For all of the “debate” going on in Britain about Brexit (much of which falls woefully short of any reasonable criteria for being considered to be such), little time has been given to examining the real issues with E.U. membership. The problem here may in many cases be wanton partisanship – but there are bigger matters that all sides of a mature debate ought to be able to agree on.

The principle one is that a position based on fact is stronger than one based on assertion (i.e. belief). It is probably necessary (and wise) to set aside epistemological debates on the nature of knowledge – but the difference between a ‘fact’ and an assertion is that the former is supported by provable (i.e. replicable, thus verifiable) evidence whereas the latter is not. In a sense it is ‘belief without proof’ – a definition best applied to religion, but which is much less advisable when it comes to matters of the national future.

I am not suggesting here (even implicitly) that one side has been more deficient than the other in this respect. A mature position would be to accept that a huge amount of what is being discussed lies in the realm of belief – because in the final reckoning it is impossible for any one individual – most of all the “person in the street” – to be in possession of anything like enough information to be able to assemble a factually-robust overview. Thus we are reduced to arguing over beliefs – which are easily overdrawn and is rarely wise.

Therefore, even as a firm Remainer, I ‘ought’ to be able to accept that cases made for remain that are based on assertion rather than fact do not advance the argument, and may even weaken it. Arguments that draw on factually-robust arguments have little need for weaker ones –and recourse to them might suggest that a better case cannot be made.

The same should apply to Leavers. If I were in this camp, I hope I would equally accept that the case for Brexit is best made on a basis of solid fact. I am intending to be as even-handed as possible here, so I hope it is not too partisan to point out that this case was never made. Part of the reason for this was that proof is impossible to obtain when it comes to things that have yet to happen: we can’t know the future, so the best they could do was predict.

The same was true for Remainers arguing the virtue of their case on the basis of the damage Brexit would do: both cases were predicated on more or less accurate extrapolations of the present – and started from the position of confirming their own existing biases. As such, neither offered a good basis for such a momentous decision.

However, Remain did have one key advantage here: the conditions for remaining in the E.U. were known, as they already exist – though this advantage was blown both by the failure of the Remain campaign to use them effectively – and more so because the vast majority of the electorate had so little knowledge against which to measure the veracity of the various arguments with which it was being presented.

In short, nobody knows what the outcome of leaving will be. We might accept the consensus from the majority of ‘experts’ that it will be harmful – but even they are, in the final reckoning, only offering predictions, albeit ones based on more information and insight than the average member of the public can probably muster. The more honest ones will accept that they too are biased.

E.U. membership is such a complex and diverse matter, that even attempting to reduce it to simple certainties is probably unwise. A more mature position is to accept that membership of the EU is a mixed bag: it has its benefits, but given that it is by necessity a compromise between many different national positions, it is imperfect. It therefore has downsides too. A sensible way forward might involve considered weighing of these issues, rather than bunker-mentality absolutism – but binary thinking is the normal way in Britain. Our traditions and systems encourage it – from our parliament down.

It might be more sensible, too, to accept that a view on this depends not only on what you are looking at, but where you are looking from. What appears to one person or country to be a problem may be nothing of the sort to another. The failure to acknowledge this has been a major source of difficulty: with both sides claiming absolute virtue, there was little chance for a mature, considered debate ever to happen.

In particular, the apparent inability of many in Britain to accept the proposal that the EU is a partnership of equals prejudices any views they subsequently take of that enterprise, in a way that does not necessarily happen elsewhere. It is what has always informed the British presumption for special treatment.

Another classic flaw of reasoning is to embody diverse groups as though they are a single individual. Claiming that ‘the British People’ think anything in particular may be convenient, but it cannot be true since 60-plus million people never think as one. The same is true of ‘Europe’ and the E.U. All those claims about the malicious intent of that organisation ignore that fact that it is made up of thousands of individuals, and the idea that they all have a single, united agenda is probably incorrect. It is probably overdrawn even to suggest that its (relatively few) leaders all think the same either. Dealing with that is the whole point of politics.

In the final reckoning, people’s real intentions are known only to them – and attempting to second-guess them, let alone claiming to ‘know’ them, is pointless.

‘Thanks’ to the Facebook page set up to promote my new book, I have heard from a lot of Brexiters recently. I expected this, and did not block comments – though one might think that people who cannot respect the right of others to differ without needing to sabotage it, make a pretty clear statement about themselves at the outset. If they find people like me struggling to accept their views, they could first start by examining their own approach. They fall desperately short of the standards necessary for mature democratic debate, and on that score alone, I find their supposed desire to re-establish Britain as a self-determining democracy hard to accept. Regrettably, the majority of respondents had not taken the trouble to inform themselves that the book is not even really about Brexit before they started shouting. Few were willing to do any more than wield slogans. They do not seem to understand that making a point means more than who can shout loudest, or be the most aggressive.

There were, however, two who were prepared to debate the issue. I applied the basic precepts of critical thinking to their arguments – conceding points whose logic seemed sound, offering alternative interpretations of contentious material as necessary, and supplying references to third-party sources where I believed factual inaccuracies had occurred or unsubtantiable claims had been made.

Only one person did the same in return. He then supplied a link to this article which refers to a now-declassified document FCO 30/1048 apparently showing that Edward Heath deliberately downplayed the implications of Britain’s joining the EEC in 1973 and suggesting that it would be “too late” to reverse by the time public opinion caught up thirty years later.

I have no reason to doubt the existence of this document. But it needs to be evaluated for credibility using the normal ‘CRAVEN’ criteria:

• Corroboration or conflict with other evidence
• Reliability of the report (factual accuracy)
• Ability to see (what it is claims to have witnessed)
• Vested interests of those reporting
• (Relevant) Expertise of those reporting
• Neutrality or bias in their agenda

On this basis, the article falls rapidly apart. Not necessarily because it is lying, but because the source (The Daily Express) is known to be biased towards Leave in the first place – and the language used in the report is clearly not impartial. It ‘leads’ the reader towards certain conclusions, which impartial reporting never does. The more strongly it does this, the more it weakens any claim to objectivity. In this case, analysis of the language used shows it is blatant.

Secondly, there is no attempt to identify, let alone discuss, alternative interpretations – such as the possibility that Heath genuinely believed that it was in the national interest to join the EEC, but that he also knew public opinion would struggle with it when memories of 1939-45 were still much fresher than they are today. It is not as though governments never have hidden agendas – even well-meaning ones…

Finally, the source has pre-judged the article and arrived at a conclusion before it begins: the whole point of the article is not to arrive at the truth, but to convince the reader that a certain interpretation is correct. This is the diametric opposite of how mature debate is conducted.

In case Brexiters reading this conclude that I am simply deploying a subtler than usual form of argument against them – well in a sense, yes I am. (Acknowledging the inevitability of bias is the first step to allowing for it). But I also accept that the other ‘camp’ does the same – it is one reason why I very quickly gave up reading the New European: it is just as partisan as the pro-Brexit press. Even if one argues that some counter-balance was much-needed, the effect has nonetheless been to reinforce bunker mentalities on both sides.

Regrettably (I mean that), those individual Brexiters with whom I engaged soon showed that they could not handle reasoned argument. One resorted to ignoring everything I replied with; he then re-stated his opening gambit that “the EU is corrupt and that is all there is to it”, before disappearing. The second appears to have rejected my response to the ‘evidence’ he supplied, and has also disappeared. This does not lend much credibility to any claim they might have had to having a supportable position; in the end, both resorted to assertion rather than counter my arguments. Why does anyone believe this is adequate? This is not a good basis for the formation of public opinion, let alone national decision-making.

I’m not for a moment claiming to be unbiased on Brexit. But if attempts to engage with people on a mature, intelligent basis routinely fail in this way, then the nation has real problems. As a former teacher, I deeply regret that that profession seems to have failed profoundly in its work of developing more thoughtful, considered individuals within our society.

The whole point about critical thinking is accepting that no one is perfect: we all have biases to set aside before we engage, and even trying to be objective is hard work. But it seems that attempting this – or even acknowledging the need for it – is several steps too far for many people.

My own bias will of course continue to inform the view I hold – but I believe that I have based those views on the firmest evidence I could obtain (including visiting the European Parliament numerous times and talking to MEPs of different parties – even Eurosceptics, to counter claims of presentational bias), and considered allowance for uncertainty.

Unfortunately, the majority of those who might want to change my mind seem to have very little idea of how to go about it. Jeering and sloganising will certainly not work. Quite why they think it will is beyond me, and I can only assume they are unable to do better. It is certainly not the way to restore the democracy they claim to want.

In the end, everyone who failed to attempt reasoned debate on this issue is partly responsible for the tragedy that I think is now the likely outcome. We will probably all be the losers as a result – but infinitely more so if we can’t raise the national debate to better levels than this.