NEW DELHI — As we weave through early-morning Delhi traffic on his motorbike, Ravi Gulati gets into a riff about status symbols in India, how from Armani jeans to Audis they are almost all Western, and how his car, a cheap and practical Maruti van that seats eight but won’t win any beauty contests, is a source of derision every time he pulls up at a five-star hotel for some lavish weeklong wedding (although he tries to avoid these occasions) that has cost more than is imaginable to a poor Indian.

Gulati, a mild-mannered man in his early 40s, was on the fast track to fortune, an M.B.A. student at a top school, the Indian Institute of Management, when a course he took on Indian agriculture taught by a professor who had walked, like Gandhi, from village to village got him thinking that his country had lost the plot and that an elite gobbling up new condos for $3 million or more had grown blind to the fact that trickle-down was a downright myth. A booming India of rising middle-class fortunes had parted company with a bigger one still mired in distress, and without any real debate India, like much of the world, had embraced Margaret Thatcher’s “There is no such thing as society” as a prevailing idea.

Nowhere is inequality — what President Obama this month called “the defining challenge of our time” — more in your face than in India. Brand-filled shopping malls spread. So do shanties. A rich man builds a 27-story house for his family in a nation of 1.2 billion people where more than a quarter of them — or roughly the U.S. population — lives on less than two bucks a day. Outdoor defecation is still widespread. Yet when Gulati, a social activist engaged in teaching poor Delhi kids through a nongovernmental organization called Manzil, tries to interest his peers in the subject of inequality, he tends to find the conversation goes nowhere, drowned by talk of some juicy real-estate deal for farmland south of Delhi, the latest Bollywood hot item numbers, or the Silicon-Valley success story of yet another Indian immigrant.

“We are giving aid to America. It’s crazy!” Gulati tells me. “We are sending our finest minds all over the world to help enrich the countries they adopt, but not India, which desperately needs them.” He points to a shanty where “children lie in the mud while their parents look for work.”