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I've lived in the United Kingdom for 7 years now. Knowing this site is frequented by Americans (of which I am one) but not really knowing how much of a "thing" Brexit is in America at the moment, I am not entirely sure how much detail to go into when explaining it.
But basically, the United Kingdom (England, Wales, Scotland and Northern Ireland) has been a member of the European Union since 1973. The European Union is a political and economic union of 28 nations in Europe. This includes such components as shared currency (though there are exceptions; The United Kingdom never switched to euros as a currency) and freedom of movement, which basically means any EU citizen can move to any nation within the EU at any given time, and working as a bloc when generating many trade deals. The EU also has certain standards that countries must adhere to. Essentially, the United Kingdom has been entrenched in this relationship for decades.
In 2016, the citizens of the United Kingdom voted to leave the European Union. But the UK currently remains a member due largely to the huge legal and economic complications in severing the relationship.
To say Britain is divided over this would be a great understatement. Ministers in parliament have had their lives (and their children) threatened. One was even shot and killed by a man yelling about Brexit a few years ago.
As a psychologist interested in motivated reasoning and people's (in)ability to recognize their own biases, I have been drawn to that aspect of the process of Brexit. There is so much evidence that people are quite poor at recognizing their own biases, though they do recognize bias in others. That is to say, people don't deny that various psychological biases occur so much as they deny that they themselves are susceptible to those biases.
This is largely because our biases develop in many ways outside our conscious awareness. We aren't aware it has happened, and as such, when we introspect (self-reflect), we don't see this bias in play. This is the case with many parts of culture; we don't realize really how it impacts us because it is just business as usual while we are learning and experiencing the culture growing up. For me, this was brought home hard when I moved to England, both in how culture had impacted people native to the country and, to a much lesser extent, how growing up American had impacted me.
I see this failure to recognize bias in basically everything to do with Brexit. It is as if every single political party here (large or small) fails to understand what the other parties are arguing pretty much all the time.
To take but a few examples:
1) The conservatives keep saying that the other parties don't want a new election. The other parties keep saying quite clearly they do, but the conservatives must rule out a no-deal Brexit happening amidst these elections first. (The Prime Minister wants this so he can perhaps get a majority he doesn't have at the moment, but he needs the approval of Parliament.)
2) The opposing parties keep saying they represent the people (they are elected), but many of them (like the Liberal Democrats) don't seem to see the contradiction between that and not leaving the European Union, which is what the people voted for.
3) The conservatives keep claiming that leaving the EU—deal or not—is what the people voted for. But it isn't, really. No one voted to leave the European Union without a deal. They voted for all the promises that were made about what will happen when the UK leaves the EU. Many of which were lies spread by the Prime Minister himself. The other parties seem to recognize this.
Another interesting part of this is how people react to the usage of false information in the Brexit vote. It's quite clear that Cambridge Analytica spread false information through social media. Boris Johnson himself appeared in adverts that claimed—very falsely—that the UK sends £350 million a week to the EU. But of course Brexit voters don't think this played a role in their votes. Opponents of Brexit do. This is very consistent with studies showing that people tend to think that social factors (media, etc) do not impact them, if at all, certainly as much as they do other people. This has been dubbed the 'alone in a crowd of sheep effect'.
Of course at the level of the politicians there are clear motives to keep spreading false info and misunderstanding each other. The parties want power. But, it is more than that. I think the people themselves are so blind to their own biases that they don't see their own inconsistencies and this makes it very difficult to hear the actual arguments and points of the opposing parties.
At the voter level, it is much more clearly about not recognising their own biases. People just will not admit to themselves that they may have been influenced by false information.
I'm singling out Brexit voters here, but to be clear, this same thing would apply to their opponents (Remain voters) if the situations were reversed. Had Brexit not passed and there been false info spread to help that vote, then Remain voters would be insisting that the false information played no role in their votes.
You see the same sort of bias blindness and motivated reasoning in the U.S. at the moment with Trump's impeachment and the Ukraine transcript. People who want Trump out seem to be reading an entirely different transcript than the people who don't.
