What is dharma in the Mahabharata?

Dharma covers ground that no single English word does. It is the order that holds the world together; it is the law a king enforces; it is the duty attached to a station, a caste, a stage of life; and it is what this person ought to do now. The epic uses all these senses and plays them against each other.

The whole poem is an argument about it. Bhishma keeps an oath and by keeping it destroys the dynasty he swore to protect. Yudhishthira, called the son of Dharma, gambles away his wife. Arjuna refuses to fight his teachers and is told that refusing is the greater failure. Krishna advises deceptions at almost every critical moment of the war: the half-truth that kills Drona, the reminder of broken rules that kills Karna, the signal that guides Bhima to break Duryodhana thighs. Karna is generous and loyal and stands with the side that strips a queen in public.

The epic supplies formulas and then tests them. Dharma protects those who protect it, it says; Bhishma protected dharma as he understood it and was not protected. Where dharma is, there is victory: the phrase is repeated before the war by people who are about to lose, and by people whose victory will be indistinguishable from ruin. Non-violence is the highest dharma, and this is said inside a poem about a war.

Two working ideas recur. The first is svadharma, the duty proper to you rather than the one that looks nobler: it is better to do your own duty badly than another duty well. The second is apad-dharma, the law for emergencies, which accepts that in extremity the ordinary rules bend, and which the epic uses to explain and to worry about almost every act of cleverness in the war.

The most quoted admission in the whole text is Bhishma answer under pressure: the path of dharma is subtle, and even the wise are confused about it.