BACK in the days when reality TV could still be seen as something of an anthropological experiment, Channel Four broke with the norm by showing the residents of the Celebrity Big Brother house footage of the outside world.

The occasion was the inauguration of Barack Obama as the 44th President of the United States and there were two reactions in particular the cameras were keen to linger on. Rapper Coolio and singer Latoya Jackson did not disappoint, both breaking down in tears at the sight of a black man being welcomed into the highest office in their land. It was visceral and moving and articulated in just a few seconds what it means to know that people like you matter, that their experiences count and that their talents will be recognised.

When Sharon White was last week announced as the new chairman of John Lewis the reaction was the same, with staff at the department store chain reportedly weeping when they received the news. Given that such roles are typically reserved for the white, privately educated males that few of the business’s employees have anything in common with, it is easy to see why.

A state-educated black woman who made her own way to Cambridge University 30 years after her Windrush-generation parents came to Britain, Ms White is everything an expected business leader is not. At a company where 16 per cent of staff are from a black, Asian or ethnic minority background, and where the preponderance of men in senior roles has led to an average gender pay gap of 13%, she is in many ways the role model par excellence.

As the current chief executive of communications regulator Ofcom, economics graduate Ms White has also held high office everywhere from the Treasury to the World Bank to the Department of Justice. Conspiracy theorists take note: her appointment at John Lewis was made on the strength of her stellar CV rather than any boxes she will allow the company to tick. Nevertheless, it is what her hire says to those who feel marginalised by society that may end up mattering most, with a senior figure at John Lewis acknowledging that “this is a really, really big deal for some people; role models are so important”.

Anyone who doubts that is probably a white, middle class male, who, from the moment he has was able to look, has seen his own image reflected back at him wherever he has gone. Whether he wants to run a business or lead a country he has the confidence to aim high because nothing has ever told him it cannot be done. Role models like Ms White show the bright, capable and talented women and ethnic minorities too often put off from also aiming high that they can fulfil their potential too.

Not that they should expect it to come easy, with the quest for diversity too often quashed by organisations that would benefit from supporting it. The journalist and author Caitlin Moran has spoken many times about trying to secure a commission for her sitcom Raised by Wolves only to be told by one television executive “we’ve already got a female comedy this year”. How depressing to think that female representation could be reduced to filling a box that is waiting to be ticked or - worse still - that ticking it could be seen as an end in itself.

Nor is Caitlin Moran’s experience remarkable, with a single, token woman regularly to be found on street names, at boardroom tables or on television panels. At least we get that one, though. When it comes to black people and ethnic minorities, public acknowledgements that their experiences count, that their histories matter and that their futures can be different remain woefully few and far between.

Like John Lewis, the Bank of England has it in its gift to help incrementally change that. A campaign led by lawyer Zehra Zaidi and backed by the Treasury is calling on the establishment to feature a person of colour on its new £50 note, with Crimean War nurse Mary Seacole, Second World War radio operator Noor Inayat Khan, abolitionist Olaudah Equiano and suffragette Sophie Duleep Singh among the names put forward.

They are all worthy contenders and in selecting one the bank would not only be publicly acknowledging the part ethnic minorities have played in our past, but would be sending a message about the value placed on their current contributions too. The writer Afua Hirsch has said that the refusal to consider the merits of the campaign would be “a powerful reminder of how little our institutions seem to care”. Choosing a person of colour would be a powerful statement of how much they do.

Back in 2009, after recovering from the overwhelming emotion of watching Obama’s inauguration, a visibly moved Coolio felt inspired to, in his words, “talk to the world”. Turning to the cameras he said to whoever was watching: “Don’t anyone tell you what you can or cannot do in your life. Dream big. Dream of the stars.” It was a fitting reminder that none of us should ever underestimate the power of representation.