Harvard professor Diana Eck is dumbfounded. She happens to be visiting one of India’s states that prohibit the consumption and sale of beef. “It’s astonishing that a government would pass that kind of law about what people eat,” she says at a meeting held at the Royal Bombay Yacht Club in Mumbai. “Especially in a nation as pluralistic as India... some people are vegetarian, some are non-vegetarian. I mean, this is not an area of personal life that government should be intruding on.”

Her students, she says, brush off the new laws as something that won’t really be implemented in earnestness. Is that true, she wants to know.

In town to deliver a lecture, Eck — a global authority on religion and the author of books on Banaras, India’s rivers and its geographies — is no stranger to India. She first visited the country in the 1960s and has since returned several times, including a visit in 2013 to lead a study tour of the Kumbh Mela.

The Professor of Comparative Religion and Indian Studies refuses to be drawn into discussing the usefulness of the uniform civil code [“I’m going to leave it to all of you for now,” she laughs] or whether the air has become more polarised [“I don’t sense this, but I’ve heard this”]. But she is happy to discuss threadbare what it means to be secular, particularly in India, where the term refers to an equal treatment of all religions, rather than the western conception of religion as separate from the State. So, is that under threat?

“It may be,” she says. “People do say that.” She continues, “I think with a government that has many of its followers saying that all Indians are originally Hindu in the broadest possible way, that does place secularism under threat. Secularism isn’t non-religion because India is a very religious country in so many ways. But secularism as the equal treatment of all religions… that’s very important.”

Eck has previously received the National Humanities Medal in the US and served as president of the American Academy of Religion. She has also, since 1991, led the Pluralism Project, an initiative aimed at understanding her country’s burgeoning diversity. “And that expanding diversity is very good for a country of immigrants (except for the native people, who are themselves diverse),” she says. “The US is a newly and profoundly diverse nation in ways we notice more than in India.”

But it’s a diversity that’s increasingly under attack from the Right, led in no small measure by presidential aspirant Donald Trump. “This is just absurd, the idea that someone harks back to nativist rhetoric,” she says.

She is not entirely surprised when the topic of ‘ghar wapsi’ and the reconversion-to-Hinduism debate is raised. “It’s not entirely new,” she says, pointing to similar episodes in the 1920s and the tensions as a result within the Indian freedom movement. On whether the State should have a role to play in this sort of thing, she is categorical, “The government really shouldn’t have a role in who should convert or reconvert… The real issue is how much coercion is levied.”

Scheduled to later deliver the Vasant J Sheth Memorial lecture on India’s sacred rivers, Eck, who has closely studied Banaras, says she found the city’s Assi Ghat “better than ever” on her current visit. “There is certainly an effort to underline the message [of the countrywide Swachh Bharat cleanliness movement],” she says. “The message is itself important. It can become too much of a slogan, I imagine; so it needs to have something behind it.”

Cleaning up the Ganga is not a new idea. Thirty years ago, one of Eck’s teachers launched an initiative to do just this. It is inexplicable why rivers — one of Eck’s areas of expertise — are so poorly looked after and massively polluted despite being considered sacred. “I think people, here and elsewhere, have a divided consciousness,” she says. “‘Yes, it’s a sacred river, [but] no, its sacredness does not diminish because we pollute it’.”

During her lecture, she is careful to emphasise that rivers need to be understood and approached holistically.

“You need people on both sides,” she says, meaning those who are scientifically astute as well as those who can understand the sanctity of the river and the significance it holds. “We need to balance the need for dams and hydro-electric power projects, canals for irrigation and the human, cultural and religious needs.”

She segues into the poetic when speaking of these majestic water bodies: “the strong liquid fingers of the Ganga running through solid rocks”, the river not “simply as a site for a pleasant outing… but an integral and vital theatre of daily life”, the rivers of India as “its temples, its cathedrals”.

And, yet, the ultimate contradiction: where the divine and pristine clash against industrial effluents and clogged estuaries. “Can something be gandagi (polluting) at the same time as being pure?” she asks. “That is a religious discourse of purity. It may look dirty but it’s not impure.”

Bhavya Dore is a Mumbai-based journalist