Kieron O’Hara is an associate professor and senior research fellow in electronics and computer science at the University of Southampton. He has also written extensively on conservatism and the Conservative Party.

Everyone got very excited about the news from the Royal Family – Prince Harry is engaged to someone I have never heard of called Meghan Markle, an actress, model and humanitarian. Even Noam Chomsky, whose politics are as unconvincing as the linguistics upon which his reputation was built, and Giles Fraser, who believes he has the freehold on the moral high ground, are enthusiastic. The Prince has chosen to marry a woman whose ethnic heritage is different from his own, and so there has been a little frisson that the Royal Family will be just a little bit (but not much) more representative of the British nation as a whole.

All well and good. Certainly, one wishes them happiness. What interested me about the flurry of comment was the importance of their being representative. In particular: the common acceptance of the fallacy that representative democracy requires a government that itself is representative of the citizenry.

This fallacy is more often applied, with somewhat more vehemence, to Parliament. The source of most if not all of our political woes, goes this story, is that our MPs are pale, male and stale. They do not look like the vibrant, diverse communities they represent. This is, of course, true, and has always been so. The question is why that is such a bad thing.

There are two currents of ideas at work here. Firstly, there is the distinction between a representative and a delegate. In Burke’s famous letter to his constituents in Bristol (who voted him out, it has to be said), he emphasised the importance of the MP’s job as representing the interests of his or her voters, whether or not they voted for or against, in the creation and scrutiny of legislation, and in holding the executive to account. The MP’s experience was unique to him or her, and would be at the service of the constituency.

But the MP was no mere delegate – he or she was not in Parliament to follow orders. “His unbiased opinion, his mature judgement, his enlightened conscience, he ought not to sacrifice to you; to any man, or to any set of men living. These he does not derive from your pleasure; no, nor from the Law and the Constitution. They are a trust from Providence, for the abuse of which he is deeply answerable. Your Representative owes you, not his industry only, but his judgement; and he betrays, instead of serving you, if he sacrifices it to your opinion.”

Second, there is the distinction between Parliament representing the nation, and its being representative of it (in its makeup). The thesis that Parliament should be representative is part of a more general idea which emerged in the eighteenth century that politics should be the implementation of the will of the people, or what was called the general will. It is the basis of all populist arguments that politics pits an elite against “the people”, and that the main purpose of political action is to cast aside the elite and its hegemony to let the general will prevail. If Parliament has been captured by the elite, then it should be bypassed. Jean-Jacques Rousseau, Jeremy Corbyn and Nigel Farage have very little in common, but they all believe that.

There are many problems with this argument, which superior intellects from James Madison to Bernard Crick have explained. Its particular political difficulty is that it creates its own slippery slope. Once a reasonable person has muttered that Parliament is too unrepresentative, he or she has accepted the principle that it is there to be representative, and has thereby created a space for those who despise representative democracy. The demagogues who believe that they express the wills of millions far prefer direct democracy; dictators love referendums and hate free elections.

The evidence for the slippery slope is clear and obvious. Fifty or sixty years ago, Parliament was divided almost equally between Old Etonian toffs and horny-handed trade unionists from heavy industry. There was no gender balance. There was no ethnic balance. Half of Parliament went to Balliol, and half failed their 11+ (I caricature, but only a little). Nowadays, Parliament is far more representative of the nation as a whole, in all demographic respects. This is, we are asked to believe, wholly a good thing. Yet its reputation has never been lower. Respect for our institutions of authority has declined steadily and dramatically as they have become more representative. Correlation is not causation, but becoming more representative (more inclusive, in the jargon) has hardly helped their standing.

The reason is equally clear and obvious: each time those who champion representative democracy give ground to the demagogues, they further undermine their own position. Down the slippery slope they go.

The false dichotomy of “the elite” versus “the people” is given credence by each retreat, each concession. Parliament has become a punchbag, the root cause of every problem. “The people”, on the other hand, are permanently sinned against while never sinning. The financial crisis, for example, was caused by the elite, nothing to do with record levels of household debt.

When we try to make Parliament representative in this demographic way, we turn a complex cultural interaction between parties, individual MPs and the large and heterogeneous communities they represent into a crude numbers game. It certainly solves no problems.

Looking for an echo of ourselves in the Royal Family is an even bigger mistake. Even though there is no-one paler, maler or staler than me, the royals are a million miles from being my representatives. I have literally nothing in common with these people. I did not vote for them, I do not ask them to represent me, and (I suppose) if I had to vote for a monarch, I might vote for someone else. But that’s not what monarchs are, so I’m rather glad that the Queen is the Queen. ‘Monarch’ is a somewhat underspecified job description, but I subscribe to the broad consensus that, whatever the job is, the Queen has done it rather well.

Similarly, what I want from my MP is the expertise and experience to understand where I am coming from, in all my different identities, as a son of an immigrant, an academic with a career in education and science, a privacy advocate, someone who cares about the environment, someone who values social stability, of an urban rather than a rural background, and so on. And I accept that she also needs to understand people who have completely different points of view, and help forge compromises and modi operandi between those various interests. That my MP is a former businesswoman, and in that respect moves in different circles from mine, matters much less than her ability to understand my perspective, and to defend what I value when it comes under threat.

We the people are heterogeneous, not homogenous. That heterogeneity cannot be transplanted into Parliament. Parliament is not, should not be and probably cannot be a faithful reflection of the flux that confuses us in daily life. Rather, it should be part of the process of rendering that flux acceptable and understandable to the citizens of Britain. If it has done this job rather badly recently (and I believe it has), it is because too many Parliamentarians, commentators and voters do not comprehend this fundamental principle.