One of the central challenges confronting post-colonial India in its march towards decolonisation was the intellectual challenge posed by the idea of modernity. This is reflected in the work of historians of science and philosophers attempting to understand what the past of ‘Indian science’ or ‘Indian philosophy’ meant in relation to the identity of the modern Indian nation state in the making. This essay argues that in this interrogation there were common themes that were entangled in the enterprise of historians of science and philosophers. Beyond the question of the identity of Indian philosophy or Indian science was the attempt to locate the place of reason and science, and in the spirit of modernisation theory to trace the causes of their ascent or decline at the centre of Indian culture over historical time. The paper examines the entanglement of these two discourses and situates them during the decades of decolonisation