I deal with the economics of Brexit every day, but it took this to remind me how deeply personal it is

While politicians must understand the mechanics of leaving the EU, they should also try harder to take notice of the incredibly emotional response it has stirred

As the director of an economic think tank based just metres from parliament, I am aware that I can become overly immersed in the statistics and theories that underpin my analysis of Brexit.

The same thing was on my mind when I stepped out of the offices of the National Institute of Economic and Social Research last Friday afternoon to catch the last rays of the sun as they caught the Baroque roof of St John's church on Smith Square.

As I entered the square, I saw a march of schoolchildren walking from right to left, scuttling to perhaps their last lesson of the week. They were looking both over their shoulders for the traffic but also immediately to their left directly at one of their number who was standing on the corner of street. A young man was standing in the square, singing “Jerusalem”, the words made famous to my generation through a TV documentary about a public school in 1980 with all those connotations of early Thatcherism involving aspiration and patriotism.

The words and his voice wavered in the cold and suggested some nerves in the full glare of his schoolmates, but he was powerful and clear. Why was this young boy standing on the corner singing? Was he busking or had he lost a bet? It became clearer as I approached the edge of the square.

The young man was a corner facing the direction of a small band of protestors standing in the opposite. It is a corner that has been occupied by the European Commission since 2010, having been vacated by Conservative Central Office in 2004.

The protestors were in a variety of fancy dress, familiar to anyone who has been, for example, to the West Stand at Headingley. They were protesting, as is their right, about the European Union and asking the bureaucrats to leave the country. But some time before I arrived, a stray comment from one or more of the protestors had offended the young man.

At one point he drew breath and shouted back: “Just because I look foreign it does not mean I do not belong here.” His anger was not projected through violence or aggression but by the simple articulation of a song long associated with English nationalism. He sang it bravely. His school-friends, carrying a wide variety of hues, smiled and encouraged him.

There is no one I know who does not carry multiple identities. For many, attempting to list all of them is often a complex and tiring affair. But this young man was predominantly proud of belonging to this country. His emotional bond was strong enough to cause his eyes to well up in the course of singing his song. Any sacrifices his parents may have made to bring up a British child seemed to be have yielded a positive benefit for this country. Because here was a young man not only proud of his but also prepared to proudly proclaim it to those opposed to his presence in Britain. Though he may have misheard a comment from the protestors (and I was prepared to give them the benefit of the doubt), his solo response was quite remarkable.

It was a timely reminder for me that Brexit is ultimately a personal and emotional issue for many people. While politicians must understand the economics of Brexit – and economists produce impartial and robust assessments – it is essential that whatever happens on 31 January and in the weeks, months and years that follow, that there must be a healing process to ensure that everyone can stand alongside each other in national solidarity.

Jagjit Chadha is director of the National Institute of Economic and Social Research