Tyrannicide

Tyrannicide is the killing or assassination of a tyrant or unjust ruler, usually for the common good, and usually by one of the tyrant's subjects.

The term also denotes those who kill a tyrant (e.g., Harmodius and Aristogeiton, who are called 'the tyrannicides').

Tyrannicide can also be a political theory, and as such dates from antiquity. Support for tyrannicide can be found in Plutarch's Lives, Cicero's De Officiis, and Seneca's Hercules Furens.Plato describes a violent tyrant as the opposite of a good and "true king" in the Statesman, and while Aristotle in the Politics sees it as opposed to all other beneficial forms of government, he also described tyrannicide mainly as an act by those wishing to gain personally from the tyrant's death, while those who act without hope of personal gain and only to make a name for themselves are rare.

Various Christian philosophers and theologians also wrote about tyrannicide. In Thomas Aquinas's commentary on the Sentences of Peter Lombard, Aquinas gave a defense not only of disobedience to an unjust authority, using as an example Christian martyrs in the Roman Empire, but also of "one who liberates his country by killing a tyrant." The Monarchomachs in particular developed a theory of tyrannicide, with Juan de Mariana describing their views in the 1598 work De rege et regis institutione, in which he wrote, "[B]oth the philosophers and theologians agree, that the prince who seizes the state with force and arms, and with no legal right, no public, civic approval, may be killed by anyone and deprived of his life..."

The Jesuistic casuistry developed a similar theory, criticized by Blaise Pascal in the Provincial Letters. Before them, the scholastic philosopher John of Salisbury also legitimised tyrannicide, under specific conditions, in the Policraticus, circa 1159. His theory was derived from his idea of the state as a political organism in which all the members cooperate actively in the realization of the common utility and justice. He held that when the ruler of this body politic behaves tyrannically, failing to perform his characteristic responsibilities, the other limbs and organs are bound by their duty to the public welfare and God to correct and, ultimately, to slay the tyrant.

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