Why did he burn the Manusmriti, and what is in it?
The Manusmriti is an ancient Sanskrit text of religious law — one of the works that set out dharma, the duties proper to each person. What made it the target was its content: it codifies the fourfold order of caste, assigns duties and punishments by rank, places the Shudra at the bottom of the four, and prescribes a subordinate station for women. Where a modern reader sees a historical document, the orthodoxy of Ambedkar's day treated it as an authority for how society ought still to be arranged.
On 25 December 1927, during the conference at Mahad, he and his colleagues publicly burned a copy of it. The act was deliberately symbolic and it was aimed at a single thing: the claim that caste rests on scriptural sanction. He was not asserting that one book had caused untouchability, nor calling for the burning of books as a habit; he was staging, in the most visible way available, the argument that graded inequality was written into the tradition's own texts and that reform therefore had to confront those texts rather than tiptoe around them.
Set beside the rest of the Mahad conference — where the assertion was the right to drink from a public tank — the burning completes a single gesture. One half claimed a concrete right the village denied; the other half struck at the scriptural authority the village invoked to deny it. It remains one of the most quoted and most argued-over acts of his career, precisely because it went at the sacred sanction rather than only the social practice.