If the citizens of Harappa and Mohenjo-daro had composed the Vedas, the Ganga would be less dirty. This thought is prompted by twin concerns of the Bharatiya Janata Party government. The first is the Clean India campaign, along with its special focus on the Ganga. The second involves an article of faith of all Hindu nationalists: that the Vedic people originated in India. Or, in other words that the oldest civilisation discovered in India that of the Indus Valley, was itself a Vedic society.The idea of the two being identical, encapsulated in the phrase Indus-Sarasvati civilisation, is misguided on a number of counts. I will mention just one. The Vedic people were big on horses and chariots. Their gods had fancy rides, and the control of chariots and horses was among the coveted powers of Indra, the Rg Veda’s top god. The continuing symbolic importance of the chariot in India long after it ceased being an effective war machine is demonstrated by the 13th century AD construction of Konarak’s Sun Temple in the form of a gigantic chariot with elaborately carved spoked wheels.Horse-drawn chariots, like all complicated artefacts, leave remains in the ground when they fall apart. Yokes and collars that held animals together or bits of wheel and axle are buried in the ground waiting for modern archaeologists to dig them out. In places where languages closely related to Vedic Sanskrit were spoken, plenty of evidence has emerged of horse drawn chariots. Within Indus Valley sites, right-leaning archaeologists have sought such remains as assiduously as American troops searched for Saddam Hussein’s weapons of mass destruction, and with as little success. There isn’t a hint of a chariot till well past the civilisation’s peak. Till a point, in fact, when one might reasonably expect early Vedic people to have brought their knowledge of chariots to the Indus Valley from the northwest, given the conventional dating of both Harappan sites and the composition of the Vedas.If the absence of horse-drawn chariots is an important pointer, I consider the lack of adequate sanitary provisions in Indian cities after the collapse of Harappa and Mohenjo-daro equally significant. Consider that the one feature that set these cities apart from all other ancient sites was their elaborate sewage system. If they were part of a civilisation that continues unbroken to this day, how did we completely forget this defining quality? How did we, over hundreds of years, construct massive townships, all the way down to contemporary Gurgaon, without any proper thought to sanitation?Time will tell whether Narendra Modi’s Clean India campaign makes a greater impact than previous sanitation drives and whether his effort to clean the Ganga improve upon Rajiv Gandhi’s Ganga Action Plan launched in 1986 without warning the public to mind the gap between promise and execution. Referring to past failures, Shashi Tharoor, who has been invited by the Prime Minister to be part of the mission, wrote , “The fundamental problem lies in our people's ingrained behaviour patterns ‒ and mindsets are the hardest things to change...we are a nation full of people who live in immaculate homes where we bathe twice a day, but think nothing of littering public spaces, spitting on walls, dumping garbage in the open and urinating and defecating in public, because those spaces are not "ours." It is this individualistic mindset and lack of civic consciousness that makes our country a land of private cleanliness and public squalor.”As early as the 7th century AD, Tsuan-tsang (contemporary spelling Xuanzang) observed something similar. Indians, he stated, “are very particular in their personal cleanliness”, but about Indian towns he wrote, "… the streets and lanes are tortuous, and the roads winding. The thoroughfares are dirty." We aren’t the only nation with squalor and dirt visible everywhere, but filth defines us in a way it doesn’t, say, Cambodia, or Burma, or Burundi, which are poorer and possess fewer resources.I believe the root cause of India’s identification with grime can be expressed in one word: caste. The Rig Veda speaks about a four-fold caste hierarchy, which, some time after the pastoral Vedic people had transitioned into an agrarian society, but some time before Gautam Buddha visited Varanasi, had become a rigid five-level structure, in which certain acts were considered ritually defiling, to be undertaken only by those considered impure by birth.Indus Valley cities show no evidence of caste: they are neat grids that include all citizens. Citywide public works such as complex drainage systems are predicated on such inclusiveness. Within a caste-based society, there simply isn’t enough commonality between Brahmins and ati-shudras for the former to plan anything that takes into account the needs and desires of the latter. Shashi Tharoor was wrong to lay the blame for our lack of civic consciousness at the door of individualism. The blame lies with our caste consciousness. Gandhi understood this, and his preoccupation with the cleaning of toilets, which so many commentators have found puzzling, was a way of tackling caste in ways government programmes wouldn’t manage. If Narendra Modi comprehends it, he is doing a good job of keeping the thought to himself.