I usually ask the subjects of this column – “is there any link between your academic area and your ethnicity and cultural background?”. “No”, is the occasional curt response.

But Sarah Fine’s work focuses on issues of national identity, discrimination, immigration and minority rights. So, in her case, the connection with her Jewish upbringing is obvious.

Almost everyone reading this column will have parents, grandparents or great grandparents who arrived in this country from elsewhere. Had they not moved country, you, dear reader, would not exist. But would it have been within Britain’s right to deny your ancestors entry? Would it have been acceptable to turn grandfather Sholem away?

To most people, that might seem a silly question. The Brexit vote revealed how strongly many Brits feel about this. Of course, a state should be allowed to set immigration controls, to determine the criteria for entry, to police borders. That’s a fundamental right of every state. Surely?

Dr Fine, who teaches at King’s College London, wants to interrogate this lazy assumption.

On what grounds does the state claim this exclusionary right? Various arguments are offered. One is that the state has the right to defend itself — indeed, providing security is the state’s most basic function. Well, fair enough. That might give it a reason to exclude outsiders who are convicted murderers or ISIS fighters. But grandfather Sholem posed no danger to individuals or to the state.

But the state has always claimed the right to control its borders — doesn’t that, in and of itself, demonstrate its exclusionary right? Not really. Some states in the past (and a few still today) claimed the right to deny exit (think of the USSR) — can we really be confident that the denial of entry is morally superior to the denial of exit?

But we live in a democracy, and surely in a democracy the people get to decide on the rules: and the majority of people don’t want uncontrolled immigration. Well, what is a democracy and who are the people? Presumably, a democracy is a form of government in which autonomous agents like you and me get a say in laws that shape our lives. In the early 20th century, it was impossible to resist the argument that women should have the vote because women were affected by laws passed by parliament. But, in that case, is it so obvious that the voice of grandfather Sholem should be ignored? Whether he was granted entry to Britain was hugely important to him.

Here’s another argument. Should we not regard the state as just like a larger version of a golf club? And don’t we think that it’s fine for a golf club to exclude members? Up to a point. Many golf clubs excluded Jews until around the 1960s, and that doesn’t seem totally OK. In any case, states are not voluntary associations, and the stakes are far higher.

Let’s try a final tack. We need to control our borders to protect our culture, our way of life. Yet even if we grant there’s something in this, we should tread carefully. What is “our” way of life? Is the British way of life Christian? Can it include the way of life of minorities? Is it immutable, or can it evolve? And is protecting a way of life so important that it trumps grandfather Sholem’s desire to move here?

Sarah Fine has distant roots in Poland and Lithuania, but three of her grandparents were born in the north of England. Her parents both grew up in the tight-knit Jewish community in Sunderland.

Most Sunderland Jews departed by the 1970s, and Dr Fine’s parents — the first in the family to attend university — settled in North London. It was a religious home, with a kosher kitchen. She attended the Sinai Jewish Primary School in Kenton.

She found aspects of religion difficult to reconcile with other beliefs and now describes herself as culturally Jewish rather than religious — but she wants to pass on some Jewish learning to her kids. As for her academic work, Sarah Fine says it’s partially inspired by a Torah portion she read during a women’s service when she was a teenager: “And you shall not oppress the stranger, for you know the soul of the strangers, for you were strangers in the land of Egypt”.

@DavidEdmonds100