Ghosts in the algorithm India's financial system has digitised its ledgers but not its prejudices. A millennium-old caste hierarchy is proving remarkably adept at corrupting the code designed to replace it. Nagesh Bhushan Microfinance was once sold as a revolution. Its evangelists promised precision-targeted capital delivered to the "bottom of the pyramid" — a phrase that, in the optimism of the 2000s, seemed to imply the pyramid might eventually be flattened. A generation later, the pyramid stands largely intact. India has digitised its banking infrastructure with genuine speed and ambition. What it has not managed to digitise away is caste. The persistence of caste-based financial exclusion in an era of algorithmic lending is not merely an irony. It is an indictment — of institutions that have adopted the aesthetics of modernity while preserving its oldest hierarchies, of regulators who have measured financial inclusion by the number of accounts opened rather than the...