Kautilya lived in India from 375 to 283 BC. He ranks alongside Sun Tzu as one of the great early sages who wrote about the relations between polities, and thus also about wars between them. Kaushik Roy, Guru Nanak Chair Professor at Jadavpur University, India, joins Beatrice and Paul to discuss his work.

Kautilya's approach to strategy included an understanding of inter-polity relations that assumed that one's 'enemy's rear-enemy' would be a good ally against the shared enemy: in other words, 'make friends with your enemy's enemy'. Meanwhile, insurgents would get support from other polities, and aggressors could be just, or just greedy. He thus paired 'realist' views with moral elements.

Also referred to as Chanakya or Vishnugupta, Kautilya was adviser to two successive emperors of the Mauryan Empire in India. He was thus not only a theoretician but also had considerable political influence. His main body of work is the Arthashastra, an ancient Sanskrit treatise on statecraft, political science, economic policy and military strategy. While one is hard-pushed to argue that he had a lasting influence on the following millennia of political or strategic thinking in India, his views are worth pondering, as they cast fresh light on strategy and on relations between states.

Kaushik Roy is Guru Nanak Chair Professor in the Department of History, Jadavpur University, Kolkata, India and a Global Fellow at the Peace Research Institute Oslo (PRIO), Norway. He obtained his PhD from the Centre for Historical Studies, School of Social Sciences, Jawaharlal Nehru University, New Delhi.