According to Pennington, the terms Hindu and Hinduism were thus constructed for colonial studies of India. The various sub-divisions and separation of subgroup terms were assumed to be result of "communal conflict", and Hindu was constructed by these orientalists to imply people who adhered to "ancient default oppressive religious substratum of India", states Pennington. Followers of other Indian religions so identified were later referred Buddhists, Sikhs or Jains and distinguished from Hindus, in an antagonistic two-dimensional manner, with Hindus and Hinduism stereotyped as irrational traditional and others as rational reform religions. However, these mid-19th-century reports offered no indication of doctrinal or ritual differences between Hindu and Buddhist, or other newly constructed religious identities. These colonial studies, states Pennigton, "puzzled endlessly about the Hindus and intensely scrutinized them, but did not interrogate and avoided reporting the practices and religion of Mughal and Arabs in South Asia", and often relied on Muslim scholars to characterise Hindus.