Are you an inner or an outer?” the taxi driver asked me. “I don’t know yet,” I replied.

“How about you?” He was emphatic. “I was an outer,” he said, “but then Boris said he was an outer, so I switched to inner. Can’t stand bloody Johnson. Wrecked the traffic.”

This lesson in advanced political theory left me wondering at the deep emotions that may divide Britons on Brexit. UK Prime Minister David Cameron has freed the topic from the bonds of party and tribe, but in doing so he may have unleashed stranger conflicts. Voters are told to think for themselves, and many find this unprecedented and painful.

Whitehall is clearly in chaos. The environment secretary, Liz Truss, thinks Brexit “risks devastating the livelihoods” of more than 10,000 British sheep farmers. It would “add £90 million to the cost of British lamb exports” and spell disaster. Down the corridor, her fellow Tory George Eustice thinks this “ludicrous”.

It would take “just a few months” to get a free trade deal with the European Union and thereby “secure the Sunday lunch”. How can these two work together? Things seem no better at the business department. Its boss, Sajid Javid, thinks Brexit “too risky”, given the “storm clouds gathering over Europe”. His employment minister, Priti Patel, disagrees. She rubbishes project fear and says “no to an unaccountable federalist European agenda”. Brexit will not cost jobs; it will “empower women”.

Likewise on the good ship Labour. What is it that can really divide Hilary Benn from the no less moderate Gisela Stuart, respectively inner and outer? Or what can divide Margaret Hodge from Kate Hoey? It cannot be the facts, as they all have access to the same ones. Brexit is like the English civil war, when families and friends found themselves split between King and parliament. Other historical divides — as over the reformation, the corn laws or Irish home rule — tended to cohere round religion or self-interest. In the case of Brexit, fragments of the traditional left-right spectrum survive. The left, long opposed to the EU as a capitalist body, now seems to favour it as corporatist one. The right, so often sceptical of big government in opposition, is pro-European in power.

Indeed, both parties are anti in opposition, pro in power. Thatcher campaigned for Europe in the 1970s, and Tony Blair for withdrawal in 1982. People say they want facts, but in truth they want facts that demolish those who disagree with them. A different Brexit spectrum is that of insider versus outsider. Inners tend to have a stake in government as public sector workers, subsidy recipients, entrenched big business and the liberal and academic establishments. Outers embrace mavericks, small enterprises, the unemployed and those fearing immigration. Inners play the security card — project fear — outers play the sovereignty card, project bondage. This might suggest a field day for pedlars of “facts”.

Bodies such as Open Europe, Full Fact, the Institute of Fiscal Studies and even the BBC are frantic to be “objective”.

Hard-wired

The American Jonathan Haidt sees voters as “deeply intuitive creatures whose gut feelings drive out strategic reasoning”. Political parties are no longer custodians of their wallets. They fall back instead on “hard-wired” emotions such as caring for others, family security, religious belief and community identity. How they vote depends on how they feel about themselves. Thus Brexit. It is declining into a sort of primitivism, a debate over what is inherently unknown. Argument is hijacked by hobgoblins.

Outers threaten the voters with torrents of Brussels regulations, waves of immigrants, rampant terrorism and “Cologne-style” mass sex attacks. Inners retort with thousands of jobs lost (Osborne), the NHS in ruins (Jeremy Hunt) and a decade of uncertainty (the Bank of England).

Cameron’s polling advisers keep telling him to plug fear and insecurity. To Haidt, political reason “rides the elephant” of preconception. People say they want facts, but in truth they want facts that support their existing views and demolish those who disagree with them.

Facts are swords and shields, not tools of persuasion. (We of course think none of this applies to us, being thoughtful, open-minded and supremely reasonable.) While reflection, and therefore compromise, might be considered socially preferable, it is by no means dominant. It is riding Haidt’s elephant. What makes the Donald Trump/Ted Cruz contest so compelling in America is its appeal to deep emotions. It delves beneath party and tribe into the personal realm of sexism, jealousy and group hatred. It is political catharsis. Where does this leave our poor referendum campaign?

The answer is closer to Trumpism than we like to admit. The polarisation of the campaign is leading to name-calling, especially among Tories, to such epithets as reckless, racist, dangerous, xenophobic. Inners are attacked as London elitists, comfortable, cosmopolitan and rich. Outers are dismissed as sad, provincial loners with a foreigner problem, hankering after a lost Englishness. Both are, of course, partly true. This leaves ever less space for any “third way”.

Recent writings by such economists as Iain Begg and Roger Bootle confirm the view of an Oxford economist friend of mine, that in 10 years we will have forgotten how we voted. A vote for out will necessitate a new form of in, while a vote for in will lead to such disruptive British behaviour as to be tantamount to out. While this may seem a plausible conclusion, it is no help to the voter. A referendum is a decision. If the facts cancel each other out or are simply unknown, we are forced back on intuition and preconception. How do we feel on the day? What does our vote say about us? Politics can so easily default to some primitive cave in which we cosset our emotions and insecurities.

Such caves can be frightening places for the political psyche. Through them rampage the Trumps and Cruzes, raw with emotion. They offer no shelter to the princes of quiet reason.

— Guardian News & Media Ltd

Simon Jenkins is a journalist and author. His recent books include England’s Hundred Best Views, and Mission Accomplished? The Crisis of International Intervention.