The human brain, like every other brain on this planet, evolved to do certain things – to survive and reproduce.

Sitting within us are a lot of basic motivational systems. We are motivated to be alert to threats and to take defensive action. That’s what gives us the basis to be anxious, aggressive, and depressed. But we are also motivated to form caring attachments to kin and friends, to be compassionate to those we know and even in certain contexts those we don’t. Tragically though, the history of human slavery, wars and atrocities shows that leaders and politicians often stimulate our threat-focused, aggressive and nastier traits while suppressing our compassionate sides.

So, what have our evolved minds got to do with Brexit? Well first they limit our capacity to understand the issues in front of us. There is simply not enough information or processing power available for us to assess all of the likely outcomes from Brexit or no Brexit and to make anything like a rational decision as a result.

Second, when people make a decision like this, a lot of it is based on their own, pre-built self-identity. So it is not just a case of “I made a decision to Leave or Remain and now, on the basis of new information, I can change my mind,” because it is more: “I am fused with my decision, my decision is part of my identity, the person I see myself as, and the group I believe I belong to – ‘I am’ a Leaver versus a Remainer or visa versa.” The argument is tribal. It’s my group identity against the other, or my party against the other.

So why is it difficult to change our minds in the light of new information? To change my mind I have to accept a change of identify and a shift in group. That might bring me into conflict with those around me. I must also accept that I made an error, and we know that that can be difficult for us if it makes us feel a bit inadequate and at fault. Sometimes, to avoid those feelings, we may try to justify bad decisions rather than change, and the more we try to justify the decision, our inner reasoning increases our conviction rather than reduces it. The more you present climate change deniers with evidence the more they believe that it’s fake.

Brexit deal vote: Opposing groups of protesters gather by parliament Show all 20 1 /20 Brexit deal vote: Opposing groups of protesters gather by parliament Brexit deal vote: Opposing groups of protesters gather by parliament Brexit supporters outside parliament PA Brexit deal vote: Opposing groups of protesters gather by parliament An anti-Brexit protester adjusts her pro-EU wig AFP/Getty Brexit deal vote: Opposing groups of protesters gather by parliament A message to Jeremy Corbyn in support of a people’s vote Getty Brexit deal vote: Opposing groups of protesters gather by parliament A mock Titanic captained by Theresa May heads towards an iceberg in a stunt by campaigning group Avaaz AP Brexit deal vote: Opposing groups of protesters gather by parliament Anti-Brexit protesters outside parliament PA Brexit deal vote: Opposing groups of protesters gather by parliament Protesters of opposing sides are in close contact outside of parliament PA Brexit deal vote: Opposing groups of protesters gather by parliament Paintings of Theresa May and Jeremy Corbyn Getty Brexit deal vote: Opposing groups of protesters gather by parliament Former Ukip leader Nigel Farage speaks to the media at the protests outside parliament Reuters Brexit deal vote: Opposing groups of protesters gather by parliament A pro-Brexit protester in Parliament Square Getty Brexit deal vote: Opposing groups of protesters gather by parliament Opposing protesters share the space outside parliament Getty Brexit deal vote: Opposing groups of protesters gather by parliament An anti-Brexit protester holds EU balloons outside parliament Reuters Brexit deal vote: Opposing groups of protesters gather by parliament Anti-Brexit protesters stand on Westminster Bridge PA Brexit deal vote: Opposing groups of protesters gather by parliament Former Ukip leader Nigel Farage speaks to the media at the protests outside parliament Reuters Brexit deal vote: Opposing groups of protesters gather by parliament Anti-Brexit protesters demonstrate outside the Houses of Parliament EPA Brexit deal vote: Opposing groups of protesters gather by parliament A pro-Brexit protester sets up outside parliament Reuters Brexit deal vote: Opposing groups of protesters gather by parliament An Avaaz campaigner holds a People’s Vote life float Reuters Brexit deal vote: Opposing groups of protesters gather by parliament A demonstrator holds a sign advocating a no-deal Brexit outside parliament AFP/Getty Brexit deal vote: Opposing groups of protesters gather by parliament An anti-Brexit protester waves an EU flag on Westminster Bridge PA Brexit deal vote: Opposing groups of protesters gather by parliament Protesters of opposing sides demonstrate outside parliament AFP/Getty Brexit deal vote: Opposing groups of protesters gather by parliament Protesters of opposing sides stand near parliament Reuters

And of course our some of our politicians do not help us. Since the politician first appeared on planet Earth they have been first and foremost manipulators of minds; persuaders, enticers, warners, encouragers, promisers, defenders; operating on our threat and potential reward systems of the brain. In order to do that they must tap into the archetypal and emotional within us. After the Second World War, we were a traumatised country with a deep desire to end the conflict and division and create a fairer more caring social order. Compassion was our basic motivation and it was easy to stimulate because of our environment.

Within 15 years of the end of the war we had built a National Health Service, education system, and a range of public services that were the envy of the world. We had no money. Taxation was high. However as the trauma of the war receded and complacency of the achievements set in, politicians began to stimulate different motivational systems within us, ones which also had an ancient past and passion, ones of competitive self-interest. It became about the individual. These too are rooted in human nature – they are not inevitable feelings but they are there to be manipulated.

The rest, as they say, is history. We are now living in societies that are highly competitive where we are becoming more anxious and depressed and with increasing disparities of wealth that are unsustainable. In our hearts we all know that if we continue the way we are our children will grow up to live in an even more fragmented and tribally violent world. The tragedy is that even while knowing this, we do nothing. There are no good and bad actors here: simply conductors of the human mind playing outdated archetypal stories.

And so we arrive back at Brexit – manipulation on both sides, emotive calls, tribalism, competition, a search for easy answers to complex questions. And at this moment in time: stubbornness and doublethink.

When a politician argues that a second referendum is a betrayal of democracy we know we’re dealing with a serious problem because there’s no way in the world that they actually believe that. Imagine going to buy a house and you are enthusiastic. Clearly you are free to pull out on the basis of new information. Clearly people should always be allowed to make decisions on the basis of new information; that is the bases of democracy not a betrayal of it.

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Our problem is that the world has become so complicated that we’re struggling to find the information we need to make sensible decisions and to counterbalance the manipulative tactics of some politicians.

Brexit is a symptom of a far more serious problem than we recognise. Given the way the world is fragmenting under the drive of competitive pressure, we have not worked out how best to govern ourselves to create the world we want for our grandchildren to grow up in.

In our hearts we know we need a radical change but are struggling to work out exactly what and how. Movements like Compassion in Politics are addressing the serious challenges ahead, highlighting that compassion is not some simple form of kindness or of being nice, but is one of our most courageous and difficult of all our motives. It transforms how our minds, brains, bodies and social networks work and I hope it will soon transform our politics.