The origin of citizens, or the race into which they were born, is of no concern to me. I have only one criterion by which to distinguish them - virtue. For me, any good foreigner is a Greek and any bad Greek is worse than a barbarian.
Alexander the Great's words, spoken to a gathering of peoples from the empire he created in the fourth century BC, are a fitting introduction to Thessaloniki, the third largest Greek city in the world after Athens (and Melbourne). They are prominently displayed at its international airport.
Founded in 315 BC and called after his sister, historically it is one of the world's great multicultural cities. It has been ruled successively since then by Greeks, Romans, Byzantines, Ottomans (when it was known as Salonika) and, since 1912, by the independent Greek state, which captured it in the first Balkan war. After that it was occupied by the French and British in the first World War (commemorated in the Cork ballad about the Munster Fusiliers and the wives they left behind them) and brutally by Nazi Germany in the second.
Because of its strategic location and great natural harbour, Thessaloniki has always drawn in peoples from the surrounding regions and countries and provided them an opportunity to mix and prosper - when they were not fighting one another or besieging the city. It has been a fulcrum of imperial prosperity or decline, most notably in the late 19th century, when Serbs, Macedonians, Bulgarians competed to fill the vacuum left by the disintegrating Ottoman empire, in co-operation with the great imperial powers of Europe, which realised full well its strategic importance as a gateway to the Middle East.
As a result the city has been exposed in the last 80 years to periods of the tragic separation of peoples as well as their mixing. Following Greece's disastrous Anatolian war of 1920-22 it was agreed that 1.3 million Orthodox Greeks would be expelled from Turkey to Greece, while 800,000 Muslims would go the other way. In the process, multicultural Salonika, the Ottoman Trieste, became the much more Hellenised Thessaloniki in the mid-war period.
Its celebrated Jewish population of 60,000 survived that transition, only to fall foul of Nazism in 1943-44 - 46,000 men, women and children were transported to the Auschwitz gas chambers and killed. Their ancestors had come to Salonika in the 1490s after being expelled from Spain and Portugal. They were welcomed by the city's new Ottoman rulers and given a privileged position in its trading and commercial life, becoming probably the most sophisticated Jewish population in the world for 400 years. Only a few thousand of them survive in the city today.
In the last 10 years the collapse of the Soviet Union and the wars of the Yugoslav succession have also washed over Thessaloniki. Although Greece has not been directly involved it is highly aware of the destabilising potential of these changes and their associated "ethnic cleansings". The city's population has mushroomed to over 1.2 million, as hundreds of thousands of refugees and migrants from Albania, Bulgaria, the former Yugoslav republic of Macedonia and other states have joined Greeks returning from the USSR and a great migration from the surrounding countryside in search of work.
The city is therefore recovering some of its historical multicultural character - and is in a strong position to benefit from the opening up of the region to trade and European integration. This point was made forcefully last weekend by the President of the European Commission, Mr Romano Prodi, in Thessaloniki to mark the 20th anniversary of Greece's membership of the EEC/EU.
He said it "has a crucial role in the reconstruction of the Balkans", where its entrepreneurial spirit can contribute to a "winwin" process of change and development. Several EU agencies to do with training and reconstruction are based in the city.
Mr Prodi went on to praise Greece's "moderation, wisdom and sense of collective interest" through the last 10 years, and especially during the recent Kosovo and Macedonian crises. He took the opportunity to repeat his vision that the Balkan states must become real actors in European politics. Within the perspective of their eventual full EU membership, there is much that can be done to create a "virtual membership" in the meantime, through peacemaking, economic development, growing regional trade and investment.
Thessaloniki is a Mediterranean port, and that sea is "finding its way back to the centre of history", as Mr Prodi put it. "It has always been the crossroads between Europe, Africa and Asia. As Asia develops and as North Africa and the EU seek to develop closer ties, that crossroads is becoming more important".
This is an ambitious vision indeed, which Mr Prodi linked not only to the EU enlargement process but to quasi-constitutional debate on the EU's future inaugurated by the Treaty of Nice, on which a referendum is to be held here this summer.
The basic questions concern whether the new political structures being created will be sufficient to accomplish the tasks set out for them. The Greek Prime Minister, Mr Costas Simitis, addressed the issues involved in an impressive speech surveying Greece's own experience of membership at the ceremony in Thessaloniki's new concert hall. He called for a Europe-wide debate on "what we want to achieve with integration".
His basic approach is that "we want a strong Europe because we want a strong Greece - Greece is bound to Europe and Greek progress depends on Europe." The last 20 years have shown they have a common fate and "knocked down the myth of a kinless nation". He spoke of the need to go beyond traditional nationalism. His policy of engagement with Turkey has transformed their relations, creating a partnership approach to EU enlargement (and allowing the Greek defence budget to be cut to enable membership of the eurozone).
Mr Simitis supports a deeper, federal-type EU; otherwise such a large structure will risk "creeping crisis and dismantlement". It needs a constitutional text to settle its basic law. It also needs sufficient resources to enable the candidate states develop and catch up, mechanisms to ensure social cohesion and justice, and guarantees that newcomers will have equal political treatment and access by the common institutions.
Such proposals to pool identities as well as sovereignties contain many echoes of Thessaloniki's history. Alexander's inclusive vision of citizenship remains astonishingly topical.
