On a recent day, a spindly couch and other heaped up items — a busted end table, a CD rack — appeared in front of my apartment building in San Francisco. My first though was that it must have been left by some departing tenant too lazy to have the rejects hauled away.

Then I saw a pair of legs, still as sticks, protruding from under the couch. I looked closer at what suddenly, absurdly, struck me as a human chrysalis paused in mid-emergence.

The legs wore dark loose pants and black shoes (one on, one off). It was a man, I figured. As I stared, a woman casually walked her dog inches by the tableau, ignoring it. So did her dog.

I went upstairs and, in a rare instance for me, finally decided to call 911. The operator asked, “Dead or alive? Breathing?” I said I didn’t know, noting that the torso was kind of under a couch.

Within minutes, sirens sounded. A fire truck arrived. From my window angle, I saw two people get out and stoop by the legs. Eventually, the rest of the body emerged. Yes, it was a man and, thank God, he was alive.

I couldn’t hear what anyone said, but soon the fire truck and crew left. The emerged man, pulling a blanket of sorts over his shoulders, moved unsteadily up the block of my pretty treelined street. And, to my eyes, he disappeared.

The incident was a microcosm, I well knew, of homelessness.

Having interviewed a formerly homeless man and people close to him for nearly a decade (usually in the multi-faceted, hopeful and sometimes seemingly hopeless Tenderloin neighborhood little more than a mile away from mine), I should not have been surprised the legs lay literally so close to home.

I know that far more dramatic interactions than what happened in front of my home play out hourly across the Bay Area, the country and the world. As someone who never lacked a safe (however uncomfortable) place to sleep, I learned much from my interviews.

Here in San Francisco, I learned a person can have a full-time job and still be homeless. I learned some homeless people prefer to live in a sidewalk tent rather than sleep, or try to, in a shelter bed near countless other people with countless other issues.

I’ve learned some shelters kick out their “guests” as early as 6 a.m. Where are they supposed to go? Perhaps beneath a discarded couch.

I’ve learned there is much that housed people like me can do, apart from writing a book. According to the formerly crack-addicted and homeless Del Seymour, whom I interviewed the most and who started a remarkable free jobs training program, Code Tenderloin, for disenfranchised people such as he had been, those responses can start modestly. The most basic thing we can do is to consider saying hello.

What most unsheltered people need more than anything, he says, is dignity. They are fellow human beings. Maybe offer enough money to buy food or offer a pair of clean socks. Next time you see the person, say hello again. Make a connection, if that seems possible and comfortable. Let someone know you’re willing to talk. Maybe, eventually, offer a shower, a cell phone or a job.

When in the Tenderloin, which of those offers have I made? Few. Some self-conscious hellos, dollars and sandwiches. More damning, I never called 911, despite not knowing if someone crumpled on the sidewalk was alive. Yes, I have watched for evidence of a chest rising and falling to make sure they are breathing. It seems the least I can do. Sometimes, though, I don’t even do that.

At what point did I start thinking that in my neighborhood, but not in the Tenderloin, the sight of only part of a person warrants active intervention?

Homelessness is soul-robbing to us all.

Author Alison Owings is a former Mill Valley resident. Her latest book is titled “Mayor of the Tenderloin: Del Seymour’s Journey from Living on the Streets to Fighting Homelessness in San Francisco.”