John Rhys-Davies: 'We've created a subclass that only knows human misery'

The Big Issue: Are fantasy films simple escapism or opportunities to explore real-world issues in an engaging way?

John Rhys-Davies: I like science fiction rather than fantasy. I do not normally warm to fantasy in the sense of magic and elves and goblins – they don’t really do it for me. I’ve always liked the hard science fiction that takes an interesting line and tries to work out the consequences of that. It’s marvellous good fortune to have had so many opportunities in film and television.

Surely actors make their own luck?

Don’t we all? Once we get over the schoolboy notion that our genius is such that the world will beat down the grass just to get to us and receive our wisdom, I think we do realise we have to have a go at every opportunity.

The really successful politicians of our time – Putin, Salmond – are people who actually do put their countries first

I’m still waiting for the world to work out I’m not a genius.

Because you’re only a boy. Now you know my theory about human development, do you? When the adolescent growth spurt starts all the bones of the body grow, including the skull. The brain has to physically adapt itself to this new bigger box. That doesn’t happen overnight. In fact, it doesn’t end until somewhere between the ages of 24 and 26. The last two areas that become fully functional are the prefrontal cortex, which is the region that determines things like judgement, and an area around the amygdala, which has to do with primary feelings: fear, rage, anger, despair. We should be caring for our children as children a lot longer than we do. It’s not a case of pushing them out the door at 18 to get on with things, yet we allow them to drink, marry, vote and drive at a time they’re not fully capable of sound judgements.

In Scotland the voting age was lowered to 16. But you would raise it to 26?

Absolutely. It’s part of the bread and circuses attitude that particularly the Labour party has had over the last 20 years – reduce the voting age, keep the pubs open. We have destroyed the intelligent, rational working class and created a subclass that has only really known human misery. Is that too controversial for you?

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In the past you have called Britain “pretty morally vacuous”. Are there discussions that as a society we’re just not having?

That’s exactly it. We have such intellectually inadequate leaders that you just wince. Cameron, Brown and Blair must be the least qualified men to govern a country that we’ve had in 200 years. When you look at a politician, the first question you should ask is, does this man love his people? Will this man put his country first? That’s not the only quality we want, but the really successful politicians of our time – Putin, Salmond – are people who actually do put their countries first.

Between the fall of Rome and 1300 there was no appreciable increase in income per capita for most people in Europe. Between 1300 and 1700 it doubles. Then the second industrial revolution brought such a conflux of discoveries [resulting in a 12-fold increase of income per capita between 1870 and 1970]. This concept grew: “I’ve done better than my father, my children are going to do better than me, because that’s the way things are.” That binds up our future – so that the fact that we’ve not had enough babies for 50 years is a disaster unless we have more migration, because it is only through growth of population that we’re going to expand our standards of living.

The phenomenon between 1870 and 1970 is a freak. Revolutionary technologies are not going to be as transformative as the innovations during that period, and we are now heading to an era where a growth in income per capita is going to regress to that very low norm. All our assumptions about needing to have more people in the country in order to grow and maintain our standard of living are wrong. We should manage our natural population decline in such a way that preserves a higher standard of living by restricting new migrants.

Benedict Cumberbatch was among nearly 300 arts figures who have publicly backed remaining in the EU. Why should people listen to what actors have to say?

They shouldn’t necessarily. Every actor has a right to his opinion; they [Cumberbatch & co] are, of course, completely wrong. Their generation has been brought up without a sense of national identity. They have lived protected in the world. The world is at a more dangerous time now than it’s been since I was doing my Cambridge entrance exams in Cuba week. We have a desperately inadequate American president and he has allowed the wolves to get strong, and now the wolves are gathering.