator. In this piece of research I will focus on the key aspects of Cicero’s Natural Law Theory through three masterpieces of his legal and political thought: De Re Publica, De Legibus and De Officiis, which had great influence over the medieval Christian conception of Natural Law through Lactantius (one of the Church Fathers) and Thomas Aquinas (the father of Thomism and considered the greatest theologian and philosopher of the Church).