Last week, the Greek Prime Minister, Kyriakos Mitsotakis was in London, with only one thing on his mind: the return of the so-called “Elgin Marbles” to Athens. 2021 is the two-hundredth anniversary of Greek independence, when the country liberated itself from the yoke of the Ottoman Empire and, for Athens, there would be no better birthday present than the restitution of the lost marbles.

The dispute about their rightful ownership is as old as the modern Greek state. In the early 19th century, the British Ambassador Lord Elgin was granted permission by Athens’ Ottoman rulers to remove half the remaining marble sculptures from a frieze on the Parthenon, the ruined ancient temple, which still adorns the Acropolis, the rocky outcrop overlooking the city.

To break the impasse, Mitsotakis would do well to consider the insights of the ancient rhetoricians

Elgin had the marbles shipped to Britain. The journey, though, proved difficult. They were transported via Malta where, following a shipwreck, they spent a brief sojourn at the bottom of the Mediterranean Sea. The rescue mission was ruinously expensive. Elgin intended to furnish his ancestral Scottish home with the marbles. On second thoughts, though, he cut his losses and sold them to the British Museum.

Public opinion was divided. Lord Byron wrote two poems denouncing Elgin. His supporters, meanwhile, claimed the marbles were saved from further damage at the hands of warring Greeks and Turks, who didn’t appreciate them anyway. The Greeks, understandably, took a dim view of this. Since the 1980s they have waged a sustained PR offensive for the return of the marbles. An impasse, though, remains.

To break it, Mitsotakis would do well to consider the insights of the ancient rhetoricians. Athens, of course, was the birthplace of not only democracy, but rhetoric: the art of persuasion. The philosopher Aristotle, who wrote the original guidebook on the subject, said it was about identifying “the means of persuasion in any given case”. It is the task of modern Athens to work out who it must persuade and what of.

The fresh campaign began with the Government. In Downing Street, after all, lives a man Mitsotakis regards a “true philhellene”. The return of the marbles, the Greek Prime Minister said, after a meeting with Johnson, would be a “coup” for “global Britannia”. Flattery, however, has its limits. The British Government is unwavering in its support for the Museum. Mitsotakis, however, was undeterred. 

Cultural patrimony is the zeitgeist, but Mitsotakis should be wary of making that argument — he should prioritise logic 

In a speech to the Science Museum, he said he wanted to “open a new dialogue” on the issue. The time is right, he believes, because “Museums around the world are increasingly working to share, return, reunite or lend exhibits on an unprecedented scale”. History, in other words, bends towards Athens. The marbles, meanwhile, are “an important link between modern Greeks and their ancestors”. This is an argument about cultural patrimony: the idea certain objects possess inalienable historic, religious, or cultural importance to a group of people. 

Cultural patrimony is, indeed, the zeitgeist. But Mitsotakis should be wary of making that argument for this very reason. The British Museum has made three historic arguments against restitution. First, Athens has nowhere to display the marbles. Second, more people will see them in London. And third, returning them would set a “precedent”. This is the classic “slippery slope” argument.

This has always been the Museum’s position. The issue, though, has become especially sensitive. Cultural institutions, like galleries and theatres, are increasingly vulnerable to culture war style insurgencies. The British Museum must tread carefully. Some of its treasure may have been acquired legally, but a lot of it is colonial loot. Handing back the marbles now could expose it to fresh demands. But rather than allay these fears, Mitsotakis risks provoking them. He is, in fact, arguing there is indeed a slope.

Imagine a Rembrandt or Delacroix painting cut in half and you will get some measure of the Greeks’ distress

Aristotle divided persuasion into three parts: “ethos” meaning character, “pathos” emotion, and “logos”, meaning logic. The British Museum’s arguments are based on logic. They appeal to the head, not to the heart. Athens, by contrast, is making an emotional argument about connecting the past with the present. In public arguments, the Brexit Referendum being one example, “pathos” usually beats “logos”. In this case, however, the British Museum holds all the cards. Only better logic can trump logic. 

Mitsotakis, therefore, must make a logical argument for the restitution of the marbles. He must convince the British Museum this would be an historic exception, not a trend. The Greeks have a good case to do so. Whilst it was once true they had nowhere to display the marbles, that is no longer the case. Since 2009, the collected treasures of the Acropolis have been on display at the Acropolis Museum, which stands directly below the Parthenon. It’s hard to think of a better place to display them.

When Elgin’s men hacked off the marbles, they left half a frieze behind. The body of the goddess Iris now resides in London. Her head is in Athens. This is the masterpiece of the ancient Greek sculptor Phidias. But the story his masterpiece once told is now unfinished; his protagonists mutilated. Imagine a Rembrandt or Delacroix painting cut in half and you will get some measure of the Greeks’ distress. Restored to its former glory, millions would flock to Athens to see it.

These two arguments make Athens’ claim an exception. And there are others. Who, for instance, in modern-day Iraq or Turkey could seriously lay claim to the treasures of Babylonian or Hittite civilisations. There are few treasures so emblematic of a people, and of an entire civilisation, as the Parthenon. The treasures of antiquity are the heirlooms of all humanity: no country has a God-given right to possess or hoard them. That’s true of the Elgin marbles, too. But they would just be better off in Greece.