Tonight on BBC 1 I watched a programme called Rich, Famous and Homeless.

The premise is simple. 5 rich and (allegedly) famous people give up everything and sleep rough in London. They give up credit cards, money, phones, contact with the outside world – the works. Periodically they are filmed on camera, but for the most part they are left to get on with it.

Normally I hate this sort of programme. I detest, for example, the obnoxious Channel 4 show The Secret Millionaire in which self-righteous smug rich people go “undercover” to assess poor people and pick out one lucky pauper to shower with cash. It’s the vindictive Victorian attitude of the “deserving and undeserving poor” all over, and it pushes the message that some are qualified to pass judgement on the lives of others by simple virtue of their wealth.

Rich, Famous and Homeless is not like that. It is excellent television.

Tonight’s episode was dramatic. One celebrity went – in just three days – from a hardcore right-winger (“they’re just bone idle, the homeless, i’d never live like that”) to looking haggard, buying beer instead of food, and confessing how sorry he feels for anyone “who has to live like this”.

In turn, all those celebrities who forced themselves to beg for money described how pathetic and low they felt. One of the participants broke down in tears because “nobody will even look at me. It’s like i’m not even there”.

Another was shocked and distressed after a homeless woman had threatened her, encouraged others to join in, and a knife was pulled in the ensuing confrontation.

But the most powerful scenes came at the end when the celebrities were “buddied-up” with genuine homeless people: a woman abused as a child who has worked as a prostitute and broke down when talking about her mother’s refusal to help her; a man who’d lived on the streets since he was 13 and made ends meet by being a rent boy; another man struggling with heroin addiction, trying to forge a new life so he can see his daughter.

Putting people from the very top end of society with those at the very bottom was powerful stuff. Perhaps the most moving scene was the former hard-line rightist almost breaking down in tears in an abandoned house, saying “I can’t believe anyone lives like this”.

For a brief time last year I worked in a homeless hostel in Oxford. The plight of the people using the hostel hit me hard. I came away with two important realisations:

1. The vast majority of homeless people lack basic social skills: they just don’t understand why it’s important to turn up on time, why it’s important to dress smartly, why it’s important not to shout or be aggressive as soon as things don’t go your way. They simply haven’t learned – or else they’ve forgotten – these things. The result? Normal society is an alien world to them. Job interviews especially become a basic impossibility to navigate. Prioritising rent payments are likewise not comprehended as a basic necessity for getting on with life.

That’s not supposed to be insulting  or patronising to homeless people: it’s simply an observation I made of the vast majority of homeless people I came into contact with – and it explains in part why so many of them are and remain homeless.

2. Most homeless people are alcoholics, heroin addicts, crack addicts or all three. This is just a fact. Do most of them become drug addicts and then lose their homes, or do they lose their homes and then become addicts? I don’t know and I don’t care. Why? Because homelessness is horrible. As Rich, Famous and Homeless has effectively portrayed, being homeless is dangerous, exhausting, mentally and emotionally devastating, debilitating and demeaning. Just because somebody takes illegal drugs, that does not justify or make irrelevant the horrific circumstances they live in. It does not provide us with a license to ignore.

What makes Rich, Famous and Homeless such a powerful and important piece of television is that it helps to make these realisations accessible to many people who may be very dismissive of the plight of the homeless. From my experience, many people rationalise homelessness by telling themselves that homeless people “deserve it” or are “choosing” to be homeless or that they are “on the take and doing really well out of it”.

Indeed, this is hardly surprising. The Fabian Society has recently been publicising its findings that people prefer to live in a world which they think is fair – even if all empirical evidence is to the contrary: people rationalise and justify gross inequality in society by reasoning that it must be fair or deserved inequality – and that way they don’t need to worry about it.

The same thing happens with homelessness. People don’t want to believe that the homeless are such because they have been unlucky, or abused, or neglected, or have simply fallen through the cracks of society – and have then been forgotten and abandoned by the rest of us.

What Rich, Famous and Homeless does is show that such easy rationalisations of homelessness cannot be sustained. Most homeless people do not “deserve” to be homeless – and even if they do “deserve” to be homeless, so what? They’re still human, and still suffering – and that’s not something we can justifiably ignore.

TRANSPARENCY EDIT EXPLANATION: Removed references to “ordinary people” as it sounded smug and didn’t convey what I was trying to say properly.