All that is solid melts into air
The city of Calcutta was a concrete manifestation of a social revolution in India that took place in the eighteenth and nineteenth centuries. A revolution where the institution of caste-based occupation melted into thin air. Brahmins became merchants and merchants became scholars. The Sinha family is a good example. After making money from trading in textiles, they became zamindars or landlords and then part of the professional class; the most prominent of the of them, Lord Sinha, entered politics towards the end of his career, and all this happened within three generations. [1]
This kind of occupational mobility was unthinkable in the 1780s but was quite normal by 1850 — not everywhere in British India; the village life continued pretty much unchanged but in Calcutta, the old norms were swept away
[1] See N K Bose, 1949, ‘The Structure of Hindu Society’ https://archive.org/details/in.ernet.dli.2015.142550