Final answer:
The paradox referred to by Salman Rushdie is 'unity in diversity', encompassing the conflicting notions of diverse cultural coexistence and the nationalist push for homogeneity through Hindutva.
Step-by-step explanation:
The paradox about Indian nationalism that occurs to Salman Rushdie as he talks to Robi Chatterjee is the idea of unity in diversity. Rushdie's discussion highlights the complexity of Indian nationalism, which contends with reconciling the country's vast ethnic, linguistic, and religious pluralism with the political drive for a unified national identity. The tension echoes in the paradoxical coexistence of India's inherent diversity with the nationalist aspiration for unity, bringing forth a debate about whether true unity in a country like India can ever disregard its multiplicity.