The Arthashastra is an “important Indian manual on the art of politics (EB).” It identifies its author by the name “Kauṭilya,” among others (Wikipedia).
As I read about it, I immediately thought of Machiavelli’s book The Prince, which for Westerners is the standard guide to political ruthlessness. Apparently, though, Machiavelli is a bit tame. According to Wikipedia:
Because of its harsh political pragmatism, the Arthashastra has often been compared to Machiavelli’s The Prince.
Is there any other book that talks so openly about when using violence is justified? When assassinating an enemy is useful? When killing domestic opponents is wise? How one uses secret agents? When one needs to sacrifice one’s own secret agent? How the king can use women and children as spies and even assassins? When a nation should violate a treaty and invade its neighbor? Kautilya — and to my knowledge only Kautilya — addresses all those questions. In what cases must a king spy on his own people? How should a king test his ministers, even his own family members, to see if they are worthy of trust? When must a king kill a prince, his own son, who is heir to the throne? How does one protect a king from poison? What precautions must a king take against assassination by one’s own wife? When is it appropriate to arrest a troublemaker on suspicion alone? When is torture justified? At some point, every reader wonders: Is there not one question that Kautilya found immoral, too terrible to ask in a book? No, not one. And this is what brings a frightful chill. But this is also why Kautilya was the first great, unrelenting political realist.
—Boesche (2002, p. 1)
Max Weber observed:
Truly radical ‘Machiavellianism’, in the popular sense of that word, is classically expressed in Indian literature in the Arthasastra of Kautilya (written long before the birth of Christ, ostensibly in the time of Chandragupta): compared to it, Machiavelli’s The Prince is harmless.
—Max Weber, Politics as a Vocation (1919)
However, these aspects form just one of the 15 books that comprise the Arthaśāstra. The scope of the work is far broader than popular perceptions indicate, and in the treatise can also be found compassion for the poor, for servants and slaves, and for women. For instance, Kautilya advocates what is now known as land reform, and elsewhere ensures the protection of the chastity of female servants or prisoners. Significant portions of the book also cover the role of dharma, welfare of a kingdom’s subjects and alleviating hardship in times of disaster, such as famine.
It would be interesting to read Arthashastra‘s advice on torture and compare it with current arguments in the age of terrorism.