The Scotland in which I and, no doubt, many of you grew up was not a particularly diverse or enlightened place. It was – in a few unhappy ways still is – a starkly homogenous society that didn’t take kindly to change or difference.

The main division, certainly in central and western parts, was religion, the male instinct for aggressive tribalism finding its home in social segregation, lurid, borrowed hatreds and the Old Firm. We drank too much, beat our wives, were emotionally stunted. We died young.

If we avoided the flashpoints of other communities, it wasn’t down to moral maturity. Two examples spring to mind: race and gay rights. When I first travelled to London for work in my early 20s, I found myself crammed into a tube carriage directly behind a black guy.

I had never been so close to a black person before and, like a country bumpkin, I was mesmerised by his skin tone and hair. When I moved to London at the ripe old age of 33, I worked and became friends with a sizeable number of gay people who lived openly and contentedly. To my knowledge, I had met one openly homosexual man in my previous three decades, a statistical impossibility that tells you something about how wary Scots had been of the possible consequences of coming out.

Living in the London melting pot is soul-enriching. You become colour blind but also a connoisseur of the beauty in the different races around you, a devourer of exotic foods from far-flung corners of the earth, at home amid the mellifluous babble of languages. The startling, the experimental, the louchely flamboyant become commonplace. Unless you have the unfortunate distemper of a Nigel Farage, you learn to enjoy – to need, to revel in – diversity.

The advance of liberalism has been a great civilising force and has massively increased the general happiness of our species. Acceptance of others as they are; tolerance of those who make personal choices we don’t agree with or even understand; the wisdom to acknowledge one’s own opinions are often just that rather than indisputable fact, the willingness to discuss and debate without attempting to shut down opposing points of view – these are the essence of the liberal.

As the philosopher John Stuart Mill’s “harm principle” puts it, “the only purpose for which power can be rightfully exercised over any member of a civilised community, against his will, is to prevent harm to others”. Bertrand Russell added another dimension: “The essence of the liberal outlook lies not in what opinions are held but in how they are held: instead of being held dogmatically, they are held tentatively, and with a consciousness that new evidence may at any moment lead to their abandonment.” Liberalism demands a posture that is open, curious and adaptable. We live in an era of accelerated liberal progress. Gay rights have made an exponential leap forward and gender equality has improved in important areas.

Every political party bar Ukip would describe itself as socially liberal and would be unlikely to attempt to roll back any of the key changes made.

But this fleetness of foot has also created problems that should give the true liberal pause for thought. There is undeniable unease among a sizeable chunk of the population about the pace of change. Immigration has transformed some communities and undermined traditional models of identity and belonging. Globalisation and technology have upended the workplace.

Gay marriage and abortion pose profound dilemmas of conscience for those whose faith carries a conservative tint. Elderly people can find themselves overwhelmed by the digital revolution or alienated by debates around issues like gender fluidity. None of which is to say any of these advances are wrong or should not have been pursued, and that there aren’t more summits to conquer. But we have adopted Mark Zuckerberg’s Facebook philosophy of “move fast and break things”. Not everyone has kept up, and not everyone has wanted to, or wanted what existed to be broken. And the losers are not always treated kindly, even – or especially – by liberals.

The backlash against “liberal overreach” has given us Brexit, Donald Trump, Mr Farage and a host of unpleasant extremist movements across the West. The tendency has been to condemn those who backed Brexit, Mr Trump or Ukip as bigots, to look on them as under-evolved, lacking empathy or generosity of spirit. One might fairly argue that, while not all Brexiters are bigots, most bigots are Brexiters and that there is a wider set of irredentist values that defines the cohort.

That’s not the whole story. I don’t share Jacob Rees-Mogg’s politics. I disagree with his opinions on abortion and gay marriage and it may turn out he was unwise to air them, given his political ambitions. But as someone who was raised a Catholic and who understands the tenets of that faith and the devotion that some have to them, I don’t regard his views as extraordinary. I think he and the Church are wrong but I also accept he thinks I’m wrong. I get no sense he’s a bigot, the definition of which is someone who is intolerant towards those holding different opinions. In fact, Mr Rees-Mogg seems entirely tolerant of alternative views.

The same is true of Tim Farron, the former Liberal Democrat leader who got into trouble during the General Election campaign over his views on homosexuality. In his resignation speech, he said he was “a liberal to my finger tips … passionate about defending the rights and liberties of people who believe different things to me”. He may have made a mess of his campaign but it’s pretty miserable to deny his point.

The Christian parents on the Isle of Wight who withdrew their children from a school that allowed a boy to wear a dress and teaches pupils about “gender inappropriate pronouns” are a harder case. They may look, to those with different values, slightly unhinged and they have shown intolerance to others. But a liberal can look at issues like abortion and transgender not just as a matter for science but also as ethical questions, which by their nature are unresolved and possibly unresolvable.

The delegitimisation of opposing views, as opposed to healthy dispute and even acceptance of unbridgeable difference, is, at heart, illiberal. We should be better than that.