The Mahabharata opens with a boast few books could make: whatever is here may be found elsewhere, but what is not here is found nowhere. It is many times the length of the Iliad and Odyssey put together, and it holds, besides its central story, the Bhagavad Gita, hundreds of nested tales, and treatises on kingship and law.
But the reason the epic has held India for two thousand years is not its size. It is that it refuses to make goodness simple. Every character who tries to do the right thing finds it tangled with the wrong, and the epic does not look away from the tangle.
Vyasa and the scale of the epic
Tradition attributes the Mahabharata to the sage Vyasa, Krishna Dvaipayana, who also arranged the Vedas. He is also a character inside his own story, the grandfather by blood of both sides of the war.
The epic is traditionally reckoned at a hundred thousand verses in eighteen books (parvas). Scholars believe it grew over several centuries, perhaps from around 400 BCE to 400 CE. It calls itself itihasa, "thus indeed it was": history, in the sense of a story the tradition holds true at the level that matters.
The story in brief
Two branches of the Kuru family contest the throne of Hastinapura. The blind king Dhritarashtra has a hundred sons, the Kauravas, led by the ambitious Duryodhana. His brother Pandu has five, the Pandavas, each fathered by a god through a mantra given to their mother Kunti: Yudhishthira by Dharma, Bhima by Vayu the wind, Arjuna by Indra, and the twins Nakula and Sahadeva by the Ashvins through Pandu's second wife Madri. Before her marriage Kunti had also borne a son to the sun god, Karna, whom she set adrift; raised by a charioteer, he became the Pandavas' greatest enemy without knowing he was their brother.
The cousins are trained together by Drona and grow up rivals. After an attempt on the Pandavas' lives the kingdom is divided. The Pandavas marry Draupadi, won by Arjuna at her swayamvara, and build the city of Indraprastha, whose splendour fills Duryodhana with envy.
Duryodhana's uncle Shakuni turns the envy into a plan: invite Yudhishthira to a game of dice. Yudhishthira, who will not refuse a challenge, loses his wealth, his kingdom, his brothers, himself, and finally Draupadi. She is dragged into the assembly and the Kauravas try to strip her, and she asks the question that hangs over the rest of the epic: if Yudhishthira had already lost himself, what right had he to stake her? No elder answers. Bhishma says only that dharma is subtle. The Pandavas go into exile for twelve years, with a thirteenth to be spent in disguise.
When they return, Duryodhana refuses to give back even five villages. Krishna, the Pandavas' cousin and ally, goes as an envoy and fails. The war at Kurukshetra lasts eighteen days and consumes nearly every warrior on both sides. Bhishma, Drona, Karna and Duryodhana fall in turn, each by a means that bends the rules of war. The Pandavas win, and inherit a graveyard.
The Gita within it
On the first morning Arjuna asks Krishna, his charioteer, to drive between the armies, and seeing his teachers and kinsmen on the other side he drops his bow. The Bhagavad Gita is the conversation that follows: eighteen chapters, about seven hundred verses, in which Krishna leads Arjuna from despair to clarity through the paths of action, knowledge and devotion. It is spoken not in a hermitage but on a battlefield, to a man who must act and cannot see how.
You have a right to your actions alone, never to their fruits. Let the fruits of action not be your motive, nor let your attachment be to inaction.
Three lives, three dilemmas
Yudhishthira
Yudhishthira is called Dharmaraja, king of righteousness, and the epic tests him more severely than anyone. On the battlefield he, who has never lied, is persuaded by Krishna to tell Drona that Ashvatthama is dead, adding under his breath that he means an elephant of that name; Drona, trusting him, lays down his arms and is killed. Yudhishthira's chariot, which had always floated a hand's breadth above the ground, sinks to the earth. At the very end, climbing into the Himalayas, he refuses to enter heaven without the stray dog that has followed him, and the dog reveals himself as Dharma, his father.
Bhishma
Bhishma was born Devavrata, heir to Hastinapura. When his father wished to marry the fisherwoman Satyavati and her father demanded that her sons inherit, Devavrata gave up the throne and then swore lifelong celibacy. The gods named him Bhishma, "the terrible", for the vow, and his father granted him the power to choose the hour of his death.
The vow made him the most honourable man in the epic and also its most helpless. Bound to serve whoever sat on the throne, he fought for Duryodhana, whom he knew to be wrong. He sat silent while Draupadi was shamed. He died on a bed of arrows, waiting for the auspicious half of the year, teaching Yudhishthira the dharma of kings. The epic lets us admire him and lets Draupadi's question stand unanswered beside him.
Karna
Karna, the abandoned son of the sun, was mocked all his life for his charioteer's birth. When he was refused a place at the princes' tournament, Duryodhana made him a king on the spot, and from that moment Karna's loyalty was absolute. Before the war Krishna tells him the truth of his birth and offers him the throne as the eldest Pandava; Kunti herself comes to him. He refuses them both, promising his mother only that he will spare four of her sons and fight Arjuna alone, so that she will still have five at the end. He dies when his chariot wheel sticks in the mud and Arjuna, on Krishna's urging, shoots him as he struggles to free it. Karna is the epic's proof that a person can be brave and faithful and still be on the wrong side, and that the wrong side is sometimes the price of gratitude.
The Yaksha's questions
During the exile the brothers come one by one to a lake to drink and are warned by a voice to answer its questions first. Each ignores it and falls dead. Yudhishthira, arriving last, stops and answers. The questioner is a yaksha, a nature spirit. What is heavier than the earth? A mother. What is faster than the wind? The mind. What is the path? Reasoning has no end, the scriptures differ, no sage's word is final, and the truth of dharma lies hidden in a cave; the path is the one the great have walked. And what is the greatest wonder? That every day creatures depart for the house of Death, and those who remain believe they will live for ever.
The yaksha offers to revive one brother. Yudhishthira chooses Nakula rather than one of his own full brothers, so that each of his father's two wives will have a son left alive. The yaksha, who is Dharma in disguise, revives them all.
Why no easy answers, and where to begin
The Mahabharata does not teach that dharma is unknowable. It teaches that dharma is subtle, that circumstances change it, and that the person who claims always to know it has stopped looking. Vyasa ends with a cry of despair: with arms raised he calls out that wealth and pleasure both flow from dharma, so why is dharma not followed, and no one listens. That the question is still being asked is the epic's answer.
Begin with the Yaksha Prashna in the forest book, which is short and complete in itself. Then the dice game, then the Gita with a commentary you trust. Only then take on the whole, and take it slowly; it was never meant to be finished in a week.