The gym on the second floor of Diana’s fancy apartment complex on San Francisco’s 5th street was empty. Like the outdoor terrace with barbecue grills and fire places, the gym is included in the rent. Most people who live here have their apartments paid for by their company, or can afford to drop six grand a month on a one bedroom place. Most of them also have a job, so I had the fitness room all to myself at 10am on a Thursday morning.

Running on one of five treadmills, I had a great view onto 5th Street, which was busy with traffic. A couple in their late forties or early fifties shuffled around the corner, each of them pushing a shopping cart piled high with their belongings. The man, with thinning hair and a long beard, looked like he’d worked a construction job for decades. The woman must have been a petite blonde in her younger years.

They stopped by the curb just opposite of my window, where two parked cars had left a gap. With the two shopping carts behind her, the woman dropped her pants, sat down on the sidewalk as if it was a toilet seat. Then did her business, in full view of the traffic passing by and the building I was in.

As much as I wanted to, I couldn’t look away. Her partner, in the meantime, seemed unfazed and was smoking a cigarette. Then handed her some toilet paper. The blonde got up, and both pushed their carts down the street. While I was still contemplating what I had just witnessed, she came back and draped a piece of cardboard over the turd, blocking it from view.

The scene left me baffled. There I was, in my fancy gym enjoying an air conditioned work-out in an apartment complex that leaves nothing to be wished for, while just a couple of meters away someone doesn’t seem to have access to a flushing toilet. Or has taken up a lifestyle in which going for a poo using the curb as a seat is the most normal thing in the world. Somehow, this seemed emblematic of a city that is one of the richest in the US, yet has a staggering amount of people living on it’s streets. And few people give a shit, so to speak.

In some parts of the city, the homeless dominate the streetscape. Walking through Tenderloin at 4pm in the afternoon, you will see a long line of people of all ages, queuing around the corner of Ellis and Taylor in line for the shelter. Continuing south towards Market Street, dozens more are sleeping in the shade, begging for money, staring silently in a stupor or shouting curses at imaginary pursuers or real passersby. Many of them seem to have mental health issues which, in other countries, would probably have them living in a hospital or care facility, rather than on the streets.

No matter how many times I travel to the US and how much I love this city, I find it hard to get used to this sight. I can’t think of another place, apart from Delhi, where I’ve seen as many homeless people left largely to their own device. How is it that, in one of the most developed countries in the world, people who once contributed to society are left without access to healthcare or a place to sleep? Why has nobody figured out a solution, in an area awash with money and talent? The Valley stands for inventing the future by solving complex problems: turning pee into drinking water, developing self driving cars, growing burgers in a petri dish. In comparison, homelessness on it's doorsteps seems like a trivial problem to solve. San Francisco has such a brilliant mind - sometimes I wish it would also have more of a heart.